'4./ U. S. DEPARTMENT OF AGRICULTURE. DIVISION OF ENTOMOLOGY— BULLETIN NO 4,. L. O. HOWARD, Entomologist. THE CODLING MOTH PREPARED UNDER THE DIRECTION OF THE ENTOMOLOGIST C. B. SI^TPSOjST, Special Field Agent. WASHINGTON: GOVERNMENT PRINTING OFFICE. 19 03. Bui 41. New Series. Div.of Entomology, U.S. Depr.of Agriculture. Tin- dotted j/arttiiTUte Austral Zorues i oftAe tirvat Phtins indicate the extent oftiir hamid divisions „ft7iese Zones, known res,,ee tivcly astne ARjefftXajuan Cnro/inzttn and Ans tj-orifariari FaumtbS TlU Tmdotted. /jar-ts oTtfu- Zones are. knoM-n, as the Transition t/pper Sonoran and Zower So? December, 1897. LIFE ZONES OF THE UNITED STATES BY C.HART MERRIAM U. S. DEPARTMENT OF AGRICULTURE. DIVISION OF ENTOMOLOGY— BULLETIN NO. 41. L. O. HOWARD, Entomologist. THE CODLING MOTH PREPARED UNDER THE DIRECTION OF THE ENTOMOLOGIST O. B. SIMPSON, Special Field Agent. WASHINGTON : GOVERNMENT PRINTING OFFICE. 1903. n/Vlsmx OF ENTOMOLOGY I.. I >. I l«»w lbd, Entomologist. C. L. M \ki \n, in charge of i vperimental field work. V. II. Chittenden, mcharg\ of breeding experiments. A. I). Hopkins, in charge of forest insect investigations. Frank Benton, in charge of apiculture. \\ l>. Ih nter, '// charge of cotton-boll weevil investigations. I >. W. Coqdillett, Th. Peboandb, Nathan Hanks, Assistant Entomologists. E. A. Schwarz, I".. S. «■. Titus, Investigators. Miss II. A. Kelly, Special agent in silk investigations. I; 8. Clifton, 1". C. Pratt, A.ugust Bdsck, Otto Heidemann, A. N. Caudell, .1. KOTINSKY, II. ns 35 Description of the cocoon 36 5 6 Life history ( Sontinued. • Page. The larval Btage < lontinued. I Miration of the Btagee in the coc-.un : ( >7 [nfluence of temperature upon the duration of the stage 38 Effect of the insect upon the fruil 39 The pupa 39 Emergence of the moth .°>9 The adull insect 40 1 low to distinguish the sexes 10 Habits of the moth 41 Duration of life of the moth 1 < fenerations of the insect 41 Sen-, u ia I history 50 Emergence of the moth 50 Relation between the emergence of the moth and the blooming period... 51 Hibernation 54 Evidences of a third generation 55 ( 'oiiclusion 56 Natural conditions which tend to decrease numbers 57 Natural enemies. 57 I inert el irate enemies 59 How to com hat the insect 00 Preventive measures 00 Setting the trees 62 Pruning 68 Irrigation (54 Boil or cover crops 04 Orchard in bearing 04 Preparing fruil for the market 65 Preventive measures in old orchards. 07 Treatment of old orchards OS Remedial measures 69 Measures of little or no value 69 Measures of value 72 Measures used against the larva 72 Materials for Bpraying 80 Cost of spraying 83 Time and frequency of application of spray 85 I low the poison kills the insect 86 The banding system 88 Expense of banding 91 When 1-auds may be used 92 Practical tests 92 Resume* and conclusion *'0 Bibliography of the more important contributions to the literature of the cod- ling moth 97 ILLUSTRATIONS. PLATES. Paere Pla te I. Life zones of the United States Frontispiece. II. Fig. 1. — Apple leaf inhabited by codling-moth larva. Fig. 2. — Apples damaged by caterpillar 16 III. Eggs of the codling moth 16 IV. Fig. 1. — Entrance holes of larvae of second generation. Figs. 2 and 3. — Views in orchard of Hon. Edgar- Wilson 32 V. Fig. 1. — Codling moth larva, enlarged about three times. Fig. 2. — The "worm hole" or exit hole of the apple worm (enlarged). Fig. 3.— A wormy apple, showing the familiar mass of brown par- ticles thrown out at the blossom end by the young larva (from Slingerlaud ) 32 VI. Fig. 1. — Larvae, pupa-, and moths on rough bark. Fig. 2. — Infested apples being rmr'ied 48 VII. Fig. 1. — Codling moth enlarged four times. Fig. 2. — Codling moths enlarged twice. Fig. 3. — Codling moths, natural size 48 VIII. Stubs of branches trom an old orchard near Elkton, Md., showing work of codling-moth larvae and wo; ulpeckers 64 IX. View in orchard of Hon. Fremont Wood, near Boise, Idaho 64 X. Fig. 1. — Band on which the remains of 330 cocoons were counted. Fig. 2. — Pupa in cocoon on underside of a loose piece of bark. Fig. 3. — Larva and pupae in cracks in bark from which rough bark has been removed 80 XI. Gasoline power spraying machines 80 XII. Spraying outfits in use 80 XIII. Clean and wormy apples from tree Xo. 2, Wilson orchard 96 XIV. Clean and wormy apples from tree No. 4, Wilson orchard 96 XV. Clean and wormy apples from tree No. 6, Wilson orchard 96 XVI. Preparing apples for market, orchard of Hon. Fremont Wood, Boise, Idaho 96 TEXT FIGURES. Fig. 1. Anarsia lineatella 21 2. Plodia interpunctella 22 3. Larverna herellera 22 4. Nephopteryx rubrizonella 23 5. Daily band record made by II. !' the records made by II. E. Burke, at Boise, [daho, in L902, to det ermine the maximum of the second generation 52 in. Record by EL C. Close, Utah Agricultural College 53 1 7. Spraying outfit for treating tall trees ; 75 18. Large apple tree properly banded for the codlingmoth (original)... 89 l ( .i. Apple tree banded, showing bands both above and below a hole in the tree 89 THE CODLING MOTH ( ( hrpocapsa pomonella Linn.) INTRODUCTION. Every person is acquainted with "wormy apples/' and many have seen the caterpillars in the fruit, while- few know the history of the worm-like creature which causes the injury, or whence it comes or whither it goes. If apple insects were classified in the order of the degree and extent to which the}' cause monetary loss, the codling moth would rank first, since it causes more injury than all other insect enemies of this fruit combined. It is the most serious drawback with which the apple grower has to contend, as from one -fourth to one-half of the apple crop of the United States is injured every year. The control of this pest, how- ever, is not difficult when compared with that of many other insects, and hosts of apple growers are each year saving practically all of their crop from its ravages. In the literature of the subject, one finds that Cato makes the first mention of this insect, and since that time almost every entomologist has studied it and written about it. By the writings of LeBaron, Walsh, Riley. Cook, Goff, Forbes, Howard, Slingerland, and many others, information about its life history and remedial measures lias been disseminated, which have facilitated its control in the eastern part of the United States. It was found that in the western United States the conditions were different from those in the East and that the recommendations which brought success in the East did not give satisfactory results in the West, and the necessity arose of making a close study of the western conditions. Among those who have written on the insect in the West are Messrs. Washburn, Koebele, Card, Aldrich, Gillette. Cordley, and Cooley. The two principal accounts of this insect are those by Dr. L. O. Howard in 1888 and Prof. M. V. Slingerland in 1898. Both of these writings give a summary of what was known of the insect at those dates, with many original observations and suggestions for its control. 10 Slingerland's bulletin is especially comprehensive, partly because of the late date <>t' its publication, and partly because a complete bibliog- raphyand valuable historical notesare given. The excellent observa- tions and photographs arc important features of this publication, which has been of t ho greatest assistance t<> the writer of this bulletin. The writer is under obligation to many for the aid given in this work. Hon. Edgar Wilson, Hon. Fremont Wood, and Mr. W. F. Cash rendered assistance in carrying oul the practical tests; Mr. Alex. McPherson, the State horticultural inspector, made observations and gave aid in many ways; Mi*. S. M. Blandford, of the United States Weather Bureau, at Boise, kindly furnished the temperature data used; Mr. II. F. Burke, of the Department of Agriculture, assisted in the work in L902, and did much valuable and accurate work upon the life history of the insect; Prof. C. P. Gillette and Mr. I). W. Coquillett kindly gave the writer access to their notes. Many fruit growers in Idaho have rendered especially valuable aid in keeping records. Pro- fessor Slingerland granted permission to use many of his figures, and his bibliography, with his notes, is used as a foundation for that por- tion of this bulletin. Prof. J. M. Aldrich, Prof. A. P.. Cordley, and Prof. C. V. Piper have at all times given aid, counsel, and advice, and granted permission to use their unpublished data. The estimates of injuries inflicted by the codling moth given in this bulletin are based principally upon observations made upon check trees in Bpraying experiments. SYSTEMATIC POSITION. The codling moth belongs to the order Lepidoptera, or scale-bear- ing insects, and has been assigned to the family Tortricida 1 . The description of the genus Oarpocapsa Treitschke, as given by Meyrick, i- ;t- follow-: Antennas in $ simple. Palpi moderate, curved, ascending. Thorax smooth. Fbrewings with termen Blightly sinuate. Hindwings in $ with longitudinal groove below cell, including a hair pencil; 3 and t connate or stalked. ."> nearly parallel to 1, «> and 7 closely approximated toward l>ase. A small hut rather widely distributed genua. * * * The species pomonetta is distinguished from the other species by having the margin of the ocellus (or black spol on the wing) of a coppery metallic color. (See 1*1. VII.) The description of poinonetta in given by Meyrick :»vs follows: li r.i mill. Porewings dark fuscous, finely irrorated with whitish, with darker basal patch sometimes darker; a large dark coppery brown terminal patch hardly reaching costa, anterior edge more blackish, ocellos within this edged with bright coppery metallic. Hindwings fuscous, darker terminally. 11 NAMES OF THE INSECT, POPULAR NAMES. The name " codling moth" is the one most generally used by the American fruit growers. The first name given to this insect was *'pear eater." on account of its feeding in pears. Later writers called it the "apple and pear worm or moth,'' "fruit worm," "fruit moth," and many others names. The name "apple worm" is often used, especially by the English. Wilkes, an English author, first used the name in 1747, which name was taken from a kind of apple tree. Slingerland says that the word "codling" is doubtless a corruption of the old English word "querd- lying," which means any immature or half -grown apple. Some hor- ticulturists and entomologists and others use the names "coddling" or "codlin." As a result of extended research Slingerland discards these names and gives the name "codling" decided preference. SCIENTIFIC NAMES. In 1758 Linnaeus gave this insect the specific name of pomonella and the discription is as follows: "Alis nebulosis postice macula rubra aurea." Schiffermulier. 1770, named it "pomonana." Fab ricius. 1793. gave it the name " pomona." By reason of the eighteen years priority the name "pomonella" stands. Linnaeus gave this insect the generic name of Tmea. Later it was known as PyraHs^ Tortrix, Semasia, and Erminea. Still later it was given the name Carpocapsa, which was in use for about three-quarters of a century. In 1897 Walsingham concluded that the name Carpocaj. >sa must fall and be replaced by Cydia. This view was adopted by Fernald in Dyar's list of North American Lepidoptera; but Cockerell strongly doubted this conclusion. After a very exhaustive study of the sub- ject Mr. Busck concludes that the old name Carpocapsa is the proper name and must be restored, and his conclusions are accepted in this publication. VARIETIES OF CODLING MOTH. Stand inger described a variety of the codling moth which was bred from either apple or walnut in which the coppery spots in the ocellus were more broken and gave it the name of jmtaminana. It has evidently been thought for many years that there was a variety of the codling moth in the far west. Matthew Cooke said in 1883: "From investigation it is probable that there are more than one species of codling moth infesting the fruit of this State [California], but 1 am not prepared to report at the present writing." In 1900 the writer found one buff-colored moth which, except for color, was like the common codling moth, on the trunk of a tree at 12 Boise, Idaho. During 1901 four well-preserved specimens and eight badly worn specimens were secured. In L902 six of these buff-colored moths wore bred among L82 normal moths. In material collected in Idaho in the fall of l'.xijj, from which about 30 moths emerged the following spring, five were of this variety. Mr. A. F. Hitt, of Weiser, Idaho, and Mr. Alex. MePherson. tell the writer that they have noticed these buff-colored moth-. Mr. Hitt, in L896, bred seven of these among 50 normal moths. The writer submitted the moths to Mr. August Busck, of the Tinted State- Department of Agriculture, for determination, and in the Proceedings of the Entomological Society of Washington he describes them as follows: These Bpecimens were submitted to the writer for determination, and I have care- fully examinedl hem structurally in comparison with the common form of Cydia{^) pomoneUa Linne. I do not think there can be any doubt about their being this Species; the "nil parts, the venation, the secondary male sexual character of the hind wing, and the external sexual organs of both sexes are identically as found in the common dark form of the codling moth. The general pattern of ornamentation is also the same, but the coloration is so strikingly different that the variety deserves a special name, the more so as no intermediate forms seem to occur. I propose that it l>e known as Oydia (M pomoneUa Linne, var. simpsonii. Instead of the dark fuscous color of the common form, the variety is light buff, With slightly darker buff transverse striation. In the common form the forewings are finely irrorated with white, each scale being slightly white tipped; in simpsonii the BCales are not white tipped. The terminal patch, which in the common form is dark coppery brown, nearly black, and with dark violaceous metallic streaks, is in simps' ni ii light fawn brown with pure golden metallic streaks. The extreme apical edge before the cilia is in the common form black, in the variety reddish brown, and the cilia in simpsonii are light golden ocherous instead of the dark fuscous of the common form. The head, palpi, body, legs, and the tuft of hairs on the hind wings of the male are correspondingly light-buff colored in the variety instead of dark foSCOOS, as in the common form. Besides Mr. Simpson's specimens, in which both sexes are equally represented, there is in the United States National Museum a single female, labeled "Cook, Cali- fornia. July 30, 1883." Type: No. 6803, United States National Museum. The writer has never observed any gradations between this variety and the common form, [t is most probable that this variety is dis- tinctly western, as there are no records of its having been bred in the East. No attempt was made to secure the earlier stages of tin 1 insect, and. a> far as observations were made, its life history IS similar to that of the normal form of the codling moth, as tin 4 larvae from which this variety was bred were taken with the larva' of the normal form under bands on apple trees. One might theorize On what conditions in the West have given rise to this new variety, but to state with any degree "Tin- generic name Cydia used by Mr. Busck before bis investigations, which resulted in the restoration of the old name ( hrpooapsa. 13 of certainty exactly what has brought about this change is impossible from the data at hand. GEOGRAPHICAL DISTRIBUTION. The original home of the codling moth is not definitely known, but is supposed to be southeastern Europe, the home of the apple. It has followed the distribution of the apple closely until it is now present, with but few exceptions, in all countries where apples are grown. It ha- spread over Europe, and is present as far as the apple region extends in Siberia. It was noted in Australia about 1855. Tasmania about 1861. New Zealand in 1871:, South Africa about 1885, and Zeller received it from Brazil in 1891. Mr. C. L. Marlatt reports that he did not observe this insect in either Japan or China in his extended travels in those regions. Mr. George W. Compere also states that he has never observed it in China. Prof. A. B. Cordley states that this insect has reached China. Evi- dently some correspondent of his has reported it as present in that country. As apples are being continually shipped to both Japan and China, it is but a question of a few years when it will either be intro- duced or become injurious in the orchards of those countries. Extended researches of many investigators have failed to give date or definite information as to the time and manner of introduction of the codling moth into America. For a long time injury to the apple by this insect wa^ thought to be the work of the plum curculio; and it was not till 1819 that the codling moth was reared from wormy apples by Burrell. It was evidently quite well distributed in the eastern United States before its work was identified, as there are but few records of its spread. In 181:0 it was a serious pest in New Eng- land and central New York. About 1860 it invaded Iowa. For many years it has been a serious pest in Canada. Mr. Alexander Craw stated in 1893 that the insect was first introduced into California by means of some fruit brought from the East to Sacramento for exhibi- tion purposes in 1872. No measures were taken to destroy the insects in this fruit, and two years later its presence in abundance was noted. Later it was rapidly distributed over the State, aided by the system of returning boxes. Dr. C. V. Riley mentions in 1876 that this insect was then present in Utah, where it had evidently been introduced a year or two previously. From these points of infestation the codling moth spread over the Western States. Prof. J. M. Aldrich states that it has been known in the Clearwater Valley in Idaho since 1887. Mr. I. L. Tiner. of Boise, states that in 1887 he found the first indication of this insect at Boise. Idaho. Mr. Thomas Davis, of Boise, states that it was intro- duced into his orchard at about the same time. 14 RELATION OF DISTRIBUTION TO LIFE ZONES. Although the codling modi muv be brought into a section ol country, it may not be able to obtain a foothold on account of the adverse cli- mate. In other regions it is never very injurious, or it may be quite injurious one year and almost absent the next; hut in warmer regions it reaches the maximum of destructiveness. In order to study these conditions the writer has used the life zone- of Dr. C. Hart Merriam (PI. I). Upon consulting this map one finds that there are seven different /ones in the United State-. In the eastern portion they, in a general way. extend east and west, while in the western part they are broken into irregular areas by the mountain ranges. There are many important subdivisions of these zones, depending principally upon the amount of moisture and the milder and more temperate climate near the seacoasts. BOREAL ZONK. 'The principal apple-growing regions of this zone are in Nova Scotia. northern Maine, northern Michigan, and western Oregon. Except for the Pacific coast strip, only the more hardy varieties of apple- are grown in this zone. There is ;i great lack of definite data in regard to the exact amount of injury the insect causes in this zone. As near as the writer can learn, the injury is never so great as it is in the next warmer zone. According to Cordley, the insect is present in small numbers in the Pacific coast strip and is doing but a comparatively small amount of injury. TRANSITION ZONE. The transition zone includes the greatest apple-producing regions of the United States, the A lleghenian area comprising the zone in the eastern mountain State-, including the larger part of the apple-grow- ing regions of New York, Pennsylvania, and Michigan. Although the injury, which varies with the seasons, is greater in the transition than in the boreal zone and less than in the austral, no record of definite percentages has been found during the present study. In the arid area of the transition zone the loss is less than in the Alleghenian area. Various estimates of from .~) to 25 per cent so per cent at Fort Collin-. Colo., varying with the degree of infestation in the Locality. 15 Cooley reports an injury of 95 per cent in small home orchards in Helena. Mont. There are many regions in this faunal area in which the insect does about 25 per cent damage, and for some reason, prob- ably climatic, the injury is reduced to almost nothing for several years, after which the numbers of the insect gradually increase. Professor Aldrich records that in 1899 an early snowfall and low tem- perature at Moscow. Idaho, killed a great many of the larvae. There are many other localities in the Pacific Northwest where the codling moth either has not been introduced or has not thrived, and in which the injury is nominal. In many regions where the transition zone is pierced by valley- of the upper Sonoran zone the orchards near the canyons sutler much greater injury than those more remote therefrom. Professor Piper has noted several cases in which this was true, and in one the damage was 75 per cent or over. THE PACIFIC COAST TRANSITIONAL AREA. This area includes those portions of Oregon and Washington be- tween tin- Coast Mountains and the Cascade Range, parts of northern California, and most of the coast region of the State from near Cape Mendocino southward to the Santa Barbara Mountains. In Oregon varying percentages of injury have been reported, ranging from a nom- inal los< to 75 per cent. In the Hood River Valley in some cases it is greater than this, with an average, perhaps, of about 2b to 90 percent. UPPER AUSTRAL ZONE. The upper austral zone is divided into two areas by reason of the greater humidity of the eastern portion. THE CAROLINIAN FACNAL AREA. This area includes the great apple regions of the Central States and many smaller portions of the Eastern States. Many entomologists have reported injury in these areas a- ranging from 3U or 50 percent to practically 100 per cent. UPPER SONORAN FAUNAL AREA. This area includes that portion of the upper austral zone west of the one hundredth meridian. From many countings and estimates from various sources we tind that in badly infested districts the injury varies from 80 to 95 per cent under normal conditions, and it is very common to find the loss reach 100 per cent. LOWER AUSTRAE ZONE. In this zone there are only a few localities where apples are grown on a commercial scale Under normal conditions in badly infested L6 localities the Loss is almost total. Garcia records, from check tree- in spraying experiments, that the loss varied from 67 to 99 percent. There are manj localities in this /.one in itoth east and \se-t where apple can be grown, l>nt on account of the injuries due to the codling moth other crops are groiR d instead. IMMUNE REGIONS. In iiianx regions of the Far West one often hears the fruit growers -m\ that on account of the peculiar climatic conditions of that region apples are free from injury and the codling moth can not exist. Among these climatic condition- quoted are dense fogs, mountain breezes, and comparatively high altitude-. Seven or eight years ago it was thought that the Hood River Valley was immune from the insect; the same was thought of the Pajora Valley in California; but later development- have shown that immunity was due to the fact that the insect had not been introduced into those localities. It has also been .-aid that there was no codling moth near the coast in Oregon, but Professor Cordley finds that it i- present in some localities and believes that the former immunity was due to isolation. In many restricted areas in the Pacific Northwest more or Less isolated the codling moth i- either absent or present in such small numbers that it ha- not been observed. From past experience and examination of these Localities it is evident that the insect in its gen- eral spread has not yet reached them. It is a question whether or not the insect will be injurious in these localities, but it is certain that it can be present. The writer has no hesitancy in concluding that there is no region in the Pacific Northwest in which apples are grown in which the codling moth can not exist. Many causes of immunity by isolation in river valleys have been noted. The most marked case is at Mr. I. B. Perrine's orchard at Blue Lake. Idaho. The nearest orchard is L8 mile- distant down Snake River, while there are no orchards in the other direction inside of 75 to 80 mile-. This orchard wa- free from codling moth until three <>r four years ago, the larvae baving undoubtedly been intro- duced in old apple boxes about that time. MEANS OF SPREAD. There are -< i \ era! way- in which the codling moth can be distributed. The most prolific source of distribution comes from the shipping of fruit from an infested region. Fruit which contains the larval insects ui:i\ be shipped great distances, and when the larvae complete their growth they spin cocoon-, and in due time the moth- emerge, and with unerring instinct Beek the nearest apple trees. Many larvae are found t" have spun their cocoon- in the angles and crack- of the boxes Bui. 41, Div. of Entomology, U. S. Dept. of Agriculture. Plate II. q- ^ Fig. 1.— Apple Leaf Inhabited by Codling Moth. a, Point where larva entered midrib, at junction with one of the principal veins; b, portion of burrow exposed (photograph by Prof. A. B. Cordley). Fig. 2 —Apples Damaged by Unknown Caterpillar. (Reduced from photograph by the author.) Bui. 41, Div. of Entomology, U. S. Dept. of Agricultur Plate Eggs of the Codling Moth. Natural size of eggs at a and 6; e, showing red ring in egg: et, egg. showing the hole through which the larva emerged: h. showing the egg enlarged, with the larva inside: <>. the end of the ovipositor of the female. (From Slingerland.) 