ALBERT R. MANN LIBRARY New York State Colleges OF Agriculture and Home Economics AT Cornell University Cornell University Library The original of this book is in the Cornell University Library. There are no known copyright restrictions in the United States on the use of the text. http://www.archive.org/details/cu31924089521367 '■^•0^ «:';m ?"H 1>^ U. S. DEPAKTMBNT OF AGRICULTURE. SECTION. OF VEGETABLE PATHOLOGY. TREATMENT OF PLANT DISEASES. EXTRACT FROM THE .JOURNAL OF MYCOLOGY, VOL. 6, NO. I. (£//j. ^ ^ / ON THE EFFECTS OF CERTAIN FUNGICIDES UPON THE VITALITY OF SEEDS. A. A. Crozier. The influence of various chemicala upon the germination of seeds is but little understood. Many which have a fertilizing elfect when ap- plied in small amounts to the growing plant are injurious when a strong solution IS applied to the seed. There is evidence, on the other hand that many substances when applied to the seed will hasten germination and increase the vigor of the young plants. An account of some of these IS given by Prof. L. H. Bailey, in Bulletin 31 of the Michigan As- ricultural College. The following experiments were made with blue vitriol and copperas at the Iowa Experiment Station in 1889 : First, a rough test was made with a strong solution of blue vitriol, a teaspoonful in half a saucer of water. Corn was soaked in this twenty- four hours, and another lot soaked in pure water the same length of time, and both lots planted in soil in the greenhouse May 11. Exami- nation was made daily with the following results, the figures showing the number of plants which had appeared above the soil on the given dates, 100 seeds of each having been planted : ' I. — Blue vitriol upon corn. _ / Bate Twenty-four lioura. ^ Date. Twenty-four hours. Water. Blue vitriol. Water. Blue vitriol. May 16 57 96 97 97 98 98 98 98 5 45 52 56 71 77 79 80 May 24 98 98 98 98 98 98 99 99 85 86 86 86 87 87 87 17 25 18 26 19 27 20 28 21 29 22 30 23 31 The above table shows that the treatment with blue vitriol prevented the germination of some of the seeds and greatly retarded the germi- nation of most of the others. Many of the plants from the seeds treated with the blue vitriol came up feeble, with leaves which appeared as though scorched. On June 7, a part of these plants had become healthy, but they were as a whole much smaller than those from the 3 seed soaked in water only. The set treated with vitrio) contained twenty-eight plants, which were notably weak, and the other set but three weak plants. The next trial was with a solution of 10 gallons of water containing 5 pounds of blue vitriol (see Circular 5, of Sect. Veg. Path. tl. S. Dept. Ag., p. 5). The seeds were placed in the solutions on May 28, and allowed to remain for three different periods before planting. Exami- nations were made at the dates indicated, the figures showing the number of plants which had appeared above the soil from time to time. One hundred seeds were planted in each case as before. II. — Blue vitriol upon corn. Ten minutes. rive hours. Twenty-four hours. Date. Water. Blue vitriol. Water. Blue vitriol. Water. Blue vitriol. 10 -B7 81 91 95 95 95 S 41 63 85 87 89 92 20 75 91 93 93 93 7 41 72 85 87 91 2 40 77 87 89 91 93 6 20 7 60 8 75 9 70 XO 88 11 93 Here a general retarding effect of the blue vitriol is visible, even when the application was made for the shortest time. The exceptions which appear are not sufEcient to disturb the general result. There was also an enfeebling effect upon the young plants. On June 8 there were in the lot from seed which were soaked in water for ten minutes 6 feeble plants, and in that treated with vitriol for the same time, 23 ; in the lot treated with water five hours, 12 ; in that with vitriol, 19 ; in the lot treated with water twenty-four hours, 4 ; in that with vitriol, 22 ; making a total from 300 seeds soaked in water of 22 feeble plants, and from the same number soaked in blue vitriol, of 64. The next table shows the results of the same solution upon wheat, the dates and conditions being the same as above. III. — Blue vitriol upon wheat. Ten minotes. Five hours. Twenty-four hours. Date. Water. Blue vitriol. Water. Blue vitriol. Water. Blue vitriol. 77 81 81 82 83 83 85 46 55 58 62 74 Is 80 60 77 78 82 85 85 85 23 40 42 43 45 45 48 45 82 86 91 92 92 93 Q > 2 ! 10 8 16 9 23 10 29 11 84 87 It will be noticed from the above table that the wheat germinated much more quickly than the corn, and that the injurious effect of the blue vitriol was somewhat greater. A more severe test was made with the same solution of blue vitriol (5 pounds to 10 gallons) upon the same sample of wheat by allowing about a pint of the seed to remaiiuitt-thfi^olution for thirty-nine hours, and the same amount in water for an equal length of time. At the end of that time the water was turned off, a part of the seeds of each lot kept damp by blotting paper, and the remainder planted. Nearly all the seeds which had been in water grew well, but none of those which had been in the solution of blue vitriol. The next trial was of a solution of copperas or green vitriol upon corn. Copperas is used as a fertilizer, as a fungicide, and as an insecti- cide. Griffeth in his treatise on manures (London, 1889) after treating extensively of its use as a fertilizer, mentions its value as a fungicide, and states (page 302) that all fungous diseases of wheat may be destroyed by a top dressing of 50 pounds of copperas per acre, or by soaking the seed in a 1 per cent, solution. In Bulletin 5 of the Iowa experiment station, on page 164, reference is made to the use of copperas as a remedy for cut-worms, the amount recommended being a little over 1 pound for a bushel of seed, with water sufficient to cover the grain. This strength was taken for the trial, comparison being made with a much stronger solution, and also with pure water. The trial was made in duplicate, one set in the green-house, the other in the open ground, the other conditions being the same. The seed was soaked in each case twenty-four hours, and planted May 17, 100 kernels in a place as in the other tests. The examination was made daily, and, as in the other cases, as nearly as practicable at the same hour, usually at 6 a. m. The record begins on the day upon which the first plants appeared above ground. IV. — Copperas upon corn. Date. (a) In the green-hoase. ■Water. Copperas, 1 poand per bushel. Copperas veiy strong. (6) In the open ground. Water. Copperas, 1 pound per bushel. Copperas very strong. May 24 May 25. May 26 May 27. May 28. May 29. May 30. 1 20 59 73 74 79 79 A comparison of Tables IV with Tables I and II is sufficient to show that green vitriol (copperas) has nearly as injurious an effect upon the seed as blue vitriol. There was no scorching of the leaves noticeable, however, resulting from treatment with copperas, even with the strong- est solution. treatment of black-rot, brown-rot, downy mildew, powdery mildew, and anthracnose of the grape; pear scab and leaf-blight, and apple powdery mildew. By B. T. Galloway. black-rot.* The experiments of the past two years have demonstrated beyond question the possibility of cheaply and effectively preventing this dis- ease. Many things, however, in connection with its treatment remain to be discovered, so that rules now laid down will probably have to be modified, as future work gives us a better insight into the nature of the disease and the effects of different fungicides upon it. In the light of our present knowledge we would suggest the following lines of treat- ment, from which we will leave our readers to make their own selec- tions, since there is little choice, so far as the actual value of the rem edies are concerned. I. After pruning, collect and burn all the trimmings, also as many of the old berries and leaves as possible; the object of this is to destroy the fungous spores which are known to pass the winter in these parts. This accomplished, watch the vines carefully, and as the leaves begin to unfold apply the Bordeaux mixture, formula 6, taking care to have it reach all parts of the vine above ground. About the time the flowers are opening make a second application of the same formula, this time giving particular attention to the green parts. A third spray- ing should be made twelve or fifteen days later, a fourth after the lapse of a similar period, and so on until the berries begin to color. A line of treatment, such as the foregoing, will necessitate six or seven spray- ings, and the total cost of the same will probably range from $5.50 to $7 per acre, or practically 1 cent per vine. II. Treat the vines exactly as in I, excepting the first application, which may be omitted entirely, the first spraying being the one made when the flowers are opening. It is not out of place to say here that in no case should the first spraying be postponed later than the last-men- tioned period. This treatment