17 or barrels. In many localities it has been the practice to return to the fruit grower for refilling boxes in which fruit has been marketed. This practice has supplied the means of rapid distribution in such ocalities. If infested fruit is shipped any distance in cars the larvae spin their cocoons in cracks and holes in the walls of the car and may be carried great distances before the moths emerge. This is thought to have been the source of the infestation at Kalispell, Mont. When apples are stored by commission houses the larva? may crawl into boxes or cases of various kinds of merchandise and thus be widely distributed. In sections where the orchards are near each other the spread is accomplished by the moth flying from one to another; but when they are many miles apart, which is especially the case in the Far West, this means of distribution doubtless has little influence. The insect can probably fly a few miles with the aid of the .wind, but ordinarily 4 to miles from a source of infestation, over unimproved land, gives partial if not complete immunity. We have no authentic record of the distribution of the codling moth with nursery stock, but one can readily see how this could occur, as the larvae might be in the cracks in the ground around the trees or night crawl into the packing and thus be carried great distances. ESTIMATED LOSSES. Of all the insects affecting the apple the codling moth causes the greatest loss, and many estimates have been made of the damage. In 1889 Professor Forbes indicated an annual loss in the State of Illinois of 82,375,000. It is estimated that in 1892 the insect caused $2,000,000 loss in Nebraska. Professor Slingerland estimated that in 1897 the insect taxed the apple growers of New York $2,500,000 and the pear growers $500,000. In 1900 one-half of the crop of Idaho was dam- aged, while in 1901 the loss was much greater. Mr. McPherson esti- mated the loss in Idaho in 1902 as $250,000. In many sections of the Pacilic Northwest the annual loss is from 50 to 75 per cent. From the nature of the case it is most difficult to estimate the annual loss in the United States on'account of the many factors which enter into the problem. By taking the estimates of the annual crops of apples as given by the American Agriculturist, it is found that for the years 1898, 1899,*1900, 1901, and 1902 the average crop was 47,000,000 barrels. From 1896 to 1902, inclusive, the average price at New York, Boston, and Chicago on October 20 of each year did not exceed $2. Allowing $1 for packing, transportation, and other charges, for «The estimates under this heading have been revised from the original figures given by the author to correspond with the latest data. — C. L. M. 65U— So. 41—03- — 2 is IT. ».<»<»<» barrels at *1 we have a cash valuation of 147,000,000 for the first and second qualities. It i w ell w ithin the Limits of safety to estimate that one-fourth more apples would have been placed on the market had it not been for the codling moth. This one-fourth would he a hoi it L2,000,000 barrels, and would have no value except for cider or local sale at very low price. 'The average price for cider apples is about 30 cents, which price would yield a total of aboul 13,600,000 as the value of the windfalls, culls, and cider apples, while if they were average apples, at si net per barrel the value would he $12,000,000, showing an annual loss of about $8,400,000. The loss in home orchards, in which the percentage of 1<>— i- far greater than in the commercial orchards, is estimated at $3,000,000, giving a total annua! loss of Si L,400,000. The loss in the country at large or any section of the country will vary with the size of the apple crop. In years of full crops the com- parative injury is not so great as in years when the crop is small and the prices high. FOOD HABITS. This insect is essentially a feeder upon rosaceous fruits, and to them all of the injury is done. FRUITS INFESTED. The apple is hy far the most infested fruit. It is the natural food of the codling moth, and under ordinary circumstances is the only fruit injured, save pears. It is quite safe to assume that the larva 1 of the. codling moth originally fed upon the leaves of the apple and that the habit of burrowing in the fruit is acquired. Much has been said and written as to the resistance by different varieties of apple to this insect. In Bulletin 35, new scries. Division of Entomology, the writer gave a List of varieties and indicated the resistance. It is a notable fact that the summer varieties of apples are very attractive to the second gen- eration of insects. Varieties which are fragrant, as the Pewaukeeand Ortley (Bellflower), are always badly infested. As a general rule, one can Bay that the harder and less ripe late apples are not attacked to the same extent as those which are ripe and fragrant when the second generation enters. It i- impossible, from the nature of the case, to determine the exact ratio of resistance of the varieties. In one orchard one will find fruit of the Ben Davis variety least infested, while in another it will he the most infested. These differences are without doubt due to local conditions in the different orchards. Tear- are next in order of infestation. Under ordinary conditions they are not injured to any great extent. In the Pacific Northwest in badlj infested localities the injury rarely reaches a total of 20 per cent. When remedial measures are used this is reduced to. from 5 to L5 per 19 cent. Several pear orchards have been noted which were located in neglected orchards in which there were few or no apples. The second generation of the insect seemed to concentrate its destructiveness on the pears, and in one case fully 80 per cent and in another about 50 per cent were injured. One fruit grower in Texas reports an injury of 50 per cent. Crab apples are not usually so badly infested, but instances have been observed where they suffered fully as much. Many records also show that peaches, prunes, plums, cherries, quinces, and apricots are infested by the codling moth, but under ordinary conditions their injury amounts to practically nothing. In cases where there is a lack of apples and the infestation is very abundant considerable damage results. There are records of 4o per cent injury to peaches where the trees were quite near an apple house in which infested fruit was stored. NUT-FEEDING HABITS. There are several European records of this insect in walnuts and oak galls. In 1887 Dr. Howard carefully sifted these reports, and concluded that the evidence was not sufficient to definitely prove that the insect ever feeds upon either walnuts or oak galls: and it was highly probable that the larvae, if they were larvae of the codling moth, went into the latter for the purpose of spinning their cocoons. In 1895 Mr. Adkin exhibited a specimen of ft yorrumdla which was bred from a species of chestnut, and in 1896 gave details as to rearing this insect from walnuts, and offers the explanation that these nuts bear fleshy coats, or that the insect was originally a nut feeder. Theobald in 1896 wrote that in his investigations, extended over many years, he had never himself bred Oarpocapsa pomoneUa from walnuts, but had found both ft. gplendana and Plodia interpuTicteUa. Mr. West stated that he had also bred the insect from chestnut. Dr. Riley in 1869 recorded that he had a specimen of a moth which had been bred from the sweetish pulp of a species of screw bean (Strombooarpa monoica) obtained from the Kocky Mountains. Pro- fessor Cockerell raises the question of the correctness of this record. In 1894 Professor Bruner reported that it is highly probable that the insect feeds in the seed buds of roses. In 1901 the writer carefully searched over many hundreds of these seed buds of roses near a badly infested orchard, and did not succeed in finding a single one that wa- in any way injured by the codling moth. LEAF-FEEDING HABITS. Professor Card in 1897 recorded that the young larvae, especially in confinement, nibbled portions of the leaf. The writer has noticed many times leave- that had been eaten where he thought the work 20 was done by this insect. Professor Cordley has succeeded in making some observations upon this leaf-feeding habit which are of great value, [n a recent Letter to the writer he details his experiences as follows: It wan found on June I thai these eggs had hatched and nearly all of the larva- were dead. Two of them, however, had fed upon the leaves, were yel alive, and had made some growth, notwithstanding the fad that the leaves had Keen taken from the tree nearly a month before and were therefore presumably no1 in the most palatable < o - dition. Both larvae were feeding upon the lower parenchyma of the leaf, and one had completely covered itself with a web holding pellets of trass. A recently hatched larva, mounted in balsam, measured L.35 mm. in length; the larger of these two larvae at this time measured l.so mm. in length and was proportionately stouter. Both were transferred to fresh leaves, upon which they fed until June S, when one of them disappeared. The other continued to feed until June 1 1, when it too disap- peared. However, 1 noticed a slight discoloration of the midrib of the leaf, near w here this larva had been feeding, and on carefully opening it found the larva feeding as a miner, it ha\ Lng already excavated a tunnel about L5 nun. long. I then examined the other leaf, in which I found the Larva that had disappeared three days before likew ise feeding in the interior of the midrib. The larva- were again transferred to fresh leaves, and by the folio wing morning each had again disappeared with in a midrib. Both larva? continued to feed within the midribs until June 16, when one of them, on being transferred to a fresh leaf, refused to eat and soon died. The other, with occasional changes to new pastures, continued to thrive until June 2-"), when it was plump and active and apparently in the best of health and spirits. Unfortunately I was then absent from the laboratories for some days, and when I returned the larva was dead. I believe that with careful attention it could have been brought to maturity on a diet of leaves alone. When one considers that it lived and grew for more than three weeks upon leaves thai had bem severed from the tree sometimes for several days, and that it was apparently more thrifty between June 1(> and 25 than in the earlier days of its existence, one must acknowledge that, while the proof is by no means positive, the indications are that codling moth larva- may fully develop on a diet of perfectly fresh apple leaves without ever having tasted fruit. PI. II. fig. 1.) The writer has many times taken larvae from apples and placed them upon Leaves in cages and bottles. It was found that the larvae would fasten the leaves together with silk and oat holes in them; but on account of lack of attention no Larvae were bred to maturity. The writer believes, and agrees with Prof essor Cordley in believing, that the larvae with proper care can be brought to maturity on the leaf diet ahuie. This question of the Leaf-feeding habit of the codling moth is one of the most Important questions in the life history of the insect, and should especially commend itself to entomologists for future investi- gation, since not only will it give us a very important biological fact, but it will also prove very definitely how spraying i- effective against the insect. It ha- often been recorded that larvae gnaw cavities in rough rotten wood, bark, cloth, paper, and other places where they spin cocoons, and the bit- of these substances incorporated in the cocoons. From 121 observation it is evident that the larva* do not eat any of these sub- stances. When Paris green was placed under the band- and on the bark and in other place- where the larvae spin, it was found that none were killed, even when the poison was abundant, which tend.- to show that they do not eat of these snbstanc PRIMITIVE FOOD HABITS. Writer- have indulged in speculation a- to the primitive food habit of this insect. The other species of the genu- arc nut feeder-, and Adkins expresses the opinion that this insect was originally such, and that the habit of eating apples was acquired. The older writers have said that the insect was probably a leaf feeder. From the experience of Professor Cordley this view appears to be the more probable one. WORK OF OTHER INSECTS. There are many other insects which feed on apples whose work may be taken for that of the codling moth by those who are not familiar with the characteristics of the respective insect-: but in all instances there are differences in the work and habits of the insects by which they may be easily distinguished. The apple maggot ( TrypetapomoneUa). — This insect is quite injuri- ous in the northeastern States, and its work in the apple is characterized by many winding tunnels through the fruit. The larva is footless, and ha- no distinct head, but tapers toward the front. This maggot i- the early stage of one of the two- winged flies. The peach twig-borer (Anarsia Mneatdla). — Injury to peache- and plums by this insect is often at- tributed to the codling moth, a- it- second generation feed- in the fruit. The larvae are much darker red and much smaller than those of the cod- ling moth, and the mature larva tapers toward either end (tig. 1). The plum curcalio (Conotrachelus nenuphar). — This insect often attacks apples, but can be easily distinguished by the crescent— haped scar made in egg laying, by the small puncture- caused by tin 1 adult in feeding, and by the fact that the larva, though it has a distinct head. is footless. The Tndian-meal moth (Plodia irderpwncteUa). — This insect feeds upon edibles of nearly all kinds — meal, grain, seeds, nuts, dried fruit-. Fig. 1. — Anarsia UneateUa: a. twig of peach, showing in crotch minute masses of chewed hark above larval chambers: h. latter much enlarged: c, a larval cell, with contained larva, much enlarged: <7. dorsal view of young larva, more enlarged | from Marlatt ■. 00 etc. There is a common notion among some farmers that the larva of this insect is that of the codling moth, and the writer lias often been told that the codling moth was introduced by its larvae being imported in dried fruit. We have no reliable rec- ords of the codling moth having ever eaten dried fruit, and the Indian-meal moth is the princi- pal insect that has been reared from such sources. The caterpillar is much smaller than that of the codling moth. l.—Plodia irUcrptmcteUa; a, moth: h. chrysalis; c, caterpillar; in.'. t^;il view— eomewhal enlarged; '/. head, and <. firsl abdominal segmenl <>t' caterpillar— more enlarged (from Chitten- den . and can be easily distinguished from it (tie-. 2). Th< apple fruit-miner (Argyresthia conjugeUa). — The larva of this insect has been found attacking apples in British Columbia, and injuries which may have been caused by it have been noted in Washington, Idaho, and Montana. The larva' art 1 about one-fourth of an inch in length, are of a dirty white color, tinged with reddish when full grown, and taper at each end. The tunnels made in tin 1 fruit are numerous, ami extend in all directions. There are two species of Lepidoptera which do great damage to apples in Japan, which may sooner or later succeed in en- tering this country. Appli fruit-borer (L<"', rna hereUera), — This insect i- said to have gained a foot- hold in British Columbia. The larvae live only at the core of the fruit, injuring the seeds. When full grown they make a pas- sage «>ut. « > to 50 pel' cent each year bj this insect. The eggs are laid in clusters on the twigs and 8.— Laverna hereUera: a. adult; /<. same, sir remedial measures. Without this knowledge efforts are wasted and in some cases are a positive aid to the insects. It can not be too strongly urged that each fruit grower make himself familiar with the life history of the codling moth from personal observation, for by doing so be is placed in a position to understand the reasons for measures of control and to exercise his ingenuity in applying the same to his own orchard. The ease with which collections can be made 4 in the larval stage and the accessibility of literature pertaining to it should specially com- mend this insect to teachers as a subject for nature-study lessons. In the present studies upon this insect particular care has been taken to keep the different stages under observation in exactly the same con- ditions of temperature, moisture, and light as were present in the orchard in which the cages were located, and as a result the writer is able to present some definite data in regard to the effect of temperature upon the length of the stages of the insect under normal conditions. A.8 in other lepidopterous insects, the life of the codling moth is divided into four distinct stages- Qgg : larva, pupa, and adult. In the winter and early spring the larvae may be found in their cocoons in various places, as in cracks and holes in the trees. Later the larva transforms into a pupa, and this in turn changes to a moth, which in turn lays eggs. THE EGG. Since the time of Kocscl many authors have mentioned the egg of the codling moth and stated where it was laid, but it was as late as 1893 that it was first accurately described and figured. In L874 Mr. W. II. Iliiilbnt described the egg as being about one-eighth of an inch in length and nearly white. Riley described it as being very small and of a yellow color. Messrs. A. ,1. Cook. Koebele. Weir, and others undoubtedly siw the eggs, but Cook in L881 and Miss M. Walton doubtless -:i\\ the eggS Of SOme other insect. 25 In 1893 Professor Washburn gaye an accurate description of the ego-, with the first figure of it. This figure shows a well-formed embryo inside, but the network of ridges near the center is much too open. Slingerland in 1896 and Card in 1897 distinguished the eggs and made many observations which added materially to our knowledge of this stage. In his 1898 bulletin Slingerland publishes many excellent photographs and descriptions which caused the eggs to be familiar objects. Influenced by Slingerland's and Card's work. Aldrich, Cord- ley. Gillette, and others have from time to time added to the sum of our knowledge of this stage of the insect. It is remarkable that, in spite of the many studies of its life history, the egg escaped notice for so long and when seen was not described and figured until a com- paratively late date. The egg is a flat, somewhat oval-shaped object with a flange around it. It varies in size from 0.96 to 1 by 1.17 to 1.32 mm. Commonly speaking, it is about the size of a pin head. The surface is covered with a network of ridges which are much closer together toward the central portion than around the edge. The color depends upon the age of the embryo: as when the egg is first laid it is of a pearly white color, sometimes with a decided yellowish tinge: later it is darker on account of the red ring. The eggs are always glued to the apple or leaf and one often finds shells which remain for some time after the larva has hatched. The reflection of light from the egg is of the greatest aid in finding them, and they have often been described as reflecting the light like "trout scales/' (See PI. III.) PLACES WHERE LAID. Having never seen the egg. the early writers were forced to guess as to where it was laid. They stated that the eggs were laid either in the stem end or in or about the calyx end of the apple. These views were held because of the position of the entrance holes of the larva 3 . These ideas were published again and again for over a century, and American writers copied them until about 1897, when, by a series of observations, it was proved that they were incorrect. In 1889 Koebele and Weir stated that the eggs are laid at any point upon the apple and are " as a rule laid elsewhere than within the calyx." Washburn in 189*2 found that the eggs were "placed on both sides and the top of the fruit." In the spring of 1896 Slingerland found that in con- finement the moths laid eggs on the sides of the cages, on leaves, and on bark. Card in 1897 found that the egg> were laid almost exclu- sively upon the upper surface of the leaves, and in 1897 only 2 eggs were observed in the field. In a recent letter Professor Cordlev states that out of 15 eggs laid in confinement the greater number were 2C> ;i the fruit, and that he has never seen an egg of the first generation upon t he fruit in the field. The apparent contradictions of these observations may be accounted for by the fact that they were made upon the eggs of different gener- ations of the insect. The writer has found that in Idaho but few of the eggs of the first generation arc laid upon the fruit. In one limb cage a moth laid 21 eggs, only one of which was upon the fruit; and in another cap' -I eggs were laid and only '2 were upon the fruit. Very few eggs of this generation were observed to have been laid upon the fruit in the field. Prof essor Cordley suggests that the moth does not lay eggs upon the young fruit on account of the pubescence, which is afterwards lost. This is most probably the cause. In the tield one can often find fruit, surrounded by leaves, upon which there are no egg*, while several may he found upon the upper surface of the leaves. A good percentage of the eggs of the second generation are laid upon the fruit in the tield. When the fruit is scarce a larger number is found upon the leaves. The average of several rough countings in the tield gave an average of about 50 percent laid upon the fruit. Breed- ing records show that out of 175 eggs of this generation in limb cages on inclosed blanches and fruit there were 71 eggs upon the leaves, ( .K> upon the fruit, and i> upon the twigs. Very few eggs are laid upon the underside of the leaves, and it seems that the moth much prefers a smooth surface upon which to oviposit. We may therefore conclude that the eggs of the first generation are for the most part laid upon the leaves, while the majority of those of the second brood may be found upon the fruit. WHEN THE EGGS ARE LAID. Various writers have stated that the eggs were laid at night. Cooley records that he observed a moth depositing eggs at about sun- set. The writer's observations show that the oviposition for the most part i- accomplished in the late afternoon or early evening, while a single observation shows an v^o; to have been laid sometime between '.» and L2 o'clock in the morning. THE MMI'.KK OF BOGS LAID \'A <>\K FEMALE. There is probably less definite data on this point than on any other in the life history of the insect. Many guesses have been ventured as to the number of eggs that one female will lay, varying from 12 to :;»•<» and over. LeBaron found from t<> to 60 eggs, with an average of 50, in \ ;iiiou- stages <>f development, in the ovaries of the fem.de at the time of emergence. He adds that if all the undeveloped eggs came to maturity this number must be increased. Matthew Cooke -aid that he had :i rial in his possession in which a codling moth laid 85 27 eggs. The writer was unable to secure eggs in this way. In only two instances has the writer made definite observations on the number of eggs laid by a single female moth. Two pair-- of moth- were secured in copula and placed in separate limb cages. In one cage 21 eggs were found, but as the moth escaped the observation was incon- clusive. In the other cage 25 eggs were laid, but a spider put an end to the experiment before a definite conclusion was reached. In view of these incomplete observations the writer can only venture an opinion that the maximum number of eggs laid by one moth is about 50, with the average between 30 and 4< ». which is comparable to defi- nite records of other insects of this family. THE EGO-LATINO PERIOD. Tpon dissection of the ovaries of the female of the codling moth the eggs are found in various stages of development. It is also noted that eggs are laid when they are in different stages of maturity. From these facts we may conclude that the egg-laying period extends over some time. Various authors have given the length of time from the emero-ence of the moth to the beginning of the laying of the eo-o-s as from 4 s hours to 6 or 8 day-. Professor Gillette gives the time as about 5 days. The various records of writers show that this time varies from 2 to 7 days, with an average of from 4 to 5 day-. DURATION OF EGG STAGE. In 1746 Roesel stated that the egg hatched in 8 days. Recent authors give the length of the stage as follows: LeBaron. one week: Wash- burn. 5 to 10 days: Riley. 4 to 10 days; Slingerland. one week: Card. S to lo days: and Professor Gillette. 6 to 8 days in his laboratory, with a known temperature, and in the orchard one day longer. Cooley records 12 days as the length of the stage of one egg. The results of observations upon 164 eggs and observations of Pro- fessor Cordley are given in Table I. with the total and average effect- ive temperature to which the eggs were subjected. Table I. — Duration of egg . - 9 278 30 Sept. 6 n 10 807 27 Sept. 8 2 12 360 27 61 Sept. 8 9 11 269 24 Sept. '.' I 12 296 24 Sept. 12 32 i:» 364 24 Sept. 15 2 18 128 24 n Sept. 9 1 12 216 18 Sept. 6 11 9 269 29 Sept. 15 1 18 24 40 Sept. 8 3 10 25 1 26 Sept. 9 6 11 286 25 Sept 12 3 11 349 24 187 164 243 8 June 1 J I 298 12 15 May 12 6 286 17 The results under normal orchard temperature give the length of the stage from 9 to L8 days, with a weighted average of 11 days. This average is longer than has been given by other authors, which may be accounted for by the fact that it is the usual custom to keep the eggs in laboratories rather than under normal orchard conditions, and that the times of the laying of the eggs were estimated. HATCHING OF THE EGG. Recent authors are quite well agreed as to how the larva breaks or eats its way out of the shell. Professor Slingerland was most proba- bly the first to observe this operation. He states that the larva came out of the egg near the edge at one end through an irregular crack in the shell. (PI. Ill, es.) The writer has never observed this emer- gence, but upon examining many egg shells an irregular crack was always found which was almost always at one end of the shell. CHANGES DURING [NCUBATION. When laid the egg is of a translucent pearly color, often with a yellowish tinge. Observations upon 88 egg* show that from '2 to 5 days with a weighted average of 8 days after being laid a red ring makes its appearance. This ring appears gradually at first whitish, then yellowish, and later quite a brilliant red. By observations upon .m; egg> it was found that in from V to 1<> days, with a weighted aver- age of 8. 1- days after being laid, the egg loses the ring and in its place the larva can be seen, the "black spot/' which consists of the head and cervical shield, being the most conspicuous part. Professor Gillette states that his assistant, Mr. E. P. Taylor, found tin- n'(\ ring t<> appear in from 2 to ."» days after laying and the black 29 spot appeared 2 to 3 days later. This shorter accounted for by the fact that these eggs were kept at a perature than normal. iverage may be higher teni- METHODS OF OBTAINING EGGS. There are two ways of obtaining eggs for study. The first is to collect them in the field and place them under observation in cages. There is a serious objection to this method, as there is no way of knowing the age of the eggs. The second method, that of confining larvae and pupae and allowing the moths to emerge, is far more satis- factory. If these moths are placed in a cage over a limb of a tree, one will find eggs in abundance in a day or two. One is sometimes fortunate enough to find moths in copula, and in that event the} T should be placed in a separate cage. By determination of sex of the various moths much more valuable data can be secured. Care must be taken that too many eggs are not laid in one cage, as in that event it is difficult to keep accurate notes. ■ These limb cages are bags made of mosquito netting of finer mesh than the ordinary netting. By this method the leaves and fruit are always fresh and the conditions are exactlv the same as in the orchard. INFLUENCE OF TEMPERATURE UPON THE LENGTH OF THE EGG STAGE. It has often been stated that a higher temperature caused the eggs to hatch in a shorter time, but only a few definite observations have been recorded. The temperature used in these calculations is the effective temperature, which is obtained hy subtracting 43^ from the mean daily temperature as recorded by the United States Weather Bureau station at Boise, Idaho. Professor Gillette gives 6i days as the length of this stage at a tem- perature of from 68° to 70° F. and 6 days as the time in a greenhouse where the temperature was 110° F. at midday. In Table I the total and average effective temperature is given from the time the eggs were laid until the} T were hatched. These data are arranged accord- ing to the temperature in Table II. Table II. — Effective temperature and period of incubation. Average Total Average Total Average Total effective effective Length effective effective Length effective effective Length temper- temper- of stage. temper- temper- of stage. temper- temper- of stage. ature. ature. ature. ature. ature. ature. °F. ° F. Days. ° F. o p Days. o p o p Dai/s. 12 298 '21 24. 217 9 25 254 10 18 216 12 24 269 11 25 280 11 19 228 12 24 295 12 27 307 10 19 253 13 24 349 14 27 366 12 22 247 11 24 364 15 29 269 9 22 266 12 24 428 18 30 278 9 23 206 9 24 428 18 17 2S5 5 23 276 12 25 217 14 Average total effective temperature, 302° F. 30 This table i- not complete, in that not sufficient observations were made at lower and higher temperatures; and it is dangerous to make anv extended conclusions therefrom. A study of the table shows: First. Under a low temperature the Length of this stage is longer than at high temperatures. Second. The total temperature varies from 206 to 428 F., and the average is 302 ; and in general eggs have to be subjected to this amount of heal before they hatch, whether it be for a longer or a shorter period of time. Third. The eggs are not at the same state of maturity at the time of oviposition, as at 24 we have from 9 to 18 days as the length of stage. Fourth. Under normal field conditions a small difference in temper- ature causes but little change in the Length of the stage. MORTALITY AMONG THE EGOS. Various observers, among them Washburn, Goethe, Card, Slinger- Land, and Cordley, have found that many eggs of this insect did not hatch. There is little doubt that at least one of these writers mistook eggs from which the larva 1 had hatched for dead eggs. The writer has noted that many eggs became hard and dry, while in others the contents changed to a dark brown color. These changes may have been caused by infertility, parasites, or the excessively hot sun. The mortality as shown by our breeding-cage records is by no means so great as the writer had supposed. The eggs, however, were more or less protected. THE LARVAL STAGE. ( Jonsidering the codling moth in its economic relations, it may be said that the Larval is the most important stage of the insect. Not only is it distributed, and does all of its damage in this stage, but it is more amenable to remedial measures. At the time of hatching the young larva is from one-twentieth to one-sixteenth of an inch in length, of a semi-transparent whitish or yellowish color, with Large, shiny, black head, and dark cervical and anal shields. The body shows regularly arranged spots with short hair- or seta 1 . If hatched upon the apple tin 1 young Larva seeks a place to enter, which is in general some irregularity upon the apple or at the calyx. Slingerland, Card, and Cordley have made many excellent observa- tion- upon the place of entrance. When hatched upon the leaves they ma\ not find an apple for some time, and subsist by eating small por- tion- of the Leaves. In confinement this often occurs, but it has never been determined accurately how often it takes place in the tield. The writer ha- time and again npted these spots on the Leaves in the field, and has noted also that larva 1 hatched on leave- wonld have to Efofrom 31 10 to iJO feet before they could rind an apple: Curd notes that compara- tively few eat of the leaves in the open, but from such observations as we have the writer is strongly of the opinion that it is quite a gen- eral habit. DESCRIPTION OF FULL-GROWN LARVA. When fall grown the larvae are about three-quarters of an inch in length, and their heads measure from 1.51 to 1.76 mm. across the broadest portion. The majority are of a pinkish or flesh color, which is much lighter or absent on the under side. It was thought for a long time that the pink color was due to the larva having fed on some particular varieties of apple: but the white and pink larvae have often been found feeding on fruit from the same tree. The head is brown in color, with darker markings, while the cervical and anal shields are much lighter. The spots in which the minute short hairs are situated are but little darker than the body wall, but can be easily distinguished with a hand lens. The mandibles are the most noticeable feature of the mouth parts. Beneath the under lip is the spinneret, from which the silken thread is drawn. The larva has eight pairs of legs. The first three pairs, or true legs, are situated on the thorax, and are three jointed. Later these form the legs of the adult insect. The five pairs of fleshy abdominal legs, or prolegs. disappear in the pupal stage of the insect. The first four pairs of legs are armed with circles of hooks, while the hooks on the two pairs at the end of the body are arranged in a semicircle. The spiracles or breathing apertures of the larva are arranged on either side on separate segments of the body. (PLY, fig. 1.) ENTERING THE FRUIT. The usual place of entrance of the first generation is by way of the calyx. The larva 1 either squeeze their way into the calyx between the lobes or tunnel into the cavity at the base of the lobes. A scar, the stem, or a place where fruits touch is often selected as the place of entrance. In 1900 the writer observed an egg shell with a larval entrance hole at the edge and partly under the shell. In view of later observations it is more probable that some larva crawling around found this obstruction and entered, rather than that the larva entered the fruit directly from the shell. The second generation for the most part enter on the sides of the fruit. The larva crawls rapidly about the apple, seeking a place for entrance. A scar or roughness is a favorite place, as the jaws slip on the smooth skin. In its wanderings the larva spins a silken thread and finally makes a web over the surface of the apple. With this as a foothold it is able to make some impression upon the skin, which is bitten out in chips and dropped into the web. Later, when it is partly covered, the larva backs out of the burrow and brings pieces out with 32 it. This is repeated until it is entirely within the burrow, when it turns around and spine a silken net over the hole, in which may be incorporated -« \ «■ i u I pieces of the fruit. (PI. IV. fig, L.) Slingerland, Card, and Cordley have also noted these larvae enter, and the observations made bj the writer agree entirely with theirs. One of the essentia] points noted is that while entering none of the larvae seem to cat an\ of the fruit until well within the burrow, and it mosi probably gets some of the poison applied in spraying when it attempts t<> pierce the skin. The writer has observed numerous larger Ian ro, and is quite positive that they do not cat any of the fruit while they arc entering. PLACES OF ENTRANCE. The places of entrance of the successive broods are quite different. Various authors have stated that from 60 to 80 per cent of the larvae of the first generation enter the fruit by the calyx. In L901 several countings gave an average of 83 per cent, with a minimum of 7'.» per cent. In L902 much more extensive countings gave a maximum of '.•:; ])(■!• cent, a minimum of 50 per eent. and an average of 81 per cent. (Table III.) Less than one-half of 1 per eent enter by the stem end, while the larger remaining percentage enter the side, especially where fruits touch The majority of the second generation enter the side of the fruit. A few counts in L901 showed that the greater part of the larvae entered the side, and a few cases showed that from 90 to LOO percent had entered at that place. Countings on 1.47* apples in September, 1902, on both sprayed and unsprayed trees, are given in Table III. Table [II. — Percentagt of firsl generation entering calyx. SPRAYED Ti:i < orchard. Variety. Date. -trill. Calyx. TotaL Per <•. nt iu calj x. IftcPheroon . teler Jonathan H«n l»a\ i- do July 18 .lulv 22 July 19 •J ■1 •J 8 16 Total ... 12 88 69 B2. 6 • ITNSPR \YKI» I i;i ES .1 |> <,n.\ . .lulv 17 .lulv 19 July 21 .lulv 25 .lulv 22 .lulv :;i •J i' - J 7 21 ■1 18 100 LOO 257 15 Da Do l»r Col by 91.8 •_> 108 VIA Bui. 41, Div. of Entomology, U. S. Dept. of Agriculture. Plate IV. I Fig. 1.— Entrance Holes of Larv/£ of the Second Generation. Fig. 2.— View in Orchard of Hon. Edgar Wilson. Showing Location of Apple House in Relation to Orchard. Fig. 3.— Another View in Orchard of Hon. Edgar Wilson, Showing Location of Apple House with Reference to the Railroad. Bui. 41, Div. of Entomology, U. S. Dept. of Agriculture. Plate V. Fig. 1.— Codling Moth Larva (Enlarged About 3 Times) [fl Fig. 2.— The Wormhole or Exit Hole of the Apple ^Enlarged). Fig. 3.— A Wormy Apple, Showing the Familiar Mass of Brown Particles Thrown Out at the Blossom End by the Young Larwe (from SlingerlandL 33 Places of entrana of the second .) If the apple is upon the tree the larva* will, in by far the greater num- ber of cases, crawl from the apple to the twig, from there to the branch, and thence down upon the trunk of the tree. Another method, which is comparatively rare, 18 that in which the larva lets itself down 35 to the ground by moans of a silken thread. This may be on account of the fact that the larva 1 sometimes drop accidentally and use the silken thread to support themselves. It is not uncommon to find these threads extending through the branches of trees which are badly infested with the codling- moth. Professor Gillette finds that 85 per cent of the Larvae enter the bands during- the night, and the remaining 15 per cent during the day. in Ausrust. Observations of the writer show that in the summer the larger percentage enter the bands from 6 p. m. to about 11 p. m., at Boise, Idaho. After 11 p. m. it is usually so cool that there is but little activity. In September the conditions as given b} T Gillette are about reversed. The nights arc cold, and the larvae arc active only during the warmer Darts of the day, at which times they enter the bands. If the apple has fallen to tne ground the larva simply crawls into a convenient place and spins its cocoon. After leaving the fruit the larva is unprotected, and does not consume much time in finding a place to start its cocoon. PLACES OF SPINNING COCOONS. In orchards the cocoons are normally found in cracks or holes in branches or trunks of the trees, under scales of rough bark, and in the rough bark on the main branches of the trees. When the trunk of a tree is smooth the cocoons are often found under bits of bark and in the earth about the foot of the trees. Cocoons are found under anything on the tree or leaning against it, as bands placed around the trunk, rags tied around the limbs, or boards and sticks leaning against the tree. When much fruit h s fallen the larva' seem to have a greater range in spinning cocoons, often placing them among clods of earth, beneath paper or any other rubbish on the ground, in the cracks and rough bark of adjacent trees, in piles of wood or lumber, in fence posts, and under the pickets of fences. In piles of fruit in the orchards the cocoons are normally found placed among the apples; in orchards where the trunks and branches of the trees are smooth, the cocoons are often found in the cracks of the earth about the foot of the trees, and when fruit is lying on the ground they have been found among the clods of earth by Cordley and McPherson. Cordlev published a photograph showing a cocoon on a clod of earth. In the writer's experience two cases have been found in which a cocoon was spun inside of wormy fruit. It was impossible to tell whether or not the larvae which had spun these cocoons were those which had done the injury to the fruit. In packing houses it is quite common to find the larvae in cracks of the floor, walls, and roof, in piles of lumber or boxes, and in the angles and cracks of boxes or barrels used for han- dling tne fruit. The larva usually gnaws out a cavity in which to 36 spin its cocoon. These cavities are often found in the interior of rotten trees, stumps, and fence posts, with passages excavated into these rotten pieces of wood from 2 to 4 inches. In the spring cocoons can l>e found only in the more secure places, those spun in more exposed places having been eaten by their enemies. (See PI. VIII.) DESCRIPTION ()F Till-: COCOON. The cocoon is composed of silk, which Is the product of the pair of silk glands common in many orders of insects. These glands are sit- uated on either side of the alimentary canal, and consist of three parts, each of which bas a separate function. The cephalic portions unite to forma single tube in the head of the insect, which extends to the externa] opening orspinneret. The spinneret is a chitinous projection on the under side of the labium or lower lip. Throughout its life the larva makes use of this silk in various ways. When a suitable place has been selected for the spinning of a cocoon the larva begins to weave about itself this single thread of silk. The exterior outline of the cocoon conforms to that of the cavity or crack in which it is placed. While spinning the larva is bent upon it -elf and decreases considerably in size. When the cocoon is completed, which takes usually about one day. the larva straightens out and con- tracts in length. While the exterior of the cocoon may be rough, the interior is always smooth and oval in shape. At completion of the spinning of the cocoon the alimentary canal, silk elands, and other organs peculiar to the larva begin to disintegrate. In from 1 to 1!> days, with an average of about 6 days, the larval skin is shed and the insect becomes a pupa. The east larval skin can always be found at the caudal end of the body, shriveled into a rounded mass. Various authors have noted that when the cocoon of the codling moth is torn or cut open, it is immediately repaired by the larva. Professor Slingerland states that the damage is repaired in winter. He ha- also had a larva spin two or three complete cocoons after hay- ing been removed very early in the spring from the one in which it had hibernated. The writer had one spin two new cocoons during the summer. Professor Gillette notes that in Colorado the larva? leaving the cocoons in the early spring leave those in which they have hibernated and seek other places in which to spin new ones and pupate. He reports that under in bands placed on the trees in the early spring •'» larvae which were spinning new cocoons were taken. Various reasons might be assigned for this habit of the insect. It might lie that the cocoons are too deep in the wood of the trunk of the tree for the moth to emerge without materially injuring itself, or it may be thai the larva on becoming active in the spring finds itself in a \\<'t place, and. for either of these or some other reason, migrates t<> :i bcllci- place and spins itself a new cocoon. 37 One of Professor Gillette's correspondents reports that he tound 53 larvae under 295 bands in two weeks. Another reports 307 larvae April 2 and 409 April 17 from 2,500 hands. Gillette thinks that the number caught under these bands is too small to be of any great value as a remedial measure. DURATION OF THE STAGES IX THE COCOOX. On account of the direct influence of this question upon the system of banding, particular care was taken to ascertain the duration of the cocoon staf entering band. Number Date of Miotic larva-, emerged. Xurnber of moths. Time, Total Average effective effective tempera- tempera- ture, ture. June 29. July 14. July 22. July 29. July 31 , 1902. Aug. 6. 1902. July 19 July 21 July 22 July 30 July 31 Aug. 1 Aug. .; Aug. 9 Aug. 11 Aug. 29 Sept l Sept. 5 Sept. 9 Aug. 9 Aug. 11 Aug. 12 Aug. 13 Aug. 15 Aug. 16 Aug. 18 Aug. 19 Aug. 20 Aug. 21 Aug. 22 Aug. 25 Sept. 9 Aug. 18 Aug. 19 Aug. 20 Aug. 23 ^Ug. 1^ Aug. 19 Aug. 21 Aug. 22 Aug. 23 Bays. °F. °F. 2 20 433 21 2 • >•> 505 23 2 23 .543 24 1 If. 494 31 4 17 528 31 18 566 31 1 23 722 31 •> 18 32 : 20 645 32 l 38 1.115 29 <; 41 1.170 29 2 45 1,284 29 2 49 1.392 28 3 11 3H2 33 3 13 424 33 3 14 4.55 32 6 15 481 32 5 17 541 32 2 1^ 31 5 2ii 600 30 . 21 615 29 1 22 633 29 2:: 661 29 5 24 693 29 2 27 78 29 1 42 1.171 28 2 1^ 30 1 19 550 29 1 - 553 28 1 21 581 28 3 23 641 28 1 12 209 17 1 13 224 17 3 15 270 18 4 16 - 19 3 17 330 19 88 Table IV. Thiration of lif ofthi codling moth inside the cocoon— Continued. ■ ntering band. Number Date of larvae. moths emerged Aug. 6. Aug. IS. Aug. 15. Aug. 20. Aug. 22. 1902. Aug. 25 Aug. 26 Auk. 27 Auk. 28 Aug. 29 Aug. 30 Bept. 1 do ... Sept. 8 ....do... Bept. 12 <]<> ... Sc|it. 17 Nuiiil.tr 6t moths. Time. 1>(II/S. Total tempera- ture. 392 125 156 185 503 519 168 (171 604 607 547 633 Average tempera- ture. 24 The number of larvae used was 17<», and the stage varied from 11 to 49 days, with u weighted average of *2'2 days. This average is some- what longer than that secured by other observers, and may be partly accounted for by the lateness of the season. The principal point to he clearly shown is the Length of the mini- mum stage, which these experiments show to he not less than 1<> to 1 1^ days. The time spent in the cocoon by the hibernating larvae varies con- siderably, but usually lasts about eight months. If the larva* are taken inside and kept where the temperature is higher, moths will sometimes emerge in .January or February. IMI.ll.M IB OF TEMPERATURE DPON THE DURATION OF THE STAGE. Various authors have stated at various times that this stage might be considerably lengthened or shortened by temperature. Table V shows a preceding table arranged according to the effective tempera- tures and the lengths of time. Table V. Effective temperatun and length of cocoon stage of codling moth. Average Total A\ .TIILM- Total Average Total tempera- tempera- Days. tempera- tempera- Days, tempera tempera- Days. ture. ture. ture. ture. ture. ture. o y !■ °F. o y o y. °F. 17 209 12 ■J."» 604 •_M 2'.' l . 28 1 I.". 22 1 i:; .M7 21 80 :.:;:. 18 18 •J 70 15 607 28 600 20 18 802 L6 674 26 M 194 If. 17 •jo 17 a 19 581 21 666 L8 20 641 •l.\ 666 is 1.;:: 20 1.171 12 722 28 26 1,892 19 ::-2 IM 16 22 156 21 29 19 ■Ml 17 22 615 '21 1^ 28 633 22 646 20 661 28 I.",:, 11 22 698 21 88 362 11 ■_•:: 7^:; 1. L15 27 88 121 13 I'.- L9 I. 170 11 1 39 From the table we tind that the minimum total temperature is 209 . the maximum 1,392°, and the average 592°. The evidence given )>y this table is insufficient to warrant any definite conclusions. It is quite evident that there are other factors which have not been taken into account, of which moisture and unequal development of the larva? when the cocoon is spun are probably the most important. EFFECT OF THE INSECT UPON THE FRUIT. The effect of the injury by the codling moth upon the fruit varies with the variety of the fruit and the season of the year in which the injury iadone. The attack of the larvae of the first generation usually causes the fruit to fall. A few of the fruits of fall and winter varie- ties, after having been injured, stay on the trees for the remainder of the season, but the early varieties fall quite rapidly and readily. In all cases the effect of the injury is to cause the fruit to ripen prema- turely. The amount of the windfall of' the late varieties depends in great measure upon the amount and violence of the wind. The effect of the injury upon the value of the fruit is variable. If the inside of the fruit is eaten out. it is valueless except for use as cider apples. When the injury consists of only a small defect on the exterior of the fruit, it may be graded as second, and is of considera- ble value. Fruits often bear very small spots where the larva 1 have pierced the skin but have failed to bore into the flesh of the apple. These spots do not materially injure the apple, and many of them are packed as first-class fruit. In cold storage apples which have been injured by the codling moth are the very first to begin to rot. and are consequently sources of contamination to the surrounding fruit. THE PUPA. The pupal stage of the codling moth is that stage in which the organs that are peculiar characteristics of the larva arc broken down and worked over into the tissue of the adult. The pupa is about half an inch in length, and varies in color from yellow to brown, depend- ing upon age, and when the moth is about to emerge it has a distinct bronze color. The head, eyes, mouth parts, antennae, legs, and wings of the moth are apparent in sheaths which are immovably attached to the body. The abdominal segments, which are movable, are each armed with two rows of spines, except the terminal segments, which bear only one each. These spines point backward, and play an impor- tant part in the economy of the insect. The last abdominal segment has a number of long spines with hooks at the end. These hooks are fastened in the silk and aid the pupa in holding its place in the cocoon. EMERGENCE OF THE MOTH. After the pupa has thrust itself out of the cocoon, the pupal skin splits down the back, and the moth forces its way out by splitting 40 away the bead end of the pupal skin. The legs, antenna', and wings arc drawn <>nt of their sheaths. The insect is wet, and the body wall is soft. The wings Increase several times in size, and as the body dries it grows more rigid. A few moths were observed to have emerged in the field. During the process of expanding and growing they (dung to the bark of the trees with their heads up (PL VI, fig. I), avoiding the sunlight. When the wings were fully expanded the moths would often hold them over their hacks for a few minutes, in a manner simi- lar to the way a butterfly holds its wings. After running about over the tree for a short time the moths fly into the lower branches of the trees, and are lost to observation. Their quick and erratic flight is similar to that of other moths of this family. The whole process of emergence takes from fifteen to thirty minutes. THE ADULT INSECT. The adult insect or moth is quite variable in size. The wings expand from 14 to 19 mm. Commonly speaking, they never expand over three-fourths of an inch. The whole insect is covered with scales in varying colors. The tip of the front wings bears a large dark- brown spot or ocellus on which there are two irregular broken rows of scales, which have a coppery metallic color, and with some reflec- tions of light they appear golden. Near the ocellus there is a very dark-brown band across the wing, which is more or less triangular in outline. The remainder of the wing is crossed by irregular dark and white bands, an appearance caused by the white tips on the dark scales. Jn many specimens there is a distinct darker band across the wing, while in others this band is not apparent. The hind wings are a grayish-brown color, darker toward the margin, witli a long black line at the base of the fringe. The underside of the hind wings has dark, irregular, transverse markings. The underside of the front wings is of a light-brown color, with opalescent reflection and with a few markings except on the costa. The legs and head and patagia are covered with long, narrow, white-tipped scales, while the body is covered with white-colored scales with opalescent reflections. The huge white scales on the caudal margin of the abdominal segments are especially conspicuous. (PI. VII.) HOW TO DISTINGUISH THE SEXES. There are many characteristics by which the males and females may be easily distinguished. As stated byZeller, the males have penciled, long, black hairs on the upper side of the hind wings. These hairs are Sometimes of a light color, which renders them difficult to distinguish. Slingerland discovered that the males could also be distinguished by the presence of a distinct elongate, blackish spot on the underside of tin- fore wings, which spot consists of a number of black scales. These 41 scales are sometimes of a slate color, which under certain lights ren- ders the spot inconspicuous. There is a great difference between the genital organs of the two sexes, as the ovipositor of the female can be said to be hoof -shaped, and ends, roughly speaking, in a point; while the presence of the claspers on the male can be said to cause the abdomen to end in a line. HABITS OF THE MOTH. It is generalh' stated by writers that the adults of the codling moth are but rarely seen in orchards. In cases where the infestation is not very bad this is usually the case; but where the infestation is bad it is a very common thing to see the moths in the orchard, but never in any large numbers. They spend most of their time resting on the upper surface of the leaves or on the trunks of the trees, where they are