will, of course, cost less than I, but whether it will pay to omit the first spraying is one of the questions not yet determined. III. Treat the same as I, but after the third application abandon the 'Lceetadia Bidwellii, (Sacc.) V. E. Bordeaux mixture and substitute the ammoniacal solution of copper carbonate. It is very likely that this treatment will prove as effectual as I ; at the same time the cost will be less, and the troublesome spotting of the fruit, which always results from the use of the Bordeaux mixture, will be avoided. IV. Substitute the ammoniacal copper carbonate for the Bordeaux mixture, making the first spraying when the flowers are opening and the others the same as in I. Former experiments have led us to believe that in ordinary seasons this solution will prove as effective as the Bordeaux mixture, and its advantages over the latter are (a) ease of preparation and application, (6) cheapness, and (o) its property of not spotting the fruit. Those desiring to make further trials should test the effect of spray- ing the vines in spring, before vegetation starts, with the simple solu- tion of copper sulphate or Bordeaux mixture, formula a. It is claimed by some that this early treatment has resulted in much good, but on the other hand there are those who have derived no benefit whatever from it. The question is one to be settled by careful experiments. For fur- ther remarks on this subject, see Notes on Fungicides. BROWN-EOT AND DOWNY MILDEW.* These diseases, which are caused by the same fungus, occur in nearly all sections where black-rot prevails, and experience has shown that one treatment will answer for all. In the great grape-growing region of northern Ohio and central and eastern New York, where the downy mildew is the principal enemy, the ammoniacal copper carbonate so- lution will prove an effectual preventive. It should be applied thor- oughly to all the green parts of the vine, taking care to taake the first application before any signs of mildew have appeared — say, soon after the berries are well set. The importance of early treatment can not be too strongly urged. In all cases it mast be remembered that these treat- ments are preventive, and being such, it is sheer folly to wait until the enemy appears before beginning the fight. POWDEET MILDEW.t It is only in certain parts of the South and along the Pacific coast that this fungus causes any serious damage. In California it has long been the bane of the grape-grower, and this is strange, considering the fact that it is one of the easiest diseases to combat. It succumbs readily to sulphur either in the form of the flowers of sulphur or solutions of the sulphide. In applying the sulphur, bellows should be used, and the first ap- plications should be made ten or twelve days before the flowers open, the second when in full bloom, and a third three weeks or a month later if the disease seems to be on the increase. The best results are obtained when the applications are made with the thermometer ranging "Peronospora vitioola, DBy. t Undnwla ampelopsidia, Pk. 8 from 80 to 100° P, In this temperature fames are given off, which quickly destroy the fungus. We have obtained excellent results in treating this disease with a solution made by dissolving half an ounce of potassium sulphide to the gallon of water. This preparation is cheap and can be quickly and effectually applied with any of the well known spraying pumps. The greatest care should be exercised in making the second spraying, which, by the way, should be at the same time as that mentioned for the flowers of sulphur, in order to protect the blossoms from the fun- gus. ANTHRACNOSE.* This is one of the most difficult of all the grape diseases to combat; in fact we must admit that so far no reliable means of preventing it are known. We can only suggest, therefore, such lines of treatment as have given the best results, hoping that future investigations may throw more light on the subject. In early spring, before the buds swell, remove, so far as possible, the wood showing the scars made by the fungus, and then treat the vines with a satura,ted solution (20 per cent, at 20° 0.) of iron sulphate. The French apply this by means of mops made of rags, attached to short handles. This is rather slow and awkward work, and -we prefer to do it with a spraying machine. As soon as vegetation starts watch the vines carefully, and at the first appearance of the disease apply