hidden by their resemblance to the grayish bark. When disturbed, they fly away so quickly that the eye is unable to follow them in their erratic flight. According to many observers the codling moth feeds on the juice of ripe apples. The writer has often observed them drink- ing water in cages. As the conclusion of many investigations b} T man} 7 persons and under various conditions, it has been definitely determined that the insect is not attracted to lights. A very few records of captures of codling moths at lights, usually of the accidental catching of one or two specimens, have been published. DURATION OF THE LIFE OF THE MOTH. LeBaron gives 1 week as the average length of the life of the adult codling moth. Washburn gives from 10 to 15 days, and Slingerland says that one moth lived in his cages for 17 days. Records of the writer in August, 1902, of forty-seven moths, show that two moths lived 1 day; ten, 2 days; eleven, 3 da}\s; ten, -i da} T s; two, 5 days; seven, 6 days; one, 7 days; two, 8 days, and two, 9 days; giving a weighted average of -I days. The length of the adult stage depends upon the conditions under which the moths are kept, as the} 7 will live longer if there is water which they, can drink. The average of 4 days was obtained when there was no water accessible to the moths; but had there been water or ripe fruit, the average would probably have been longer. GENERATIONS OF THE INSECT. The question of the number of generations of the codling moth in one season has for many years been in doubt. In recent years ento- mologists have been stimulated to greater efforts and have in a measure solved the problem. The economic importance of this question is very apparent, as the second generation of the insect inflicts about ten 4i> times as much damage as the first generation, and it is necessary to know whether a second generation is present in order that the proper measures of control may be employed. Great biological interest also attaches to this problem, as it affords an excellent opportunity for the study of the effects of different climates on one insect. The term " generation" is used instead of ••brood** because it describes more definitely the idea intended. A generation in this con- nection means a Dumber of individuals which pass through certain stages at about tin- same time, having begun in the same stage at the beefinning of any gfiven season. A succeeding generation is the asrgrre- gate of all the different broods of the individuals of the generation immediately preceding, A new generation is considered to begin with the egg stage, and continues through all the transformations of the insect until the moth dies. Many authors object to the term "partial generation," but as there is a condition in which this term can be used with a definite meaning, it may be well to use it. For instance, in some sections of the country all the insects pass through one genera- tion; a few. becoming more advanced than others, may succeed in passing through the pupal and moth stages and lay eggs, from which larvae hatch and enter the fruit, whereas the majority of the insects hibernate as larvae and do not transform until the following spring. As those insects which enter the fruit in the fall do not for the most part complete their development, at least in the tield. they are termed a partial generation. In tabulating the results of observations in regard to the time of the various stages we find that at certain periods more individuals of a generation are in certain stages than at other times; and likewise we find periods when there are fewer insects of a certain stage than at other times. These periods are designated respectively the maxima and minima of the different generations. It is always considered that the larvae, pupae, and moths found in the early spring belong to the last generation of the preceding season and may be termed the hiber- nating generation. From the writings of European authors we find that there is but one generation of the codling moth in northern Europe, including England (Westwood) and northern and central Germany, while the evidence of Reaumur and Schmitberger shows that at Vienna and in France there are two generations. American writers have at various times recorded many observations of variations in the number of generations in the United States. Fitch seems to indicate 4 the pres- ence of but one generation, while 1 [arris says a few may transform and enter the fruit in the fall, though the majority of the lirst generation hibernate. Fletcher reports that careful observations extending over ten y.ar- convince him that near Ottawa, Canada, there is but one regular generation of the insect, while in the fruit-growing districts 43 of western Ontario there are two generations, the second being- inva- riably the more destructive. The observations of Atkins. Harvey, and Munson agree with those of Harris. Slingerland says in 1898 that his observations indicate that in New York a large number of the larvae of the first generation develop into moths, the percentage transforming depending upon the weather -conditions of the season. In 1894 Smith found by a series of observations that the larvae col- lected in midsummer did not transform further that year, but hiber- nated. Later, in 1897, he states that near New Brunswick. X. J., there is positively only a single annual generation, and. further, that south of Burlington County there is at least a partial second generation. In addition to the observations already given of conditions quite simi- lar to these in New Jersey, we find that Trimble in 1865 carried out a very careful and accurate series of experiments upon the life history of the codling moth at Newark. He found that on August 1" there were three pupae among the insects under observation, and that on August 2<) many moths had emerged: on August 23 he found that one in live of the larvae had transformed. Sanderson finds that there is one generation and a partial second generation in Delaware. He states that of the larvae found Jul}' 31 about 29 transformed and 5 remained as larva?. Taking these numerous observations and the data given in regard to them into consideration, we must conclude that Doctor Smith's observations are too few in number and do not justify the assertion that there is but one generation of the codling moth at New Brunswick. Man}' observers in widely different sections of the United States have found two generations clearly denned. Le Baron states that " in the latitude of Chicago a great majority of the moths of this brood (tirst) emerge the last two weeks in July." Riley, after many years of close observation, states that the insect is "'invariably two brooded in Missouri." Popenoe and Marlatt found two genera- tions in Kansas. Gillette indicates two generations in Iowa. Walton by breeding experiments discovered two generations in che same State. From a series of observations extending over several years. checked by breeding experiments. Cordley concludes that there are two generations at Corvallis, Oreg. Koebele says there are two gen- erations in the Santa Cruz Mountains of California, and the insect probably does not differ in its habits throughout the State. Based upon one of the most extensive studies of this question that has ever been made. Gillette arrived at the conclusion that there are two generations in Colorado. Coolev says that in VM*'2 there were two generations at Missoula. Mont. Forbes indicates a third generation in Illinois, based upon the fact that very young larvae were found on October 1. Coquillett states that his notes indicate that the insect has three generations in California. Washburn says there are three to four generations at Corvallis, Oreg. Card gives two to four in 44 Nebraska. Cockerel! concludes there are three lull generations near Mesilla Park, N. Mex. AJdrich in L900 stated thai there were three generations in Idaho, and in L903 concluded after a Beries of breeding experiments that there was a partial third generation at Lewiston. At various times writers have made assertions that in the warmer sections of the United States a partial fourth brood was produced. In carefully sifting all these statements the writer finds many points which throw doubt upon and render them of hut little value, principally because definite date- and localities are not given. The date and exact localities are often of as much importance to future workers, and per- haps of more importance, than the observation it-elf. METHODS I'.V WHICH THE NUMBER OF GENERATIONS MAI BE DETERMINED. From the nature of the case the determination of the number of generations of the codling moth is a most difficult problem to solve accurately. The methods used must he scrutinized carefully, and all possible sources of error mu-t he taken into consideration or elimi- nated. The correctness of a conclusion can he assured only by exact- ness in methods and hv corroborative evidence secured by different methods. Observations made in orchard examinations have constituted one of the methods largely followed. Although observations are of great value when used in connection with other methods, they often lead to erroneous conclusions when used alone, as it i- possible to obtain evidence of the condition of an orchard only from the study of a very small portion of it during a very short period. Past conditions are often unknown, and conclusions obtained are largely based 14)011 pre- conceived ideas. If a large number of insects can he bred throughout the season, much valuable data can he secured and the problem solved beyond any doubt. A- yet we have no records of breeding experiments carried on throughout the season with the necessary accurate data. The writer ha- attempted many times to breed the insects throughout the season, but has always failed, usually on account of some unfore- seen difficulty which caused the experiment to end. However, it is believed that with proper care and experience thi- breeding can he successfully done. Breeding the insect and harmonizing the results of the breeding hy observations in the orchard- ha- been the method most used in working upon this question. By breeding the insect through part- <>f it- generations valuable data have been secured, which, if pieced together and corroborated by other methods, are almost a- valuable as if the insect bad been bred throughout the season. Many entomologists have neglected t<> increase the value of their breeding experiments by keeping the insects under condition- of tem perat lire and moisture different from those prevailing in the orchard and keeping no record or a very fragmentary record of the tempera- 45 tures to which the insects were subjected. Many other records are questionable by reason of the fact that the generation, or the nearness to the maximum of the generation, of the insects placed in the cage was uncertain or unknown. Early in his studies of the life history of this insect the writer saw the necessity of finding some method by which the numbers of indi- viduals of a generation could be approximated at certain times. By an incidental study of the records of larvae captured under bands, published by Professor Aldrich in 1900, it was noted that at a certain time in the season there were fewer larvae so caught than at periods of time immediately following and preceding. By collecting as many records as were obtainable at that time, it was observed that these conditions were quite constant. The periods of the larger and smaller number were termed, respectively, the maximum and minimum of larva? entering bands. In 1901 many fruit growers in Idaho, at the request of the writer, kept and submitted records of the larva? killed under bands. Other records, many of which had been made without any idea of the future use to which they might be put. were collected from many sources. These records were tabulated and curves were drawn upon cross-see- tion paper, using the time as one factor and the number of larvae as the other. These curves give quite an accurate picture of the course of the insect in the orchards throughout the season. Not all of the records, however, were satisfactory, as a few of them from various causes gave data which were of no value. The curve showing the effective tem- perature at the dates at which the larva? were killed under the bands was drawn upon the same charts and gives quite accurately the effect of the temperature upon this habit of the insect. A number of these records are reproduced (tigs. 5 to 16). INACCURACIES OF THE RECORDS. There are many sources of possible inaccuracy in these records. The greatest inaccuracy is probably found in the weekly or biweekly band records, because these are composite records of many individual trees and show only approximately the dates of the maxima and min- ima. Many of the records were commenced too late in the season to be of any real value: and when they were started even a little late the curve ascends with rapidity, which would not have happened had the record been started earlier. In consequence of a series of warm days. the maximum number of larva? may enter the bands sooner than they would if the temperature had remained normal; and if the temperature be low for many days, the maximum might be later than it would be normally. Spraying might seriously interfere with the accuracy of the record, as at certain periods all of the larvae entering the fruits might be killed and thus cause a fall in the curve of larvae entering 4f> >•"- o Z ■ ^-r-. . ; , co ; ^> : : : o r -* > i ! "i - - . . i . . . oo - w ■ ~ --^.1 : : : _-—*"'■ • Koo- ~"~ —^ " > : : ' : ~ "- ■ ■ -- Ci - 1 ■ , ~=— ■■< ^ . . . o*- "^ r"^s» D : ~ i : ■" " * . .^\^-r-~ < - T ~f * o - : ;:::: yZ^ ^~~~- . : . T^sl: : : . . 7S . 1 . ::;::::::::: 1 ::::::::<* : o _ fr> - jy ..:::.: • • ■ > : _X X ^o- • ^>~t— o . -/: ::: ,_ -~~~~7^j . n ' ^rr"-"- ~^^ Ill Z 3 o Tnlllllllll : O OOQ hands. When counted the | larvae were killed, which | reduced the number of a larva- of the succeeding a generation. If the tree 1 from which the record is « taken should he covered e with rough bark or have a | Large Dumber of holes and 2 cracks in it, the number of | larva- entering the bands § will not be so great as if ^ the hand were the only | place in which they could 2 hide to spin their cocoons: > therefore, filling the holes ® and scraping away the g rough bark would cause a * rise in the curve. In most cases the con- % ditions which would ren- y, der the records inaccurate . were eliminated when it | was possible to do so. In J order to show the relations | between the daily and the g weekly band records, a = weekly summary (tig. 6) J was made of Gibson's daily 5 hand record. By this | means it was shown that | the weekly records are | only approximate, and | show the general trend of 6 the insect in tin- orchard J rather than any details. ~ One writer has suggested | that the rise and fall of t the temperature would | cause a coi-responding rise | and fall in the Dumber of * larvss, so as to obscure the | true position of the maxi- I. mum. By a study of the record made by Mr. ( rib- son (fig. 5), in which the effective temperature is shown by a dotted line, many interesting- facts in regard to the temperature can be observed. It must be noted, however, that the number of larvae caught on any given day is influ- enced by the temperature of the preceding day. as most of the larva? enter the bands at night, some time before midnight, and that they are usually killed and counted some time the following morning, while the observations upon the temperature were taken at 6 a. m. * n n -:- 5: n n u H H :: e: -: -- -: :■: 5: 15 :- 20 6 : e -. 3 U S E JULY AUG JST _ SEPT. -^::-8^I,:^ | ' \ 1 1 1 ^^^\ 1 1 1 1 ':■/■• \ \ 1 \ ■ ■ / \ 1 : * ■ ! ' \ 1 \ 1 \ 1 \ ' \ I \ \ i \ . V|^^ \ ~~ ^ ^-^^ 1 \ "*"^ > _ 1 \ . T~- — ■ ...:.....: 1 Fig. 6. — Weekly summary of Mr. Gibson's band record. and 6 p. m. The great rise which occurred on June 24 was probably due in a great measure to the fact that the bund- were placed upon the trees on the 21st. The fall in the number of larvae on June 24, the rise on June l j 7. the fall on June 30, the rise on July 1 and 2. and the fall on July 4 can be partially accounted for by the corresponding rise and fall of the temperature. From about July 5 to August 4 the Fig. 7. — Band record made by William A. George. Caldwell. Idaho, In 1901. temperature was high, but there was no corresponding rise m the number of larvae, as there were no' larva? ready to enter the bands, the majority of the insects being in the moth. egg. and younger larval stages. Thi- interval of few larva? marks the time between the maxima of the generations entering the bands. In the second maxi- mum it can be noted that the rise and fall of- the number of larva? is 48 usually parallel with thai of the temperature, but toward the end of the record the temperature has but little influence. The record made l.\ Mr. George (fig. 7) and Mr. Ajers (figs. 8 and 9) -how practically N BO a I i JULY AUGUST SEPT ■6ct. ' > M 7 B 9 pjl.ll_Hll.ri»ll trtaaffBXIWWI*. » 5 * 1 b lt1...un»^ l 7.< ' i mi ii ii m , i J J 4 L n I - t ' 13 « ll -: 9 a ; ' MX •• 3 2 I III lilll 1 II 1 II I 5 ^ _^ 1 ^v ' I / N \ . \ v 1 / N. ' v V J \ frJ I 1 NJ pj L 1 \ ^ kiii / . < i ^^^ Trk Lk v x I 8.— Weekly band record made by Mr. Aver- at Boise, Idaho, in 1897, on 140 trees. the Same conditions, but not so (dearly, on account of the length of time between the observations. LENGTH OF THE LIFE CYCLE. In order to establish a correct basis for the determination of the number of generations, it is essential that we determine as closely as Pio. v. -Band record made by Mr. Avers in li possible the average Dumber of days in which the insect can pass through one generation. Assuming a certain date, with as much accuracy as possible, when the maxima (n-cuv in a hand record, and taking into consideration all the imperfections of the records, we should have approximate!}' in the number of days between these max- 3, 4" D v. of Entomology, U. S. Dept. of Agriculture. Plate VI. Fig. 1.— Larv>£. Pup>e. and Moths on Rough Bark. Fig. 2.— Infested Apples Being Buried. Bui. 41, Div. of Entomology, U. S. Dept. of Agriculture. Plate VII. Fig. 1.— Codling Moth 'Enlarged 4 Times 1 . Wing on the right shows the reflections from the gold-colored scales in the ocellus. Fig. 2.— Codling Moths (Enlarged Twice] w^ti0mm ^|i(i|l IjHeIjUJJ Fig. 3.— Codling Moths (Natural Size, from Slingerland^ 49 ima the length of the life cycle of the insect. In the records given we find that the periods vary from 40 to about 66 days, with an aver- age of 55 days, or about 8 weeks. Professor Gillette finds thp' according to his life history studies upon the summer brood the ?:■:: :-:: Z30C :::: ::: mr JULY AUGUST SEPT. Fig. 10.— Band record made by David Brothers in Colorado in 1S99. period of the different stages is as follows: From egg to larva. 7 days: from larva to cocoon stage. 19 days; from cocoon stage to emer- gence of moth. 18 days: from emerg'ence of moth to middle of egg- Fig. 11.— Band record published by Prof. C P. Gillette, taken on 14 trees, at Fort Collins, Colo., in 1900. laying stage. 5 day- (estimated); total, 4:9 days, or V weeks. From the writer's numerous records of the lengths of the different stages, however, it is found that most are somewhat longer than those given 6514— No. 41—03 4 50 by Professor Gillette and thai the egg stage averages about 11 days; from th<> hatching of larvae to Leaving the fruit, 20 days; from enter- ing the bands to emergence of moth. 22 days; from emergence of moth to middle of egg laying (estimated). 5 days; making a total of 58 days, or about 8 weeks. By adding together the shortest times and the longest times, respectively, we find the minimum length of the life cycle to be 36 days and the maximum LOO days. This period of 55 to 58 days having been obtained by these two widely different methods, they are probably not far from the correct average length of the life eycli- of the codling moth. SEASONAL HISTORY. By following the development of the codling moth through the sea- son as carefully as possible, we are enabled to throw more light upon the question of the number of generations. Those larvae which have escaped their enemies during the winter, if left in the tield. change to Fig. 12.— Band record made by Prof, J-'. A. Popenoe, Manhattan, Kans., in isoo. pupa-, according to Slingerland, just prior to the time when the apple trees are in bloom. He found the first pupae April 27, and by the 7th of May about one-fourth had pupated. In L902 the writer found the largest number of pupae about the time the apples were in bloom. Some were found in rotten wood as late as June 10. The location of the larva has the greatest influence upon the period of pupation, those in warmer places pupating more quickly than those in colder situations. EMERGENCE OF THE MOTH. From the records of various writers, as compiled bv Gillette, we find that the first moths appeared from April 24 in New Mexico to about Mav L6 at Corvallis, Oreff. Mr. McPherson records that in L901 he found a moth in the field in Idaho as early as April 23, and that the moths were most numerous about May 1. Mr. Hitt in breeding 50 moths found that tin- first emerged May 5 and the last May 28. In L902 the writer found that the majority of the moths emerged between 51 May 15 and 2< >. Cordley states that in Oregon in 1899 moths emerged in some eases April 10, and continued to do so until July 1. At Ithaca. N. Y.. Slingerland found in 1896 that moths emerged from May 3 to June 22, and in 189^ from May 24: to June 7. Gillette records that he found moths out of doors at Fort Collins as early as April 2o. The extreme range in time of appearance of these moths was 69 days in their cages. At Fort Collins, ac- cording to Mr. Hitt's records, this period extends over about 23 days. Professor Slinger- land found that this range was 49 days in 1S96. RELATION BETWEEN EMER- GENCE OF THE MOTH AND THE BLOOMING PERIOD. Slingerland states that the moths begin to emerge in New York about the time the apples are in bloom, but the majority do not emerge until after the blossoms fall, and but few lar- vae are found to enter the fruit until about two weeks there- after. Gillette found the first moth emerging about 10 days before the trees were in bloom. He states that the majority of them emerged about the time of bloom, but effffs were found July 9, 1900, and June 19, 1901, and were all hatched by July 21, the trees having been in blossom about May 5 to 15. This would make about a month between the blooming period and the time when the a 5 g 3 O Q O o O O O O o o o 2 > <• o 1 ■ ; r ■ 1 1 1 1 o Cj c z _m Cj C \ a p K a ■ er — — L- /, . 1 — — > C o: C c III 1 ' •4 V) m P 1 ?: ~ ^ . 1 . :j____i» . __. j_~ — — - o — • ■ _ _, , ! •z. < 52 first larvae hatch and enter the fruit. Card found the eggs about three weeks after the blossoms had fallen. Cordley found that in L898 the first larva entered the fruit about July L the egg from which JULY AUGUST SEPT. OCT. 2C« 2301 24O0 2300 2200 2KM 900 800 y\ I7O0 ::::_4±::E!::::5;::::::::::::::::::::::::::::::::::::::::::::i::::::::::::::::::::::: 600 IN -\ ■ / \ -•: / \ OOC / \ * \ 000 ii.. _* 101 / \ ::::;j±::::::::::::::::::::!::::::::::::::::::::::::::::::::::::::::::::::::i: It-- s- .:.... BOO ...ill s s 500 ...[.it ^ .::...._;:;e;:;::::::::::::::::: too ::^::H::::::::::::i::::::::::::::::=:::::!:e:::::::::::::::::::::::::::=::!:::::::::::::===::::::::: 200 , it n, ... . .y :::=... ] " " n .. .. . ::::== =-: : 1 Fie 1 1.— Band record Diade by Prof. J. M. Aldrich, Juliaetta, Idaho, on 10 trees, in 1899. it hatched having probably been deposited about June 21. This enter- ing of the fruit took place about two months after the petals had fallen. The writer found that in southern Idaho in 1902 the apples were in full bloom about May L3, and the first larvae were noted to • ■ : • ; I ! ; ■ ■ ■ ; 14 1 4 1 f- r • t 1 ■••{•■ Fio. 15.— K taeof the recorda made by u E. Burke al Boise, [daho, In vac. to determine the maximum o4 the second generation. have entered the fruit June LI, or about 25 days after the blossoms had fallen. From these few observations we find that the moths may emerge -Mine time before the apples are in bloom, and. depending largely 53 upon locality, the larvae begin to enter the fruit from a week to two months after the blossoms have fallen. From the standpoint of the orchardist this is a most important question in considering the effect of the first spraying upon the insect. Fig. 16.— Record by H. C. Close, Utah Agricultural College. The next point at which we can make any definite observations upon the codling moth is when the larva 1 are leaving the fruit and entering the bands for the purpose of spinning their cocoons. The band rec- ords give this most valuable data in a very accurate manner. The following tabic shows the maximum of the different generations enter- ing the bands, according to these records: Table YI. — Maximum of larva hilled under hands. Year. 1897 1898 1 899 1901 1901 1901 1901 1901 1901 1901 1901 1901 1901 1899 1*90 1883 Locality. Observer or source of record. First maxi- mum. * £ Boise. Idaho do Juliaetta, Idaho.. Nampa, Idaho Payette, Idaho ... do do I'rovo. Utah ....do do Hagerman, Idahi Lewiston, Idaho. Caldwell, Idaho. Colorado Kansas .-an Jose, Cal Second maxi- mum. Mr. Avers ....do l'rot'.J.M. Aldrich H. G. Gibson J. Shearer do ....do Utah Agricultural College do do It. E. Connor s. G. Iasman Wm. C. George ... David Brothers... K. A. Poponoe Chapin 140 July 17 Sept. 15 1-10 July 10 Sept. 10 40 July 20 sept. 24 4 June 26 Aug. 16 3 July is Aug. 17 80 July 1 128 July 5 23. ...do... 26 July 13 34 July 5 27 July 12 4 ....do... 10 June 25 July 16 July 25 850 July 19 Aug. 30 Sept. 2 Aug. 27 Sept. 2 Sept. 4 Sept. 10 Aug. 13 Sept. 15 Sept. 28 Sept. 23 — y a = Time of re- moval of bands. < 6112. 62 20. 66 8, 51 60 61 3, 45 2 50 2 54 00 49 01 .. 65.. 247 Weekly.... 909 do 620 do 467 Dailv 215 Weekly.... 554 do 690 do 141 do 829 do 880 do 194 do 660 6 per month 640 2 to 5 days . ... Weekly.... do* do 87.48 149. 36 215. 5C 116. 75 71.66 44. 42 13. 2 180 108. 2 84.7 8.2 166.6 64 54 Rile} states thai the larvae of the first generation are most abundant about July 8; Gillette, that this occurs in Grand Junction about July L5, at Denver July 21, and at Fort Collins July 'I'k Mollis OF THE FIRST GENERATION. Card round the first moths of this generation about July '2. Cord- ley gives A.ugus( 1 as the date for the first and September L5 for the last. Gillette gives the following data: Grand Junction, Colo., first July 28, Last September L2; Canyon City, first July L5, last Septem- ber LO; Fort Collins, first July 13, last September L2. According to Gillette, the eggs of the first generation were most abundant August L2. In L901 the writer found eggs most abundant between July L5 and August 1. In L902 they were most abundant about the same time, but were obtained in caged as late as August 29. The dates of the maxima of this generation of the larvae going under bands is wrll shown in Table V] for the second generation. An examination of these band records as published shows that the period of the larvae leaving the fruit and entering the bands extends over two months. HIBERNATION. The following table by Gillette shows the time at which pupation ceased and the larvae began to hibernate at various places in Colorado. It was found, as shown by the table, that pupation ceased between August 1<> and August :i<>. varying with the locality in which the experiments were made. Table VI [.—Proportion of hibernating larva taken at different «. Do Do Rockyi ord, Colo I'- I).. Dm I'M I'" Canyon Clty.Colo.... !»<• !»-• ]>■■ I>;itrs larvae were taken. July 16-23,1900 July 24-30, 1900 July31-Aug. •'.. 1900 Aug. 6-13, L900 am-. 13 20, r.tiMi Aug.21 Aug. 30 Sept. 1,1900 Aug. 1 6, 1900 Aug. 7-11, 1900 Aug. 12 II. 1900 Aug. L5 21, 1900 AUg. 22 28, 1900 Aug.29-Sept.6,1900 July 30, 1899 Au-. 1-13, L899 Aug. II 20,1899 Aug. 21-28, 1899 Number taken. 79 ISO l '.»■_> II :.i 11. "» B0 26 70 60 L00 Number hibernat- ing. 78 130 192 I II 66 115 30 so II Record by- Silmou Smith. Do. Ii... Do. Do. Do. II. B. Griffin. Do. Do. Do. D... Do. Dr. K..I. Peare. Do. Do. Do. Cordley has for several years been unable to breed any moths after September L5. In L900 the writer found that pupation had ceased September 1. and in L901 September7. In L 902 more extensive breed- sperimente were carried out. from which it was found that pupa- tion began t<» grow less aboui A.ugus1 l and entirely ceased August l'i'. and that no moths emerged after September 17. 55 At various times records have been made of tin ding- single moths late in the season, in October. The presence of these moths can be easily accounted for by the fact that the larva- probably got into some place where the general outside temperature had no effect on them, and increased temperature caused transformation. EVIDENCES OF A THIRD GENERATION. It is often found that in September a large number of the fruit- have been entered by very young inject.-, and it is also found that in some localities these injuries extend into October. This has given rise to the belief that there is a third generation present: and not having detinite records in regard to the life history of the codling moth, many fruit growers have come to the conclusion that there are three gener- ations, and some have even gone so far a- to say that there is a par- tial fourth generation. Many entomologists have taken these state- ments from the fruit grower.-, and not having given as complete study to the subject a- was possible, have published the conclusion that three generations were present. The writer has collected all of the publi- cations in which three generation- were either indicated or given as occurring, and has, with the greatest of care, studied the observations upon which the conclusions were based. Many entomologists have submitted original notes or copies of the notes from which their con- clusion- were drawn. After carefully studying all these records and published accounts the conclusion was reached that there were only two publications in which any substantial evidence is given as to the exi-tence of a third generation of the codling moth. Professor Cock- erell. in a bulletin of the New Mexico Experiment Station, concludes that there are three generations and a partial fourth. Professor Cock- erell relied mainly upon observations, and checked these observations by breeding experiments in only a few instances. The observations, while of value, give the condition- in the orchard at irregular inter- val-, and then only for a very short period of time. Many erroneous conclusions were drawn from these observations. For instance, the finding of an empty pupa case on June 26 was considered an evi- dence that the moths of the first generation had emerged. In view of the fact that Professor Gillette finds that the extreme period of emer- gence of the moths in the spring is 69 days at Fort Collins, and that Professor Slingerland found moth in New York as late as June 22. we see that there is the greatest probability that these moths were the latter part of the hibernating generation, instead of the first part of the first generation. The finding of wormy apples on July 3 was con- sidered as the beginning of the second generation entering the fruit. On August 1l' -mall larva? in fruit were considered to be the beginning of the third generation. Anyone familiar with the conditions of Western orchards know- that small larva? entering the fruit can be 56 found almost ;mv time in the summer. From the evidence given by Professor Cockerel] the writer is of the opinion that there are only two generations of the insect present in Mesilla Park, and that there i- no sufficient evidence of a third. Professor Aldrich in a recent bulletin state- that, in his opinion, there is at least a partial third brood at Lewiston, Idaho. Th is con- clusion is arrived at as a result of some very carefully conducted experiments which give evidence, by breeding records, which up to a certain point is Indisputable. By caging the insects at proper inter- vals Professor Aldrich obtained moths of the second generation on September 3 and 4. There is no doubt in the mind of the writer that these were moths of the second generation. But Professor Aldrich failed to state whether or not he obtained eo-o\s from these moths, and instead of doing so took unknown field conditions to carry out the remainder of his experiments, taking it for granted that the larvae entering after September 6 hatched from eggs which had been laid by moths of a similar age to those emerging September 3 and 4. As the latter were 4 of the very earliest of the second gen ration, there is no reason for assuming that the larvae which entered after this time were not larvae of the retarded portion of the second generation. By using the Length of the life cycle with the data given it is obvious that these larvae belong to the second generation instead of a third. CONCLUSION. By taking into consideration the evidence which has been derived from the hand records, from breeding experiments, and observation, the writer ha- no hesitancy in concluding that there are but two gen- erations of the codling moth in the arid sections of the West, and that it remains to he proven that even a partial third generation of the insect is present in any part of the United States. The writer admits, however, the possibility of a partial third generation in the West and South, and that careful, accurate work in tin 4 future will give us bet- ter evidence upon this point and settle the question beyond a doubt. By a careful study of the temperatures for several years in the locali- ties where observations have been made upon the number of genera- tions of the insect, the writer hoped to be able to give the total temperature at which the different conditions in regard to the genera- tions might occur; but after a great amount of labor this was found to be Impracticable, principally on account of insufficient accurate observations upon the insect, and it was decided to make use of the more general life /ones in determining tin 1 distribution of genera- tions. It may be stated that the boundaries between these life zones are only approximate; that there are different gradations between them, and that as yet there are many inaccuracies in the ma]). Mr. Mai latt. from persona] experience and the observations of other ento- 57 niologist-. arrived at the conclusion that there was one generation of the insect in the transition zone, two in the upper austral, and three in the lower austral. By using the conclusions of recent years the writei finds that there -is one generation in the transition zone, with often a partial second, two generations in the upper austral, and two in the lower austral, with a possibility of a partial third. NATURAL CONDITIONS WHICH TEND TO DECREASE NUMBERS. It has often been noted that a sudden fall of temperature is fatal to a large number of the smaller larvae of the codling moth. It has been already noted that Professor Aldrich has recorded such an obser- vation. Hot sunshine and extreme dryness cause many of the pupa? in the case to die. A moist climate aids fungi and bacteria to such an extent that sometimes most of the larvae are killed by them. Larva 1 that are killed by fungous diseases are hard and mummified, and have a whitish appearance. Bacteria cause the internal organs to dis- integrate and the larva to become limp and full of juices of a brown color. NATURAL ENEMIES. ' Although the codling moth ha- many natural enemies, the number impared with those of other Lepidopterou- larvae is comparatively small. This may be accounted for by the fact that the insect through- out the greater part of it< life i< more or less protected, but when the larvae have left the fruits and are seeking places in which to spin their cocoons and when in the winged stage they are attacked by numer- ous enemies. Birds are by far the most efficient natural enemies of this insect. Anyone who tries to collect the larvae from the trunks of trees in spring will find very few specimens, but. on the other hand, will rind many empty cocoons. The writer has many times in the spring searched persistently for larvae in the rough bark and the more exposed crack-, but found practically none, although many could be secured by cutting into the holes and cracks of the tree. Riley. Walsh, and Slingerland also note this effectiveness, and the amount of good the birds do can only be estimated. The cocoons are always found, and on a close inspection of the bark a telltale hole disclose^ the story of some woodpecker's work. It has often been noted also that the same birds have made holes or enlarged the cracks in the stubs of old branches for the purpose of digging out the larva?. Plate VIII. tig-. 1. 2, •">. -how- stubs <>f branches from an old orchard near Elkton. Aid., in which these birds have done efficient work in reducing the number of larvae during the spring. Fig. 2 is especially interesting. as on close examination it shows the following points: Some time in . in the course of pruning the orchard a branch was cut away, leaving the -tub. which is 8 inches long. In the following winter and 58 Spring the stub began t<> crack and decay and the bark (o loosen. Many codling-moth larvae crawled under the bark in the fall of L901. The woodpeckers found this stub in the following winter and spring, and not only probably secured all the lame which were under the bark, but enlarged one of the main cracks in order to get those which were hidden inside. In (he fall of L902 all the hark had fallen from this stub and many more lame took refuge in the cracks. Upon examination, in May. L903, the writer found that the crack had been recently enlarged, as is well shown in the reproduction. This recent enlarging was probably done mostly by the pileated woodpecker (Oeaphehts pileatus)^ as the chips broken out were quite large, and probably required more strength than other smaller woodpeckers could muster. This stub was sawed from the tree and sent to the writer, and in the latter part of May the moths emerged, and 28 empty pupal skins were found on June 25. The writer estimates that fully 100 larvae hibernated in this stub. It is highly probable that all woodpeckers feed on the codling moth larva). Other birds, including the nuthatches, black-capped titmice, wrens, bluebirds, crows, blackbirds, kingbirds, swallows, sparrows, chickadees, and jays, may also feed upon the codling moth, especially those birds which winter in the locality where the larva? are present. Without doubt the bobwhite quail, which has been introduced into many sections of the West, also feeds upon this insect. At best our knowledge of the food habits of many of these birds in regard to the codling moth is based upon but little direct evidence; but reasoning from what we do know positively, there is little doubt that codling moths form a part of the diet of at least some of these birds. Not many years ago a movement was set on foot in the Pacilic northwest to import the German kohlmeisen into this country, as it was said to feed hugely upon the larvae of the codling moth; but because the bene- fit s derived from the bird in its native home were not clearly proven, and that it sometimes injured fruit, and also on account of many dis- astrous experiences in the importation of birds and mammals which have already been made, the majority of the authorities were con- vinced that it would be a dangerous experiment, and no further action was taken. Th<' expenditure of time and money necessary to carry out such a project would probably be more beneficial if applied to the protection of our native birds. Koebele writes that in California he knows of many small bats Hy- ing around the apple trees in the evening, taking moths on the wing, and even darting down to take moths which were upon the leaves. The writei- has often noticed bats Hying about the apple trees, but was unable to obtain any evidence that they were catching codling moths. 59 INVERTEBRATE ENEMIES. The writer has often found moths in limb cages dead with spider's silk wound around them, but made no further observations. The insect enemies of the codling moth are either predaceous or parasitic, and are quite numerous as to species, but are usually few as to individ- uals. A large number of predaceous insects in the larval stage have been observed feeding upon the codling moth, the following list being compiled from publications of various authors: Cltauliognathus pennsylvanicus. Pterostirh us California's. Chauliognathus marginatus. CalaLhius rufipes. Telephorus bilineatus. Dermestid. Trogosita corticalis. Clerid. Trogosita laiicoHis. Chrysopa. Trogoderma tarsalis. Raphidid. 1', rimegatoma rariegata. In regard to many of these predaceous insects it is doubtful whether they feed upon the living codling moth larva or upon dead specimens. At best, they do not reduce the number of the larvae to any consider- able extent. In Utah a species of Ammophila was found stocking its burrows with larva? of the codling moth. It is also recorded in Cali- fornia that 8j>hedus nevadensis was found pulling the larvae out of their burrows. Many observers have found the eggs parasitized by a species of Trichogramma. Even in its protected life the larva is preyed upon by many parasitic insects, among which are the following: Goniozus sp. P'unpla annvMpes. Macrocentrus delicatus. Bethylus sp. The writer found traces of three species of parasitic Hymenoptera which were preying upon the codling moth in the Pacific northwest, but was unable to breed any of them. Among the Diptera only one para- site is mentioned, namely, Hyp<>xt the very hot thai we can expect to accomplish. It is a prime neces- sity, in order to make recommendations of value, that the entomologist have an accurate knowledge of the life history of an insect. Not only is this necessary for the entomologist, hut it is essential for the fruit grower also to understand it. in order that he may apply recommen- dations intelligently and vary them to suit conditions. The erroneous ideas some fruit growers have upon the life history of the codling moth are sometimes startling, following recommendations simply because they are given to them, and having no idea of the reason therefor. Often they obtain o-ood results, but more often failures result; and as they do not understand the reasons for the recommendations, they are at a loss to know why they did not obtain good results. To combat the insect successfully the fruit grower must be familiar with all the stages of the insect, the sequence of the stages, where found, and hab- its and variations. lie should also be informed how the preventive and remedial measures act in reducing the numbers of the insects. With this knowledge he will be able to vary the recommended preventive or remedial measures to exactly lit his local conditions, and if any failures OCCUr he will in a measure be able to tell why they occur, and the fol- lowing year the experience will aid him in changing his methods in order to obtain better results. He will also be protected against using methods which are of no value, and will thus avoid a Large unnecessary expense. PREVENTIVE MEASURES. Preventive measures are those which not only aid in controlling the codling moth, but aid the fruit grower in training trees so as to bear more fruit, support it while growing, and produce fruit of a better 61 quality, size, and color. Although many of these questions are not closely allied to the control of the codling moth, they are of impor- tance, as anything which increases the margin of profit aids in secur- ing better general results from an orchard. There are many methods of prevention which ma}' he applied to keeping the insect out of a section of the country in which it is not vet present. By study of the means of its spread it will he learned how it may have entered the country, and by closing all possible ave- nues of introduction immunity may be secured for many years: but if fruit is being continually shipped into a new country from an infested district, it is only a question of a few years when in spite of all that can be done the insect will gain a foothold. Whether it becomes injurious or the loss is nominal will depend upon many condi- tions. Many orchardists who have planted young orchards in infested districts are quite desirous of keeping the codling moth out of their orchards as long as possible, but if there are infested orchards near by this is a practical impossibility. It may be said that money and labor spent in keeping the insect out of a section or an orchard will accom- plish more good if directed toward the stud}' of better orchard methods and adapting the measures of control to that section of the country. To insure the best results in the planting of a young orchard in an infested locality the codling moth should be considered from the very first, and everything that is done should be done only after taking into account the actual or probable presence of the insect. If note is taken of these methods and they are faithfully carried out, a great amount of labor and loss will be saved when the orchard is in bearing. There are many questions which can be decided for each locality only after all the conditions over which the fruit grower has no control, such as transportation, exposure, temperature limits, and proximity to water, have been fully considered. Although the question of soils is very important, by appropriate methods the character of some soils can be materially changed, as by cultivation, cover crops, and other means. The first question which confronts a man wishing to plant an orchard is the question of varieties, which is one of the most difficult problems to be solved. The soil, the climate, the purpose for which apples are grown, and various other factors, must be considered, each one having its own bearing upon the problem. If a home orchard, the likes and dislikes of the grower are the first consideration, but if the aim is to plant and maintain a commercial orchard, the question of varieties must be determined, first, by finding what varieties are well adapted to the locality in question. This can be learned by consulting the experiment station officials in the different States and from the experience of growers who have orchards in that locality. The next consideration is what varieties will meet the market demands and com- 62 mand the highest prices. It is ;i well-known facl that in the arid regions of the Pacific Northwest the Jonathan. Grimes Golden, Komc Beauty, BeD Davis, Winesap, and a few others are the best adapted to a commercial orchard; while in the humid sections of the same region the Newtown Pippin. Spitzenberg, and a few others have proven most successful. It might he well to note here, as has been stated before, that the Pewaukeeand Ortley apples are always found worst infested with the codling moth, while the Lawyer and Winesap are least infested. After it has been decided which varieties to plant, the next question is that of buying the stock. Good stock should always be insisted upon, and one can be sure of securing the desired varieties only by buying from well-established, conscientious nurserymen. It is preferable in the arid region of the Northwest to plant 1-year-old stock. The land usually has some vegetation upon it, such as sage brush or timber, and after clearing it the soil should be thoroughly pulverized. If irrigation is intended, the ground should be leveled and graded to facilitate irrigation. The courses of the irrigation ditches should be determined by the general contour of the land, tak- ing into consideration the future 1 routes of the spraying machine, which will draw upon these ditches for water for spra} T ing. SETTING THE TREES. There are many methods which may be used for setting the trees, the details depending on the size of the orchard and the means at hand. The essential feature of the operation is to make the holes large enough to receive the roots of the tree, so that they can still retain their natural position. After tilling and packing earth into the holes, water should be allowed to run in, to aid in giving the trees a good start. It has been found that it is a very injurious practice to place any manure in the holes when the tree is planted. If manure is to be applied in the new orchard, the best method is to scatter it over the surface of the ground. (are should be taken to Cause the trees to lean toward the south- west, from which the hottest pays of the sun come. By doing so. sun scald will in a great measure be avoided. After sun scald the bark breaks, and the wood is exposed and becomes cracked and decayed. It has often been found that trees thus affected always bear a larger percentage of wormy apples than trees on which the bark is unbroken. This is accounted for by the fact that the codling moth larva* go into the cracks to spin their cocoons and are there secure from their enemies. It is a common sight in all sections of the country to see trees planted from L6 to 18 feet apart, with the upper branches intermin- 63 gling .so as to form a dense mass of branches which can not be sprayed properly, and there is no room between the rows for wagons or culti- vators. It is strongly urged that the trees be set not closer than 30 feet apart; some growers prefer 10 feet. PRUNING. No arbitrary rules can be made for pruning on account of the fact that every kind of tree and plant, in fact every individual, presents its own peculiar problem; but there is an ideal which the pruner should endeavor to attain. It is found in many sections of the West that the trees have been allowed to fork so that there are two or three main branches, and upon bearing a heavy crop these branches have split apart, sometimes totally ruining the tree. At best, if the branches are brought back into place and held by bolts, wires, or ropes, a crack will be left, into which fungous diseases can enter and in which codling moth larvae will spin their cocoons. Such a break should be dressed with grafting wax or shellac varnish, and the branches fastened closely together. With proper pruning, when the head of the tree is being formed, this trouble may be avoided. Instead of two or three main branches, the head of the tree should be so formed as to have four to six, thus distributing the weight, and preventing breakage under ordinary conditions. Many apple growers have headed their trees too high for best results. The disadvantages of this method are that it is difficult to reach the fruit and foliage with spray, and much more difficult and expensive to harvest the fruit. Other growers have headed their trees so low that the branches spread and droop so that they are close to the ground. In many instances when there is a heavy crop of fruit these branches bend down and either touch or lie upon the ground. The result is that much of the fruit on the interior of these trees and on the under sides of the outer branches is so shaded by the foliage that the sunlight can not reach it, and a large percentage will be poorly colored and of second quality. (See PI. IX.) A mean between this high and low heading is to be desired, which will do away with most of the disadvantages of these extreme methods. In order to secure proper coloring in fruits on trees it is necessary that enough smaller branches be removed to admit an abundance of sunlight through the tops. In the arid sections of the Far West the trees grow with great rapid- ity, and if allowed to take their natural course become slender and not strong enough to support a normal weight of fruit. It has been found that by cutting back half of each year's growth the trees will be made to grow heavier and stockier, and thus be able to support the weight of a large load of fruit without any danger of breaking. e well grown, well colored, and of proper varieties, hut if not well packed these conditions are nullified. Apple growers in the Far West are confronted with rather special problems. By reason of their distance from the large markets of the United States, the price they would receive for second-quality fruit would hardly he sufficient to pay the expense of growing, packing, and shipping, and it is incumbent upon them to ship nothing except that which is Btrictly first class, packed in strictly first-class manner. The cost of transpor- tation, prevailing market price, and size of crop, however, must he taken into consideration. The methods of packing depend upon the kind of package used. Fa-tern grown apples are usually packed in barrels. From Colorado and Montana westward boxes containing either 4<> or 50 pounds are almost universally used. Some are even going further, using small packages containing half bushels of superior fruit. There are many methods of packing the fruit in these boxes, as may he required by the purchasing dealers. In all cases it is highly essential that the fruit he packed SO tightly in the box that there can he no shifting of posi- tion while in transit; that there he a decided swell in the boxes on both top and bottom if they are made of thin and flexible wood, as is usually the case in the West; that the paper lining of the box remain unbroken, and that when the fruit is opened it will be attractive to the buyer. The more progressive fruit grower is well aware of the fact that a reputation for first-class fruit can be obtained and secured only by packing such fruit and rigorously excluding all wormy or scale- infested apples. Although it is extremely difficult for a packer to put up a hox of apples containing not a single wormy fruit, it should he firmly impressed upon his mind that is the ideal to be attained,. The second-quality apples, which are usually disposed of in the local market-, are those but slightly injured by the codling moth, or undersized or uncolored. The culls and windfalls should be piled together and disposed of as quickly a- possible. They may be either fed t<> stock immediately or made into cider for vinegar. The value of these culls is considerable, and progressive orchardists count a good deal on the revenue derived from them. From the seconds, culls, and windfall- in one orchard with which the writer is familiar 67 5,000 gallons of cider were made, which sold for as high as 20 cents per gallon. One bushel of apples made from 2J to 3i gallons of cider, by means of a hydraulic press run by the gasoline engine used in spraying. If it is not possible to dispose of the culls otherwise, they should be buried in holes in the orchard and covered over with 6 to 8 inches of closely packed earth. (PL VI. fig. 2.) Occasions may arise when it is necessary to store these for some time, although the storing of such fruit should be avoided if possible. Fruit should be stored in a house in which there are no holes or cracks in the roof or walls. When the larvae inside the fruit have completed their development they spin cocoons and transform into pupa?, which in turn transform into moths. These moths emerge, and if there are cracks or holes in the house they will escape and fly to the orchard the following spring. If,- however, the house is tight it may be fumigated; or, better still, screens may be placed over the windows, and as the moths collect upon these screens, they may be crushed, or they will die if left a week or so. The writer studied two cases in Idaho in which apples were stored quite near an orchard. (PI. IV. tigs. 2 and 3.) The effect was that the following year the part of the orchard nearest the apple house was always most infested, and in spite of all the remedial measures applied there was a great amount of damage. In California it was found by Mr. De Long that in a house in which apples were stored the moths always emerged and went to the windows. Eecords were kept of these insects, and it was found that 11,974 moths were killed from April 15 to August 12. One can easily imagine what destruc- tion these moths would have caused had they been allowed to fly to the orchard. PREVENTIVE MEASURES IX OLD ORCHARDS. In all sections of the country old neglected orchards are easily found in which practically all of the fruit is infested by the codling moth. The writer is quite familiar with two typical orchards, one of which is situated in an irrigated section of the far West and the other in a humid section of the East. Although the climatic and other conditions are quite different the two orchards have many features in common. The western orchard consists of about 300 trees about 18 or 20 years old. planted about 16 feet apart each way. The branches of each tree touch those of the surrounding trees so as to form a dense mass of branches and foliage. Theformer owner of the orchard, find- ing that the codling moth destroyed the larger part of the fruit, gave the orchard no irrigation, and in consequence the trees are in a more or less stunted condition. The branches are thickly matted together, having never been pruned. The trunks and branches of the trees are 68 covered with rough scales of bark, and where branches have been cut away the stubs remain, with irregular cut ends, the branches hav- ing been hacked off with an ax. These stubs have in many- places cracked and begun to decay, thus making excellent places in which the larvae of the codling moth could spin their cocoons and hibernate. The writer once secured 20 larvae from the holes and cracks in one of these stubs. The cut ends were not given proper dressing and deca} T has taken place, often leaving large holes in the trunks and branches. Many cocoons can be found in this rotten wood, and on all the trunks and branches one can find numerous empty pupal skins from which moths have emerged. The soil of the orchard has received no cultiva- tion and is covered partly with weeds, principally prickly lettuce. The orchard is very productive and always bears a good quantity of fruit, but, being undersized and from 90 to 98 per cent infested by the codling moth, practical^ no revenue has been derived from it for the past live or six years. In 1900, 1901, and 1902 the writer searched carefully for uninfested fruit, and each time found on the tree near the trunk only a dozen or so small stunted apples which had escaped the codling moth. Other insect pests are present in this orchard, each requiring special treatment. The eastern orchard is situated in a good horticultural region. The trees number about 300, and are probably about twenty-five years old. They are placed 40 feet apart, and have made a good growth. The trees have received some pruning, but as in the western orchard there are many stubs left, and there are numerous decayed holes in the trunks and branches. In many trees the branches are matted together and shade the fruit. The soil is in fairly good condition and lightly sodded. Until the past two or three years the orchard has been remarkable for its productiveness, but a large percentage of the fruit was small and much the larger part of it was infested with the larvae of the codling moth. The treatment that these orchards should receive to bring the cod- ling moth under control is about the same. It may be stated that if the preventive measures advised for a young orchard had been faith- fully and intelligently carried out man}^ of the existing conditions would not have been present. TREATMENT OF OLD ORCHARDS. The first thing to be done to old orchards is to prune the trees in such a manner that the sunlight and spraying solutions will have easy access to the foliage and fruit. Every other tree in the western orchard should be cut down. The stubs of branches should be sawed off close to the trunks and burned in order to destroy the hibernating larvae contained in them, and the cut ends remaining on the tree cov- ered with shellac varnish or grafting wax. The holes in the trunks 69 and branches should be filled with cement, plaster, or clay, in order that the insects inside may be confined and die, and that other larva* later in the season will be unable to enter to spin their cocoons. The rough bark on the trunks and branches should be scraped away and burned. In both of these orchards it is a noticeable fact that the woodpecker- have been very efficient in digging out the hibernating larvae. (PI. VIII.) It has been often noted by authors that early in the spring it La almost impossible to find larva* of the codling moth under the rough bark and other exposed places in badly infested orchards. Instead of finding the cocoons with the larva' inside, one will find empty cocoons with a hole through the bark of the tree, showing that the insect has fallen prey to woodpecker.-. All places in which the larva* might spin cocoons should be destroyed or rendered unsuitable, and the larva? forced to spin cocoons in exposed places where the wood- peckers and other birds can get them. The soil in these two orchards should receive about the same treat- ment, except that irrigation should be begun in the western orchard. They should both receive a very shallow cultivation for about one year, with a dressing of manure. The cultivation should be so -hal- low as not to injure any of the roots, which may be quite near the surface. The second year, red clover, cowpeas. or some other legu- minous cover crop should be sown, and every third year this may be turned under, thus adding available plant food to the soil. When these methods are followed the recommendation given for an orchard in bearing should be adopted. At best the preventive measures can not control the insect in an orchard, but they are valuable adjuncts which render the measures more efficient. REMEDIAL MEASURES. Remedial measures against the codling moth are those measures from which little or no benefit is derived except in saving fruit from the ravages of the insect by killing it. MEASURES ()F LITTLE OK NO VALUE. The codling moth seems to have been common in orchards for many centuries, but no one made any suggestion- a- t<> how it- ravages might be checked. The first recommendations made were of no value, and it is interesting to note how the.-e recommendations have recurred at various periods in popular writing-. Many of these remedies, having little or no value, are taken up by companies, given all the benefit of modern advertising methods, and thoroughly distributed before the fruit growers become aware of their worthlessness. In order that the fruit grower may know what not to do as well as what he To should do, a Dumber of the more prominent of these inefficient methods arc briefly discussed. It has often been recommended that ninth halls be hung in the trees in order to keep the moths away. If there were any virtue in this remedy, SO many of the moth halls would have to he hung on each tree, to do the work, that the expense would reader it valued Smudging the orchard, or burning ill-smelling compounds so that the fumes will pass through the tree-, has been practiced to some extent. The theory is that the moths will he kept away by the fumes and go to other orchards to deposit their eggs. It is quite evident that as soon as these fumes are blown out of the orchard the moths will return if they have left, and in order to produce any results it will he necessary that the smudge he continued practically throughout the season. Plugging trees with sulphur or other compounds and plugging the roots with calomel have been practiced to some extent, on the theory that the sulphur or calomel will he taken up by the sap, distributed through the tree, and prove distasteful or poisonous to the insect. Trustworthy scientific experiments have been carried on which show that it is absolutely impossible for the tree to take up any amount of these substances, and little or no effect upon the insects results. The writer has found several orchards in which the trees were banded with tarred paper, the evident intention being to keep the larvae from getting up into the trees. Knowing the habits of the insect when in its Larval form, we can see that this method is ridiculous, and instead of being a detriment it is a positive aid to the insect; in many cases larva? were found which had spun cocoons under the hands, which formed a place in which they were comparatively free from the attacks of their enemies. There seems to he a popular idea among many farmers and fruit growers that all insects are attracted to light. Based upon this idea, there have been many recommendations to keep tires burning in the orchards, or to arrange Borne sort of a trap lantern by which the insects are to he attracted to the lights and fall into water on which is a film of kerosene and thus he killed. This scheme of trap lanterns was exploded many years ago, hut it seems that at intervals somebody revives it. and its fallacy must he exposed afresh. By carefully experimenting with trap lanterns and determining the catch as accu- rately a- possible it is found that the majority of the insects caught are either decidedly beneficial varieties, or are males, or females which have already deposited their eggs, and that hut few injurious insects aie caught, and none in any great number. Probably the most exten- sive experiments with trap lanterns were those conducted by Professor Slingerland. Among i:'». <><><> insects he was not able to recognize a single codling moth. This is the usual result of all these experiments, 71 and we can say without any hesitancy whatever that the fanner who uses these trap lanterns or tries to experiment with them is simply wasting his time and money, as the method has been thoroughly proven ineffective. It is also the practice to some extent to put cans or bottles contain- ing molasses, cider, vinegar, or some other substance of similar nature in the orchard, and upon finding that insects are attracted by these compounds and killed, many fruit growers think this is a good remedy for the codling moth. The results of many careful experiments show that only incidental captures of the codling moth are made. With both these last two practices — that is, trap lanterns and baiting the moths — the greatest trouble has been that the fruit growers are not acquainted with the codling moth in its early stages. An} T fruit grower can breed moths for himself, and by comparing his catch can very easily satisfy himself. Many times fruit growers have tried spraying their orchards with ill-smelling compounds with but little success. These compounds are always more or less expensive and have never been so efficient as to justify their use. Other fruit growers think that spraying the orchard with water frequently will give relief from the attacks of the codling moth. Undoubtedly if the trees were kept in a spray all the time, the fruit would be clear of the insect; but if this were done, the probabilities are that no fruit would set. and if any should set it would not ripen well, and the trees themselves would probably die. The expense of this operation would be many times greater than that of spraying. It has been stated that electric lights repel the moth and that trees near electric lights in cities are often free from its work. The writer had an excellent opportunity to investigate this point, and found that an apple tree about 4:0 feet from an electric light was as badly infested as any other in that vicinity. In order to do away with the labor entailed by using bands around the trees man} T kinds of traps have been invented. Riley, by careful experiments, showed that one of these traps would not catch as many larvae as the bands; and other experiments have shown that these patent traps are never very efficient. It was claimed for some time that the flowers of plants of the genus Physianthus might be efficient against this insect, since in order to reach the honey of the flower the proboscis would have to be passed through a narrow cleft, from which it could not be withdrawn, and the moth would therefore be held a prisoner until it died. It was proposed to train the vines around the trunks and branches of the trees, and, the moths being captured, the orchard would be protected. Conclusive evidence has been recorded which .-hows that these flowers have no attraction for the codling moth. It has been suggested thai the codling moth might he controlled by bacteria] and fungous diseases. From the facts thai the insect leads such a protected Life and that fungi and bacteria have given so few positive results in this connection it is almost useless, with our present knowledge, to even theorize upon the value of these agencies. In general it may be stated that entomologists have at all times tried experiments with these different plans and are unanimous in their conclusions. If anything new and efficient is ever perfected by which this insect may be more easily controlled, no doubt entomolo- gists will be its first advocates. MEASUKES OF VALUE. By taking into consideration all the habits and variations of habits of the codling moth in its different stages we find that, like other insects, there are certain stages in its life history in which it is more amenable to remedial measures than at others. We find that it can be best attacked in the larval stage, although some experiments indicate that something can be done when it is in the egg stage. Cook found that by spraying an apple tree weekly from May L5 until the end of June with a strong soap solution he succeeded in preventing the infesta- tion of a single apple by the larvae. In laboratory experiments with kerosene emulsion Card secured good results against the eggs. Gillette also obtained good results with kerosene emulsion. The results of these experiments have never been put to practical use for many rea- sons. The kerosene emulsion would probably be so strong, in order to have any effect on the c<> trees (in the West, where they are considerably larger than trees of the same age in the East) can be easily sprayed in one day. Some fruit growers tell the writer that they have been able, when they found it necessary to work more rap- idly, bo spray 900 trees per day. By a series of observations it has been found that it takes from four to five minutes to till the tank by means of the filling pump, and the same amount of Liquid can be sprayed out in from thirty to forty minutes, upon from 60 to N " trees, depending on their size, using about 2.1 gallons per tree. In an irri- gated orchard it is quite desirable that the ground he allowed to become dry before the spraying is begun, and thus avoid miring the machine in the soft earth, which will frequently occur in wet places in the orchard, especially when the tank is full. The cosl of these complete machines varies with the cost of the engine and pump and their fittings. They can be purchased for from about $260 to $500. The machine with which the writer is most familiar cosl $320, which included a $40 wagon and filling pump and attachments at $20. With good care and proper repairs these machines can be made to last for several years. In a working day of ten hours it was found that a 1^-horsepower engine consumed about 1 gallon of gasoline. Although tin 4 initial expense of this outfit is greater than that of the hand-power outfit, it will be found to be much cheaper in the end. as the engine can be made to more than pay for itself by other uses when spraying is not in progress, such as running the cider press, feed cutter, and cream separator, sawing wood, turning the grindstone, and numerous other tasks about a farm for which power is desired. The machinery can also be removed from the wagon and stored in an outhouse and the wagon used for other purposes. WATER SUPPLY. The distance of the water supply from the orchard is one of the greatest factors in determining the rapidity with which spraying can be done. With the water supply some distance away much valuable time i^ lost in going to and fro to till the tank. In the smaller orchards, where but little spraying is done, the usual custom i- to drive the wagon to a ditch, pool, or well, where the water is trans- ferred into the spraying tank with buckets. .Many fruit growers have found it advantageous to draw their supply of water from an ele- vated tank into which water is pumped by a windmill or piped from some Bpring or stream. For irrigated orchards the water is usually taken direct from the irrigating ditches, sometimes from the main ditch and sometimes from the lateral ditches running through the orchard. By taking the water from these laterals in the orchard the routes of the spraying apparatus in operation can be largely deter- mined, the foreman trvine at all times to be near one of them when 79 the tank becomes empty. By means of the filling pump on the cho- line power outfits much valuable time ran be saved in the operation of filling the tank, as compared with the method of having an extra wagon to haul water to the spraying outfit, sometimes employed. The routes followed by the spraying machine in the orchard depend upon many factors, such as source of water supply, position of hills and ridges, and direction of wind. Each orchard is a problem by itself. and experience will show which routes can be followed with the least loss of time. APPLICATION <)F SPRAY. There arc many methods of spraying the trees. In following the chosen route through the orchard some use four lines of hose, com- pletely spraying four rows of trees at a time: but it lias been found in actual practice that on account of the long hose and the great dis- tances the men have to walk other methods are more advantageous. Many use two lines of hose, and men standing on the ground go com- pletely around the trees, thus spraying two rows on all sides. Other fruit growers drive down one row and spray half of the tree on either side: coming back on the other side of the row they spray the other side and one-half of tin 1 next row. It ha- been clearly shown that this method gives the best results, both in the saving of time and in com- pletely covering the trees. When the trees are tall it is quite neces- sary that the men ride upon an elevated platform, and it has also been found advantageous in using the gasoline-power outfit to have the men ride on the apparatus. In this way not only the men are saved unnecessary labor, but from their elevated position they can spray the tree- more thoroughly. With the nozzle- set at an angle on the bam- boo extension, part of the tree can be sprayed as it is being approached. Then on stopping at the tree the whole side can be sprayed, and when leaving it the last part can be sprayed and spraying be begun on the next tree. It is almost impossible to spray while moving at right angle- to a strong wind, and if such a wind is encountered it will be found desirable to have the wagon go either with or against it and take advantage of it by allowing it to blow the mist through the tree-. Experience on the part of the operators will enable them to devise method- to reduce the time without impairing the effectiveness of the spraying. The ideal to be attained in applying spray is to cover the tree with a thin coating of the spray solution, so that when the water dries it will leave a coating of poison on every portion of the foliage and fruit. When the spray is applied with but little force the stream does not break up into sufficiently fine globules, and when they strike the foli- age they either cover only a -mall portion of it or run together into large drops and fall to the ground, leaving but little of the solution on the tree, and that little very much scattered. If, however, the spray 80 1h applied with great force, the Btream is broken up into a fine mist, which, if well directed, is evenly distributed over the foliage and fruit, and upon drying leaves i more or less uniform coat. If the nozzle is held close to the foliage, the force causes it to spread well, but the coating is not so uniform as that which is derived from the mist. In spraying one-half of a tree the mist drifts through the tree from the side which is being sprayed, and in that way the tree is well covered, having received practically two incomplete sprayings. If fruit is allowed to grow in clusters it is necessary to apply the spray with great force in order to secure good results. MATERIALS FOB SPRAYING. CONTACT [NBECTI4 ' Contact insecticides are those which kill the insects by touching them. Kerosene emulsion and solutions of whale-oil soap are the sub- stances that have been most used for this purpose; hut on account of the expense, the necessity of frequent application, and the fact that the insect can he more easily and effectively reached in other stages ] »\ other insecticides, these kinds of spraying solutions have been used but little against the insect. ARSENICAL SPRAYS. The arsenical sprays contain arsenic as their essential ingredient. Other chemicals are mixed with the arsenic for the purpose of pre- venting it from burning the foliage or are products incidental to the numerous compounds of arsenic which were 1 used for other purposes than spraying, there are many spraying compounds of which arsenic is the base on the market, but there are many others which the fruit grower can make for himself by combining the necessary ingredients. "Paris green is probably the best known of these arsenicals. It has been used for many years with success, and is a definite chemical com- pound of arsenic, copper, and acetic acid. The composition is usually quite uniform, but many instances have been found in which it was adulterated or the percentage of soluble arsenic was dangerously high. AiJ indicated by its name, it is a substance green in color. It is a rather coarse powder, which has the fault of settling rapidly in the spraying tank. It is quite necessary to use linn 4 with Paris green in order t<» counteract the burning effects of the free arsenic. Paris green is comparatively expensive; in the Bast it costs about -J" cent- a pound and in the West 25 cents. Paris green may be prepared for spraying as follows: Paris green pound.. l Lime pounds.. l to Wane gallons.. LOO to 260 Bui. 41 , Div. of Entomology. U. S. Dept. of Agriculture. Plate X. Fig. 1.— Band on which the Remains of 330 Cocoons were Counted. Fig. 2.— Pupa in Cocoon on Underside Fig. 3.— Larva and Pup/e in Cracks of a Loose Piece of Bark. in Bark, from which Rough Bark has been Removed. Bui. 41, Div. of Entomology, U. S. Dept. of Agriculture. Plate XI. Fig. 1.— Gasoline-power Sprayer, Showing the Engine and Spray Pump. -Same Sprayer as in Fig. 1, but Seen from the Other Side, Showing Filling Pump and Attachments. GASOLINE-POWER SPRAYING MACHINES. Bui. 41, Div. of Entomology, U. S. Dept. of Agncu : _-e. Plate XII. Fig. 1.— Gasoline-power Outfit in the Orchard. Fig. 2.— Filling Tank by Means of the Filling Pump from an Irrigation Ditch. Fig. 3.— Hand-power Spraying Outfit, in which the Pump is Mounted Upon a Barrel on an Ordinary Wagon. SPRAYING OUTFITS IN USE. 81 The lime should be fresh and slaked in small quantities as needed. By mixing a small quantity of water with the Paris green until a paste is formed it is much more easily distributed in the water. The lime ma}' be added to the water in the proper quantity. A good average strength of this solution is 1 pound of Paris green to 150 gallons of water: but for trees with delicate foliage, such as peach, it is advisable to use a much weaker solution. Many fruit growers are using Paris green of the strength of 1 pound to 100 gal- lon-, with the addition of lime upon apple trees, without burning the foliage. Sc/u < /> '■•< < n i- a similar preparation to Paris green, but differs from it in lacking the acetic acid. It is a finer powder than Paris green, is much more easily kept in suspension, and the cost is only about half that of Paris green. There is but little of this insecticide manu- factured and placed upon the market. L<>n<>i\ it is advised that they be purchased In ion-pound using 600 gallons of spraying solution a^ a basis. Taking the prices of these different compounds as they arc in the Far West, the foil \\ ing estimates arc made: Pai is green: Paris green, I pounds, at 25 cents $1.00 I J inc. S ] m»u l ids 04 T< »t ;i I 1 . 04 Scheele's green: Scheele's green, I pounds, at 12} cents 50 Lime, s pounds 04 T< »tal 54 Lime arsenite: White arsenic, I } pounds, at Hi rents 15 Lime, ■'> pounds 015 Additional lime, 12 pounds 06 Total 225 Lime arsenite with soda: White arsenic, 1} pounds, at 10 cents r> Salsoda, 6 pounds, at 1 \ cents 09 Additional lime, 6 pounds 03 Total Lead arsenate: Arsenate of soda, 2\ pounds, at 10 cents 25 Acetate of lead, <> pom ids. at 12 cents 72 T« >tal !<7 Prepared lead arsenate. 36 pounds, at 20 cents 7.20 From the foregoing quotations, any fruit grower can estimate the expense of spraying by changing the prices to those prevailing in his vicinity. The prices of these chemicals, excepting the lime and sal soda, are from about 2 to 5 cents per pound more in the West than in the East. The labor of preparing, which is but little, is another factor which musl i>e included. In the preparation of arsenicals for a home orchard or a small commercial orchard it may be advisable for the fruit grower to purchase the more easily prepared compounds, such as 'aris green or prepared lead arsenate, as this does away with much trouble and loss of time in preparing the .solution. Labor is the principal element of cost in actual spraying operations. The cost of one spraying for a thousand s year-old trees in the far West, using 2 J gallons of lime arsenite and soda compound per tree, timated as f<»ll<»w-: 85 Hand-power outfit: Man and team 4 days, at $3.50 $14. 00 Two men 4 days, at $1.50 each 12. 00 Materials 1-12 Total 27.12 Gasoline-power outfit: Man and team 1 J days, at $3.50 5. 25 One man 1£ days, at $1.50 2. 25 Materials -' 1. 12 Gasoline, lh gallons 55 Total 9.17 The above estimates are taken from actual conditions in the field, and the prices of material and labor are based upon current rates in the far West, where they are considerably less than in the East. It is assumed that the men and teams were employed at the local rates; but as men and teams are already employed upon fruit farms, the actual expense of these spraying operations is much smaller. Accord- ing to these estimates one spraying would cost 2.7 cents per tree if a hand -power outfit is used, or 0.9 cents per tree if a gasoline-power outfit is used. The additional cost to the fruit grower would be much less than this, and in some cases would probably not amount to more than 1 cent per tree with the hand-power outfit, or one-half cent per tree with the gasoline outfit. TIME AND FREQUENCY OF APPLICATION OF SPRAT. The time of application of the spray is one of the most important con- siderations in the work. It has been found that in many sections of the country fruit growers have sprayed without any definite knowledge as to when the spray would be effective, and many times it was not at all so, the effectiveness that it had depending more upon chance than anything else. Other growers follow the empirical rule of spraying once every two weeks after the blossoms have fallen. If this rule is followed no doubt many of the sprayings during the season have little or no effect upon the codling moth. It can be readily seen that to be effective the poison must be placed upon the trees so that when the larva? are hatching they will get some of the poison; but if they are already inside the apples or in their cocoons they suffer very little from the spraying. Hence we find that where there are but two genera- tions of the insect there are only two periods in the season when a large proportion can be affected by the poison, and these are the proper times for spraying. The work done at these two periods may be termed the early and the late sprayings, the early spraying being- directed against the first generation of the codling moth. Two sprayings at the early period are advised, one a few days after the blossoms have fallen and before the calyx closes, and the other 86 about t\\<> weeks later, when the majority of the larvae are entering the fruit. There baa been much discussion recently in regard to dis- pensing with the spraying immediately after the blossoms have fallen. It has been found that the larvae enter the fruit from one to two months after the blossoms have fallen. In cases of bad Infestation, where preventive measures have been neglected, or there is an abun- dance of the insect, it might be well to make three sprayings while the second generation is entering the fruit. This period varies with the locality and with the seasons in the same locality: hut there are a few methods by which the time can l>e approximated with sufficient accu- racy, and in view of the fad that the time Is Variable the w liter does not w i-h to recommend that the spraying he dispensed with until each locality is studied. Spraying may he begun immediately after the first new entrance holes of the second generation are found, or about twenty days after the date tin' maximum of the first-generation larvae are found under the bands ready to spin their cocoons. The larvae of the second generation in southern Idaho usually begin to enter the fruit the last week in July, hut the majority enter in August, and hut few in September. The number of sprayings to be made against this generation depends entirely upon the success achieved against the first generation. It has been found quite definitely that the injury due to the second generation is much greater than that from the first gen- eration; and if the injury due to the first generation is from 2 to 5 per cent the writer advises a third spraying for the second generation; hut if the injury has been only 1 per cent or less, two sprayings will he found sufficient. The quantity of lime used in these late sprayings should be reduced to a minimum, as lime on the fruit depreciate- its market value. Light showers wash hut little of tin 1 spray from the tree; hut if there is a heavy shower or continued lain, a large amount will he removed, and it will he necessary to repeat the sprayings as soon as possible. Lead arsenate is less affected by rain than the other spray- ing compounds. llow THE eoisoN KILLS THE QH9ECT8. Though Paris green has been used for spraying purposes for many year- with SUCCeSS against the codling moth, it is Only recently that any serious effort ha- been made to ascertain how the poison is obtained i>\ the larvae. Slingerland was the first to answer this ques- tion with any degree of accuracy. According to him the spray lodges in the saucer-like calyx when the young fruit is erect after the blos- soms have fallen, and up<>n the segments or leaves of the calyx clos- ing the poison is held there for some time. As about 80 per cent of the larvffi of the first generation enter tin 1 fruit through the calyx, it i- easily seen how the majority of them would obtain some poison. 87 Calyces were analyzed and the poison found in them, showing that the closing of the lobes incloses some poison at least two weeks after the spraying has been done. The writer is unable to find any pub- lished record of any larva 1 having been found in a calyx, which were killed or supposed to have been killed by the poison. The evidence which goes to show that they are killed is all indirect. In Idaho in 1902 the writer gave special attention to this most difficult point. By examining the apples immediately after the blossom had fallen it was found that the calyx proper consisted of two parts: first, the calyx tube, which we may say i^ on the interior of the apple, and then the lobes or bases of the lobes which support the stamens. The stamens stand close together and form a sort of roof over the calyx tube. The writer has many times (ait open this calyx tube after spraying- has been done, and was unable at any time to distinguish any particles of spray inside the tube. The writer is also unable to give any definite figures as to what percentage of the larva enter the apple by way of the calyx tube, but it is possible that it is large. The differ- ence in percentages of larvae which have entered the calyx on sprayed or unsprayed trees should indicate the efficiency of the spray. Table III gives 82 per cent as entering the calyx on sprayed trees and 80 per cent on unsprayed trees. There was lack of data in regard to the sprayed trees, which was not discovered until it was too late to obtain a new series. Cordley rinds that the larva do not enter the fruit until two months after the petals have fallen, and on that account does not recommend the spraying immediately after the blossoms have fallen. How the larva of the second generation are killed is a question still in a somewhat chaotic state. It is generally believed that the larva get the poison when they enter the fruit, but the observations of many investigators, including the writer, show that when the larva 1 are entering they eat little or none of the fruit. In both sprayed and unsprayed orchards it is quite common to find places where they have entered the fruit and have died shortly after entering. Countings on 4:26 new entrance holes in sprayed trees showed that there was an average of 40 per cent of the holes in which the larva had died, and in two counts this percentage went as high as 7<>. Other countings on unsprayed trees gave, out of (MM) new entrances. 11 per cent in which the larva had died. As there is no way of knowing accurately how many of these holes were caused by larvae which entered the fruits where two apples touched, these data can not be relied upon, but the writer believes that during the period in which the entrance holes were made at least 10 or 15 per cent of the larvae succumbed to the spray. Twice larva were found dead before they had entered the fruit. "Many times early in the season holes were found, the making of which would employ the larvae for several days. In these cases it is questionable whether or not the spray killed the insects. In regard to the entrance of the second generation, the Larvae may get some of the poison when their jaws are slipping on the fruit in the attempt to make an entrance, hut at best the percentage probably killed in entering the fruit can in no way account for the general effi- ciency of spraying. Considering the egg-laying habits and the leaf- feeding habits of the larvae of both generations, the writer is strongly of the opinion that by far the larger number of the larvae killed by spray are killed through eating or nibbling the poisoned leaves before they find fruits. Ii is to l>e hoped that future years will develop more definite data on this subject. THE BANDING SYSTEM. A- before Indicated, upon leaving the fruit the larva seeks some place in the crevices or loose bark in which to spin its cocoon. This fact was known as early as 174»*>. hut ii was not until L840 that Bur- relle, of Massachusetts, discovered that by winding something around the tree or placing (doth in a crotch many larva 1 would he induced to collect there and could then be destroyed. lie recommended destroy- in' them in a hot oven. The banding system was further studied and elaborated by Dr. Trimble, who recommended hay ropes for hands. Very soon this became the most successful method used, and up to about L880, by its use many fruit growers were able to save consider- ably more of their fruit than before. Many other observers have made studies of these hands and proved what was best in the way of material and the manner and time of application, until now it is one of the very best adjunct methods in the control of the codling moth. Generally speaking, the system of banding is simply furnishing the larva a good place in which to spin its cocoon and killing it after it ha- done SO. (See PL X.) The materials used for these bands may be designated as temporary and permanent. The temporary hand- are composed of hay. paper, or any other cheap material, and. after the Larva? have entered the hands, are burned with the contained larvae. Permanent hand- are usually of doth: these, after the larvae are killed, are replaced on the tree. The materials for these hand- are various, and it has been found that the most efficient is some dark, heavy material. Bands of thin muslin are quite inefficient. Professor Aldrich recommends In-own canton flannel. In orchard practice it is found that fruit growers use almost any material, such as old clothes, burlap, and canvas. ( me of the most essential feature- o\' the banding system i- to render all other place- on the tree unsuitable \'^v the spinning of the cocoon. thus ha\ in-.-- the band the only alternative. Cracks in the tree should he filled, the rough hark scraped awa\ . and all other obstacles removed. 89 The band should consist of a piece of cloth long enough to go around the tree more than once, and from 10 to 1-L inches in width. This piece of cloth is folded once lengthwise and placed around the tree. There are many devices for holding the bands) in place upon the tree. The one which gives the most satisfaction, and allows the hand to be removed and replaced most readily, consists of driving a -mall nail through the ends of the band after wrapping it around the tree, and then nipping off the head of the nail in such a manner as to leave a sharp point. Subsequent removal of the band is accomplished by -imply ; I 'S\ Tig. 1*.— Large apple tree properly banded for the codling moth (original). — Al-ple tree banded, showing bands both above and below a hole in the trunk (original . pulling the ends off the nail, and replacement by pushing them down again over it. Ordinarily one band to the tree is sufficient in general orchard practice, but in cases where the trees are large and have a number of large branches, it is advisable to put one band around the trunk and one around each of the larger limbs. (Fig. 18.) Where there are holes in the trees which can not be rendered unsuitable for the spinning of the cocoons, it is the best to put bands both above and below them. (Fig. 19.) 90 Manx writers have experimented upon the effect of several bands ii|x»n the tree. Le Baron gives the following table: Table VIII. Number of larva caught under band*. Date of examination. Aug. 11. Sept 9. Sept. 28. Kunl- .'ii liml- i:: '.'I 31 18 21 7 I.". 21 I Middle band* .... ■V ( )n a single t ree, from Jul\ 4 to July 23, t he same writer found 1 1<» larva- under the top band and L50 under the lower hand. The author states that the windfalls in every ease were left as they fell. In the season of the year when a Large number of the wormy apples were on the ground the lower band caught most of the larvae, while during duly, when the windfalls caused by the first generation had hardly begun to fall, the larger number of larvae were caught bv the upper hand. Professor Aldrich experimented upon one large tree and five hands. The table made from these experiments is here given* Table IX. — Professor Aldrich' 8 r<<-<,r4 larvae about ;)<> per cent were caught on the upper hand, and the lower hand caught more than any of the inter- mediate one-. The experiment also shows that iii seeking a place for their cocoons the larva 1 will cross several bands, and as there is no way by which those going up the tree and those going down can be separated, no exact percentages of such can be given. Wickson found by carefully conducted experiments that while 2,704 apples and pears were counted from which lar\;e had escaped, there were only L,188 under the bands, or 44 per cent. The remaining p.rc.nt either found other places in which to spin their cocoons or were destroyed by their enemies. The percentage of larva- caught upon a tree will depend entirely on the condition of the tree. If the tree is five from cracks, holes, and rough hark, more larvae will he caught; while if there are other places in which they can spin, fewer of them w ill go under the hand-. It ha- been fully demonstrated that in badly infested orchard- of the West only a comparatively -mall percentage of the fruit can be -a\ ed l»\ hand- alone. 91 After the larvae have collected under the bands they must be killed or the bands will become a positive aid to the insert. The usual method of examining- the hands is as follows: One end is removed from the nail and rolled hack upon itself around the tree. As the cocoons, larvae, and pupa 1 are exposed they are cut in two with a sharp knife or crushed. Many methods have been devised by which these hands can he collected in wagons and brought to a central place, where they are put in hot water, run through wringers, or some other device used to kill the larva 1 : hut in view of the fact that many of the worms will crawl out in transit, and comparatively few of them remain attached to the hands, these methods must give way to the one described. Another important point is the length of time which should intervene between the examination of bands and the killing of the larva 1 . This time depends entirely upon the length of time which it takes the larva to emerge as a moth after having left the fruit. In the warmer sections of the West 6 or 7 days has been recommended. By extensive experiments carried on by Professor Gillette and the writer it was found that practically none of the moths issue until after 11 days from the time they entered the bands. The data upon which the recommendation of 6 or 7 days was based have in some cases been found to be quite inaccurate. AY hen the trees were exam- ined not all of the larva 1 were killed, and the second week afterwards some of them were found to have emerged, and from this the conclu- sion was reached that some of them went through the cocoon stage in 6 or 7 days. The experiments by the writer and Professor Gillette have been found in practice to allow a small number of moths to escape. A person examining bands frequently can easily tell whether the time is too short or too long. If the time is too long, man}' empty pupa cases will be found projecting from the band, whereas if the time is too short most of the insects will be found in the larval stage, not having had time to transform to pupae. EXPENSE OF BANDING. When compared with the cost of spraying, banding is comparatively expensive. One man can examine the bands and kill the larvae on about 300 trees in one day. Counting his wages at $1.50 per day. we find that it costs about £5 a thousand trees for one examination, which is about half the cost of one spraying. The bands should be placed upon the -trees in the spring at about the time the earliest larva of the first generation begin to leave the fruit. This time is usually about two weeks after the first wormy fruits have been noted, and in south- ern Idaho is about June 15. It is always well to apply the bands a week or so earlier than there is any necessity for. The bands should be examined every ten days and the larvae which have collected in them killed. This makes about ten or eleven examinations of the bands in the course of the season. Examination after the first week 92 in September is unnecessary in southern [daho and practically all of the Pacific northwest, as \r less isolated and hut little infested use the banding system as a means of control. One of these is Mr. I. B. Perrine, of Blue Lake. [daho, who lias had great success in keeping the injury in the worst infested section of his orchard down to less than 3 per cent. The most important use of the hands is as an adjunct to spraying in a badly infested orchard when it is desired to bring the codling moth under control in that orchard, or in general practice when the trees are large and the spraying can not he well done on account of either the inefficiency of the spraying machine or the height of tin 4 trees. However, the writer, by many extensive experiments, lias clearly demonstrated that when four or five sprayings are made with the gasoline power outfit, and the spraying solution is thoroughly applied at the right time, banding is unnecessary. In orchards where spray- ing is the only remedial measure used it is advisable to keep bands on four or live normal trees, killing the larva 1 at stated intervals and recording the results, SO that the hand record may act as an indicator for the conditions in the orchard. PRACTICAL TESTS. The season's work in L900 may be summed up in saying that the work accomplished simply outlined the problem of the codling moth in tin' Pacific northwest. In L901 tin 4 apple crop was so unusually small that all practical tests which had been begun were abandoned, and the time devoted to a study of the life history ^( the insect and planning a campaign for the following year. It was decided to give the recommendations of previous years a thorough practical test under actual field conditions from the fruit grower's standpoint. Some dif- ficulty was experienced in obtaining orchards in which to work. Keeping in view the idea that the codling moth i- the greatest injuri- ous factor in the commercial orchard, a large amount of work was done in such orchards, the principal part in the orchard of the Wilson Fruit Company, near Boise, Idaho, through the kindness of Hon. Edgar Wilson, and in that of Mi-. Fremont Wood. Mr. McPherson's orchard and that of Mr. David Geckler were visited frequently and observations made. Their were many orchard- in various localities in which no mea8ui*es were used against the codling moth, and these were used a- checks upon tie- sprayed orchards. In Idaho the injury 93 by the codling moth in 1902 was (mite variable, as there had been but a scattering fruit crop the year before, and consequently a lack of insects in some localities. The orchard of the Wilson Fruit Company, which is a type of the very best commercial orchards in Idaho, was planted in 1894 by Hon. Edgar Wilson, and was sold by him to the company which is the pres- ent owner in the early spring of 1902. Mr. Wilson acted a< manager for the orchard company for the season, aided by Mr. W. F. Cash. This orchard consists of 650 Ben Davis tree-. 500 Jonathan. 750 Rome Beauty. 141 Northern Spy. and 800 trees which were planted as Wolf River, but were subsequently budded to Jonathan, and have not yet come to bearing. There are three short rows of Pewaukee. and a few trees of other varieties scattered throughout the orchard. The house in which the apples were packed and the culls >tored in the fall of 1901 is about 200 feet from the orchard and has always been a source of infection for it. (PI. IV. figs. '2 and 3. ) Early in the season of 1902 Mr. Wilson purchased a gasoline-power spray outfit and prepared to give the orchard a thorough spraying. The improvements made by Mr. Wilson and Mr. Cash have rendered this machine one of the most efficient for this purpose. A single spraying was accom- plished in about four days, using lime arsenite with soda exclusively a- a spraying solution. About ^.U<»<> very heavily loaded trees were in bearing. The conditions of the previous season were such that there was an abundant supply of insects present in 1902, except in the Rome Beauty section. The writer estimated in 1901 that from 40 to 60 per cent of the fruit in the Jonathan and Ben Davis sections was infested, no late spraying having been made: and the small amount of fruit in the Rome Beauty section was all infested. No bands were used, except upon the trees left unsprayed and a very few near the apple house. The blossoms of the Jonathan and Ben Davis were fully open about May 10, and had dropped about May 20. The Rome Beauty blooms through a longer period of time, and some blossoms were observed as late as June 1. Spraying should have begun about May l!'. but on account of continued rains it was delayed until the 23d. at which time the orchard was given a thorough spray- ing. After two weeks the orchard was again sprayed, at about the time the first Larvae were beginning to enter the fruit. By the 1st of July about all of the larva? of the first generation had entered the fruit. Countings on the Ben Davis and the Jonathan section gave an average of a little less than 1 per cent infested, while tin 4 Pewaukee trees, which were unsprayed. had from 20 to 26 per cent infested. The Jonathan tree nearest the apple house had about 5 per cent wormy, but this percentage decreased rapidly in the surrounding trees. Other orchards in the same condition showed from lo to 50 percent wormy: while orchards in which no remedial measures had been applied, and in which no insects were left over from the year before, showed a very 94 small percentage wormy. In the last week of July, at about the time the second generation was beginning bo cuter the fruit, a third spray- ing was made: and the fourth spraying was made about August s . at which time a demonstration was made to visiting fruit growers. About ten days after the spraying a dashing rain washed oil a consid- erable amount of the spray. Mr. Wilson and Mr. Cash did not think it advisable to make another spray, in view of the fact that the results already secured were ^<> satisfactory that they thought it unnecessary. There i-- no doubt in the mind of the writer that if this spraying had been made the results would have been better. Harvesting began about the second week in October, at which time the final results were obtained. Many trees were selected early in the season and the wormy fruit upon them counted: hut as the season progressed the number was reduced on account of the lack of time to make the proper countings. The following table Is compiled from the results upon six average-sized Ben Davis trees which were situated about the center of the Hen Davis section. At all times the greatest cart' was exercised in making these countings as accurate as possible, every one of the apples being counted and no estimates made. Table X. — Infested <nt>i< 3 (i 19 L43 21 410 123 431 His 4.8 26 :::::::::::::: 171 1.107 1,150 , tit; 533 599 1.777 237 13 :; " 4 in 11 L67 26 10 1 37 n; 7 63 26 B 41 12 ... 192 '.'77 l. Ml 37 60 97 1 ,2 1 1 229 11 1 12 4 L29 4 138 in L65 11 19 ii > l . :»:.-.» 86 L48 179 1,433 181 10 ~~T 22 17 ::n 65~ 16 28 63 87~ 28 25 26 . i 12 :::::::: 168 1 . 228 li»7 1,662 13 19 7 171 l'.i 82 16 111 101 L6 l'.'l 1,210 1,884 806 l . 892 269 11 95 The large amount of free fallen apples on trees No. 1 and No. '1 are due to the apples picked otf in the process of thinning. The average total per cent infested throughout the season for these trees wa> 13. The greatest difficulty was met with in obtaining any reliable esti- mate upon the general results from the orchard, for the reason that the larger percentage of the seconds and culls were graded as such because they were small or uncolored. The Ben Davis section pro- duced 1,944 boxes of strictly first-class fruit, and the writer estimates that this was only about one-third of the total produced. In one sec- tion of the orchard there were trees in which the loss was fully 25 per cent at harvesting time, but there were many others in which the loss was not over 5 per cent. The writer estimates that at picking time about 10 per cent of the fruit in this section of the orchard was infested. In the Jonathan section 2,030 boxes of first-class fruit were packed, and the culls were estimated at 146 boxes. By numerous counts it was found that only about half of these were infested, which gives a total of 73 boxes of infested fruit. As a general result. about 3 per cent of the apples were found infested, and the total per- centage for this section of the orchard was probably about 5. It was found that the tree nearest to the packing house was about 50 per cent wormy, but the percentage diminished rapidly toward the center of the block. A few trees which could not be well sprayed on account of their situation with regard to irrigating ditches were more wormy than others. In the Rome Beauty section, in which there was a small crop the year previous, a total of 3,017 boxes of first-class fruit was packed, and it was estimated that one-fourth, or 1<>9 boxes, of the culls and seconds were infested, or about 3 per cent of the whole crop. The Pewaukee apples were practically 1< >< ) per cent infested at the end of the season. The apples were counted on an unsprayed Domine tree September -I. and 81 per cent were found infested. From experiences in other orchards with this insect, the writer believes that, had it not been for spraying, the fruit in this orchard would have averaged from 80 to no per cent infested. (See Pis. XIII. XIV. XV.) In Mr. Cash's orchard, which is separated from the Wilson orchard only by a road, it was found that the Jonathans were 25 per cent infested, only two sprayings having been made. The orchard of Mr. Fremont Wood, which i» a type of the best of the smaller commercial orchards, was kept under observation through- out the season. This orchard consists of about 1,000 trees, the larger per cent of which are Jonathan. These trees were set out about 1895. In 1901 the crop was small and was almost totally destroyed by the codling moth. In 1902 a hand-power spraying outfit was used (PI. XII. tig. 3), which was supplemented by banding. The sprayings were made about the same time as in the Wilson orchard, except that the last -praying was after the rain, about the middle of August, and 96 it was probably more efficient on that account. A.fter the first genera- tion of the larvae had entered the fruit, it was found that there were not over 3 t<> :» wormy apples per tree. Harvesting was begun in October, and at that time it was found that in the Jonathan section, w hich consisted of about '."»«» t rees, there were 4,700 boxes of first-class fruit packed. Of culls and windfalls there were about 900 boxes, of which, from numerous counts, it was estimated that about one-half, or :» per cent of the entire crop, were infested. Mi-. McPherson's and Mr. Geckler's orchards are types of old com- mercial orchards in which the trees are large and the infestation bad. It was only with difficulty that remedial measures could he applied efficiently, as preventive measures had been neglected. In both instances, on account of the height of the trees and t heir closeness, the sprays could not be well applied. Mr. Geckler estimated his loss as high a- 50 per cent, while Mr. McPherson lost as high as 30 per cent on the same varieties. In both of these orchards there is a con- stant supplv of insects from other orchards, and their control requires radical application of preventive and remedial measures. Mi-. J. A. Fenton estimates that his crop was only about 15 per cent injured in L902, he having used bands and spraying. Mr. I. L. Tiner, who has a small orchard in the city of Boise, estimated that he saves about 80 per cent of Ids fruit each year. Mr. Gus Goeldner, near Boise, estimates that he saves 90 to 95 per cent of his fruit each year. In many sections of the West estimates have been made by fruit grow- ers in which they say they save from 85 to 98 per cent of their fruit. Sometimes these estimates are obtained from countings, but more often they can not be relied upon, the fallen fruit not having been taken into consideration. The results of practical tests in these orchards show that with four or five thorough sprayings, preferably by a gasoline-power out- lit, from about 85 to 95 per cent of the fruit can be saved from the codling moth. By a series of applications of these measures even this margin of loss may be reduced; but the saving of 90 per cent of the fruit under present conditions may be considered a solution of tin 1 problem. RESUME AND CONCLUSION. The codling moth, which is now a cosmopolitan insect, was intro- duced into the Pacific northwest about L880. On account of the warm climate t wo overlapping generations are produced, and if proper meas- ures of control are neglected the insect, under normal conditions, will infest practically the entire apple crop of many localities. The preventive measures are fully as important in controlling this insect a- the remedial measures. Bui. 41, Div. of Entomology, U. S. Dept. of Agnco ture Plate XIII. Bui. 41, Div. of Entomology, U. S. Dept. of Agriculture. Plate XIV. - o r o - 23 tro < ^< > 33 S o o H ' = 33 Bui. 41, Div. of Entomology, U. S. Dept. of Agriculture. Plate XV. Clean and Wormy Apples from Tree No. 6. Wilson Orchard. Showing 8 boxes of clean apples and 1 box of wormy apples from the tree, and 1 of clean apples and 1 basket of wormy apples from the ground. isket Bui. 41, Div. of Entomology U. S. Dept of Ag- . Plate XVI. 97 Remedial measures which are of value have been found to be spray- ing with arsenitea and banding. Spraying by the use of a gasoline- power outfit has proved to be the most effective, such spiking, using lime arsenite wkh soda, having reduced the injury in a certain orchard which had previously been from 40 to 60 per cent to 10 per cent. By the use of proper preventive measures, spraying and banding, for a number of years, the injury due to the codling moth can be reduced from nearly 100 per cent to 5 or 10 per cent in an orchard in an} T locality. BIBLIOGRAPHY OF MOST OF THE MORE IMPORTANT CONTRIBU- TIONS TO THE LITERATURE OF THE CODLING MOTH. The following bibliography down to 1898 is practically a duplicate of that published in Professor Slingerland's Bulletin 112, Cornell Agricultural Experiment Station, pages 63-69: 1635. Goedaerdt. Metamorphosis Xaturalis, Vol. I, p. 98, fig. 46. Apparently the first published account of the insect. It seems to have escaped notice until 1864, when Werneburg referred to it in his •Beitrage zur Schmetterlingskunde." Lister added nothing of importance in his Latin edition of Goedaerdt published in 1685. 1728. Frisch. Beschreibung von Allerley Insecten in Teutschland, part 7, pp. 16-17, PI. X, figs. 1-5. Grotesque and yet quite accurate descriptions of moth and larvee: believed it preferred to work in unhealthy or injured fruits. No definite data on life history. 1736. Reaumur. Mem. pour servir a L'Histoire des Insects, Vol. II, pp. 484, 496-499, pi. 38, figs. 11, 12, and pi. 40, figs. 1-10. Good account of work of larva in fruit and in making its oocoon. Two broods indi- cated. 1746. Roesel. Insecten-Belustigung, Vol. I, part 6, Xo. 13, pp. 33-37, pi. 13, figs. 1-5. In accuracy of detail and coloring the hand-painted figures equal, if not excel, any colored pictures of the insect published since. Good account of original observations upon its life history; thought the newly hatched larva sometimes entered the fruit beneath the eggshell, and that the worms sometimes left one apple and went to another fresh one. One brood indicated. All stages, except the egg, well described. 1747. Wilkes. The English Moths and Butterflies, Book I, class 1, p. 5, no. 9, pi. 65 (copies of Roesel' s figures). Probably the first English account; brief compilation from Roesel. Gave to the insect its name of " codling moth," from the codling tree, which is also figured. 1758. Linne. Systema Xatura?. Ed. X, p. 538, no. 270. Tinea pomonella, "Alis nebulosis postice macula rubra aurea." Original description of the insect when it received its first scientific name. 1791. Brahm. Insektenkalender, Vol. II, p. 465. Brief account with many earlier references. Common and sometimes destructive in orchards; and records its habits in fruit rooms. 1802. De Tigxy. Historie Xat. des Insectes, Vol. IX, p. 256. Largely a compilation from Reaumur and Roesel. Says eggs are laid on fruit before petals fall. 1805. Bechstein and Scharfexberg. Xatur. der Schiid. Forstinsekten, Part III, pp. 753-755. Mostly a compilation from Roesel and Brahm. 1818. Hubner. Verz. Bekaunt. Schmett, p. 375. 6514— No. 41—03 7 98 1819. Ti 1 re. Massachusetts Agricultural Repository and Journal, Vol. V, 364 \ i ■ i .: i r. • 1 1 1 1 > the Hr-t account of the Insecl In American literature. Previous American writers had credited tin- plnm curculio with the cause <>f "wormy apple-." Records some original breeding experiments by which he was led to conclude that the cause ol most "f the wormy apples In Massachusetts waa a moth, and n<>t a beetle <>r curculio. ' 1825. Thatcher. American Orchardist, second edition, p. 116. Records finding the worms <>n 1 1 1 « - trunks "i" trees, and therefore advises scraping off the rough bark and washing trunks with Forsyth's composition. Apparently the first notice' oi the Insecl In horticultural hooks, and the firsl one to make any recommendations ior controlling the h 1826. Kiuin and 6pen< b. [ntroduction to Entomology, III. p. 123. 1829. Trkttbchkk. Die Schmetterlinge vod Europa, Vol. VIII, i>i>. lfii-ms. Many references t>> earlier literature. Descriptions. Brief compiled account of life history. 1831. CounS. Brit Entom., VUI, pL 362. 1833. " Ki -n< i b." Entomological Magazine, Vol. I, pp. 144-146. a very good detailed accounl of the life habits of the insect. Eggs laid in the calyx CUD, < toe brood. Apparently the first important article in the English literature. 1833. Botjchr, Garten-Insekten, pp. 113-114. Brief compiled descriptions and account <>f habits. All that can he done to control it is to collect and feed out all wormy fruit as fast as it falls. 1834. &HCPHEN8. 111. Brit. Ent Haust, IV. p. 119. 1837. 8CHMIDBEBGEE. In Hollar's Naturg. 'lor Bchad. Tnserten. (For English translation Bee Loudon and Westwood's edition of Kollar, pp. 229-232, date 1S40). <. 1 general account. Two broods indicated. (He published an earlier and more complete account in his Natur. der Obst Bchfid. [nsecten, to which we have not had ace. - 1838. Westwood. Gardiner's Magazine, Vol. XIV. pp. 234-239. Mostly a K<'«>d compilation from the accounts by Reaumur and " Rusticus." ( toe brood indicated. 1840. Burrrllr. New England Farmer, Vol. XVIII, no. 48, June •">. ]>. 398. "<>n the Curculio." Records breeding the moth. One brood only. Apparently the tirst one to suggest the famous ■•handing" method. 1840. Ratzkbueg. Die Forst-Insecten, Vol. II. pp. 234-236, pi. 14. fig. 7. Very good genera] account. Believes there is but one brood in North Germany, and doubts Bchmidberger's account of two broods in South Germany. 1841. Harris. Insects of Massachusetts, pp. 351-355. (In the editions oi 1852 and L862 ro change occtj Wry good general account Only one brood indicated. 1843. GaYLOBD. Trail-. N. V. State Alt. ><>c. p. 158. Hrief accounl \\ ith Westwood's figure. Recommends allowing swine to run in orchard. Insect then common in New England, hut very rare iii the Middle State-. 1844. L&w. Bchadliche [nsecten, pp. 239-241. Largely a compilation from Roeeel, with good discussion of remedies. 1845. Downing. Fruits and Fruit-trees, p. 66. Briel account. 1846. Morris, Mi-. "Old Lady.") American Agriculturist, VoL V, February, pp. 6 I account, with original observations, and illustrated by what is probably the tir-t original Bgure of the insecl to appear in American literature. 1849. ( !oi i . Lmerican Fruii Book, p Brief account. Reports it numerous In New England and along the seaboard, and ommon In the Middle State*. 99 1850. Simpson. The Horticulturist, Vol. IV. p. 567. Brief account of breeding experiments. Two or three broods indicated. Discovered that a cloth in the crotch entic-fd many worms, and after experiments with wax recom- mends that trees be sprayed with whitewash to rill blossom end of fruits and thus prevent egg laying at this point. 1855. Nokdijugkb. Kleinen Feinde der Landwirthschaft. pp. 339-346. One of the best and most complete accounts which have appeared in the German literature. Very good discussion of remedies. Bel: -de brooded in Germany. 1859. Jaeger. The Lite of North American Insects, pp. 179-181. Brief, quaint account. 1861. Goureau. Les inseetes uuis. aux Arbres fruitiers. pp. 118-121. Very good general account. One brood in France. 1865. Trimble. Treatise on the Insect Enemies of Fruit and Fruit Trees, pp. 103- 139. Three full-page colored plates. One of the best accounts in the American literatuie. Detailed notes on birds as enemies of the insect: 'hay bands" devised and experiments recorded. Bred two broods at Newark. N. J. 1867. Boisduyal. Essai sur L'Entomologie Hortieole. pp. 560-563. Fairly good general account. One brood. 1868. Walsh and Riley. American Entomologist. Vol. I. pp. 3-6. Evidence in favor of allowing hogs to run in orchards. 1868. Walsh. Report on Insects of Illinois, pp. 27-2V*. Arguments for two broods in HI:: 1869. Riley. First Missouri Kept on Insects, pp. 62-^7. Good general account. Two br< 1869. Walsh and Riley. American Entomologist, Vol. I. pp. 112-114. Very good general account, illustrated by Riley's well-known figures. Two broods. 1870. Riley. American Entomologist, Vol. II. pp. 321.322. Records experimental proof of two broods in latitude of St. Lotus, and •. ban" r trapping the worms. 1871. Taschbnbkbo. Ent. fur Gartner und Gartenfreunde. pp. 310-313. Good general account. Admits but one generation in Germany. (The same account occurs in his Prak. Insektenkunde. III. pp. 228-231; date. 1880.) 1871. Zeller. Stettiner Entomologische Zeitung, p. 55. 1872. Riley. Fourth Missouri Report, pp. 22-30. Good discussion of bands. \Vier*s trap, lights, jarring, and the enemies of the ins 1873. Riley. Firth Missouri Report, pp. 40-52. Records careful experiments with different traps on trunk, and the discovery para- 1873. LbBabok. Third Report on Insects of Illinois, pp. 167- One of the best accounts in the American literature: based largely upon original vations. 1875. Saunders. Report Ontario Entomological Society for 1874, pp. 43-50. Good general account, largely compiled from LeBaron and Riley "s writings. Two broods in Canada. 1875. Cook, A. J. Report Michigan Penological Society for 1S74. pp. Io2-160. One of the be^t accounts in American literature. 1 I upon original ol tinns. Records seeing the eggs, but does not describe them. 1878. Thomas. Seventh Report State Entomologist of Illinois, p. 260. Two generation.", indicated. 1879. Woodward. Rural New-Yorker. Feb. 8 I Proc. West. N. Y. H<>rt. Soc. for 1879, p. 20). First published account of successful use of poisons Paris green ) against the codling moth. LOO 1880. Cook. American Entomologist, Vol. 111. p. 263. Also published in 1881 in Proc. Am. A~. A.I. Bci. for 1880, p. 669; and in Kept Mich. Hort. Soc. for L880, p. 136. Eteoordi !ii>' successful use "i* London purple to destroy the insect; iiri-< ."it! i . Die schad. und nutzlichen [nsecten, pp. 121-122. Brief general account. 1881. Cooke, [nsects injurious to California Fruit and Fruit Trees, pp. L3-19. One of the best discussions of the habits and methods of fighting it hi our literature, ticallj the same accounl was published by the author in 1879, and again in 1888in hit in.uk on •• Injurious insects, " pp. 102 108. 1 Three broods Indicated. 1883. BA1 NDEBS. [n8ectS Injurious to I'ruit-. pp. 127-133. Verj g 1 general discussion. 1883. Chapin. Report Second Annual Convention of California Fruit Growers, pp. 17 Detailed Account of an extensive experiment with bands and gathering Infested fruit; over 15,000 moths caught in a fruit room in one Beason. 1883. Wai.t..\. Miss. Report [owa Horticultural Society for 1882, pp. L99^-203. Good genera] account, witli some valuable breeding experiments. 1883. Codlingmoth inCalifornia in L883. Ann. Rep. State Board Hort. Cal., p. is. 1883. Chapin. Progress of the orchards of California during L883. Ann. Rep. Cal. State Board of Hort.. p. L2. 1883. Manning, Jacob W. Repelling and destroying codling moth. Trans. Mass. Hort. So,-., p. 10 ft 1883. Godfrey, A. N. The codling moth. Kansas Hort. Rept. for 1883. p. 91. 1883. Gillet, Felix. The greatesl pest of California insect pests, or the codling moth. In First Ann. Rep. State Board Hort. Cal., p. 72. 1883. Dec Snow. F. II. The codling moth or apple worm. In Quart. Rep. Kan. state Board Agr. 1884. Atkins. Report Maine Board of Agriculture for L883, pp. 356-363. < toe of the most Important contributions t<> the American literature: it is based entirely upon original observations. One full brood and a partial second one indicated. 1884. LiNTNEB, J. A. Apple Worm. Country Gentleman for Oct 30, vol. 49, p. 897. Letter from n. C. S., Crozet, Va., In reference to enemies of the worm. 1885. Gibasd. Traits d'Entomologie, Vol. [II, pp. 714-716. Good general account. I >ne brood. 1885. Codlin moth (in Victoria, Australia). Report of the Secretary for Agricul- ture. 1886. Cbawpobd. Report on Insert Pests in South Australia, pp. 32-39. • k>od general account. 1886. Whitehead. Report on trisects, prepared for Agricultural Department of < rreal Britain, pp. 62-67. G l gem ral account. 1886. Forbes. Transactions Illinois Department < >i-~< •] j- anm Injurious [nsectsof Kansas, pp. 7^ - ount 1892. Townbbnd, ( '. II. Tyi.ki:. Codling moth. BuL 5, New Mexico Station, March, 18 1893. Washburn. Bul. 25, Oregon Experiment Station, pp. 1-8. Record of original observations which form one of the most important and accurate contributions to the literature of the habits of this insect yet made. The egg figured fox the first time. 1893. Coquillbtt. Bul. o<». Division of Entomology of U. S. Department of Agriculture, pp. 30-33. - <>n life history, supposed enemies, and methods of combating tin- insect in California. 1893. Lintnbb. Ninth Report on Insects of New York, pp. 338-342. Detailed account <>i" the work of the Becond brood of larva- in New York: and a discussion ..f the prevalent ideas regarding the egg-laying habits of the insect 1893. Kii.ky. Bul. 23, Maryland Experiment station, pp. 71-77. Very g 1 general account of habits, remedies, and especially oftts enemi 1893. Lodkman Bul. 60, Cornell Experiment Station, pp. 266, 273-275. i.xp. riments t«. Bhow that usually two applications <>i" poisons arc all that arc nei <.r profitable in New York. 1894. smith. Entomological News, Vol. V. pp. 284-286. Records breeding experiments which indicate hut one brood of the insect a; New Brunswick. N. .1. 1894. Mablatt. [nseci Life Vol. VII. pp. 248-251. Evidence from various sources to show that insect is usually double brooded, 1894. SbMPBBS. Injurious Insect-, pp. ~>7-"> l .». Brief general Recount. 1894. Schilling. Der Praktische Ratgeber, vol. 9, pp. 1l , 1-1l , :; ; 133-135; 141-14: : 5. The best discussion of the insect from a practical and economical standpoint in the German literature, < >ne brood. 1894. Iv. Experiments \<iit<>mll. \. The codling moth. New Mexico Entomologist, No. 1, Apr. 21, 1894. Gabman, II. Spraying for codling moth. Bul. •">:;. Ky. A.gr. Expt. Sta., December, 18 1894. • es of the apple trees an«l its fruit. Nebraska State Horl »4 f p. 215. 1894. Wabhburm. Bul. 31, ( cperiment Station. 103 1895. Maklatt. Proceedings Entomological Society of Washington. VoL TIL pp. 22^-229. Suggests that Merri&m's life-zones may explain and determine the variation in and number of broods of the insect. 1895. Weed. Insects and insecticides. Second Edition, pp. S8-S9. Brief general account. 1895. Goethe. Bericht d. Kgl. Lehr. fur Obst. Wein, and Gartenbau, pp. 22-25. Records original observations .from breeding-cage experiment on the Qgg and on the habits of the young larvae, with illustrations and descriptions. First definite account of these phases of the insect to appear in any foreign literature. 1895. Adkix, Robert. The Entomologist, vol. 29, p. 2. Nat-feeding habits. 1895. Theobald, F. V. The Entomologist, vol. 29. p. 28. Xut-feeding habits. 1895. Adkix. South London Entomological Society. The Entomologist, vol. 28, p. 345. Nut-feeding habits. 1895. WasrwooD. South London Entomological Society. The Entomologist, vol. 28, p. 345. 1895. Garman, H. Experiments for checking apple rot and codling moth. Bull. 59. Ky. Agr. Expt. Sta., December, 1895. 1896. Smith. Economic Entomology, pp. 322-323. Good general account. 1896. Lodemax. The Spraying of Plants, pp. 252-255. Good general account. 1896. Slixgerlaxd. Michigan Fruit Grower, Vol. V, p. 8. Paper read before Mich. State Hort. Boc. Detailed account of original observations on oviposition and the habits of the young larvae, resulting in the discovery of some new and important economic facts. (The paper also appears in Rept. Mich. Hort. Soc. for 1896, and that portion oi it relating to the codling moth in the Rural New Yorker for Jan. 30, 1897. p. 67; and in the Proc. West. X. Y. Hort. Soc. for 1887, pp. 28-30. 1896. Bos. Tijdschrift over Plantenziekten. Vol. XII, pp. 52-74. Very good account compiled from the writings of Schilling and Goethe. 1896. Lolxsbury. Report Government Entomologist for Cape of Good Hope, for 1895, pp. 33-36. Brief account. 1897. \Valsixgham. Proceedings Zoological Society. London, p. 130. Concludes that Cydia iH the proper generic name. 1897. Smith. Garden and Forest, Vol. X, p. 334. Notes peculiar differences in habits of the insect in Xew Jersey, and especially at New Brunswick. N. J. 1897. Schoyex. Notes on insects of Norway and Sweden. Bui. 9, n. s., Div. Ent., U. S. Dept. ot Agr., p. 80. 1897. Slixgerlaxd, M. V. New facts about the codling moth. Garden and Forest. X. 468, Feb. 10, pp. 58-59. 1897. Card, F. W. Notes on the codling moth. Garden and Forest. Aug. 4, Vol. X. no. 493. 1897. Card. Garden and Forest, Vol. X, pp. 302-303. Detailed account of original Observations on egg laying and the habits of the young lar- vae in Nebraska. Eggs laid mostly on the leaves, and two broods, at least, indicated. 1897. Del Guercto. Bulletino della Soc. Ent. Italiana. pp. 12-17. Very good general account. 104 1897. Card. Bui. 51. Nebraska Experiment Station, 39 p. Inter it tons on the eggs and habits of the young larvae, with record pertinents against nil stages of the Insect. 1898. Slingebi wi». Tlir codling moth. Bui. Ml'. Cornell Univ. Agr. Expt Sta., pp. •_'<» flg The best account of this insect published. Gives summary of knowledge t<> ept. of Agr., p. 76. 1900. Aldbich. The codling moth. Bui. 21, Idaho Agr. Expt. Sta, 1901. Simpson. Report upon an investigation of the codling moth in Idaho in 1900. Bui. 30, n. b., Div. Ent, U. S. Dept. of Agr., p. 57. 1901. Mablatt. Important insecticides, directions for preparation and use. Fann- ers' Bui. L27, r. s. Dept of Agr. 1901. Simpson. <'im state Rural, No. 14. Published conclusion that there are tw<> generations at Boise, Idaho. 1902. < ilLLETTE Number of broods of the codling moth, as indicated by published -lata Ent News, XIII. p. L93. Oneof the most complete studies of the life history of any insect. Finds two genera- tions in Colorado. 1902. < mi. i. kith. Life history studies on the codling moth. Bui. 31, n. s.. Div. Ent, U. s. Dept. of Agr. 1902. Simpson. Report on codling moth. Investigations in the Northwest during 1901. Bui. 35, n.s., Div. Ent, I". S. Dept. of Agr. 29 pp. 5 plates. 1902. Garcia. Spraying orchards for the codling moth. Bui. 47, New Mexico Agr. Expt. sta. 1902. PlPER. Orchard enemies in the Pacific northwest. Farmers' Bui. L53, I . B I >ept of Agr. 1902. Cordley. The codling moth and late spraying in Oregon. Bui. 69, Oregon Agr. Expt. sta. Finds two generations *ud note- Important variations in life history. 1902. Sanderson. Eteporl of the Entomologist, L3th annual report of Delaware \-r. Expt Sta., p. 17-. 1902. SlingEBLAND. Trap lanterns or moth catchers. Bui. 202, Cornell Tniv. \ -r. Expt Sta. Results of extended experiments with trap lanterns. 1903. I The codling moth. Bui. 42, Montana Agr. Expt Sta, 1903. Simpson. Observations upon the life history of the codling moth. Bui. 40, n. v. Div, Ent, U, 8. Dept of Agr., p 105 1903. Washburn. A criticism upon certain codling moth observations. Ibid., p. 65. 1903. Aldrich. The codling moth. Bui. 36, Idaho Agr. Expt. Sta. 16 pp. Reports a partial third generation. 1903. Busck. Dimorphism in the codling moth. Proc. Ent. Soc. Wash., Vol. V, No. 3, p. 235. Describes new variety. 1903. Slingerland. American Fruit Culturist. The insects destructive to fruit, p. 177. A short general account. 1903. Ferxald, C. H. Bui. 32, U. S. Nat. Mus., p. 471. List of N. A. Lepidoptera, H. G. Dyar. 1903. Webster. The use of arsenate of lead as against the codling moth. Proc. 24th meeting Soc. for Promotion Agr., pp. 65-71. 1903. Sanderson. The codling moth. Bui. 59, Del. Agr. Expt. Sta. 1903. Simpson. The control of the codling moth. Farmers' Bui. 171, U. S. Dept. of Agr. 1903. Busck. Journal New York Entomological Society, Vol. XI, June. Restores generic name Carpocapsa. 6514— No. 41—03 8 O