with a sulphuring bellows a powder made of equal parts of flowers of sulphur and slaked lime. If this does not check the malady, try the sulphur alone. PEAR SCABt AND LEAF-BLIGHT.ij: Excepting the well known fire blight these diseases are the worst enemies of the pear. They are especially prevalent in New Jersey, Delaware, and adjoining States, frequently causing the loss of entire crops of fruit and thousands of seedlings. The seedlings are especially subject to leaf-blight, but are hardly ever, so far as we know, seriously injured by scab. As the two diseases, however, are usually associated on large trees, and as we have used the Bordeaux mixture successfully on the seedlings, we would suggest that it be adopted for all and ap' plied as follows: Seedlings. — Make flve applications, the first when the leaves are one- quarter grown, others at intervals of ten days until the trees are budded. Large trees. — Spray five times ; first when the fruit is the size of peas, and thereafter at intervals of twelve or fifteen days. For applying the mixture to trees less than 12 feet high, and especi- ally to seedlings in the nursery, the knapsack pumps provided with the improved Vermorel lance and nozzle will answer. * Sphaceloma ampeUnnm, DBy. ^Fusicladium dendriticum. Fckl. t EntomoBjaonum maoulatum, L6v. Where the trees are large and in considerable numbers it will pay to get a strong force-pump, mount it ou a barrel, and place the whole in a wagon or cart to bo moved about at pleasure. In all cases, however, it will be necessary to use the Vermorel nozzle, as it is the only nozzle of value that will not clog; it can readily be attached to almost any force-pump, and will be found to be a very effective piece of machinery. The total cost of a course of treatment such as is outlined above, including labor in preparing and applying the remedies, will be for nursery stock about $3 per 1,000 trees. For large bearing trees the cost will run from 6 to 12 cents per tree. In case the Bordeaux mix- ture shows on the fruit at the time of harvesting it can easily be re- moved by washing in water. In addition to the foregoing it would be well to rake the old leaves and fruit together in the fall and burn them, as in this way thousands of the reproductive bodies will be destroyed. In regions where the scab alone prevails the treatment recommended for apple scab might be tested. POWDERY MILDEW OF THE APPLE.* Powdery mildew is especially destructive to seedlings in the nursery, attacking them soon after the leaves unfold and continuing throughout the growing season, making it impossible to bud them with any degree of success. When the leaves are about one-third grown begin the treatment by spraying with the ammoniacal solution. In twelve days make a second application of this solution and continue at similar intervals until six or seven sprayings have been made. The applications are best made with the knapsack form of sprayer provided with the Eddy chamber nozzle. The spray of the Vermorel nozzle is too large for this work, but the Eddy chamber can be easily attached to the lance of the former at a cost of 75 cents. The total cost of such a treatment as outlined above need not exceed 10 cents per 1,000 trees. .what to do for peach yellows. By Erwin p. Smith. A series of experiments with fertilizers was begun in 1889, and will be continued until complete and definite results are reached. These experiments are in twelve orchards in different localities and on a variety of soils, embracing a total of about 40 acres, with as many more for comparison. The results last year were not of such a nature as to warrant any affirmative conclusion or any general recommendation. * Podoaphcvra oxyacantha (DC), DBy. 10 For the present, at least, I can only indorse the Michigan practice, which is to dig out and destroy every affected tree as soon as it is dis- covered. In localities where this method has been practiced with some uni- formity they still grow peaches successfully. In the vicinity of Benton Harbor, Mich., where all the orchards were ruined between the years 1870 and 1880, there are now many fine young orchards, and the yellows has almost disappeared. In the summer of 1889, in company with Mr. Eufus H. Brunson, a former yellows commissioner, I visited many small orchards in different parts of the townships of Benton and St. Joseph, the former chief seat of the disease, and examined nearly 30,000 trtes, finding only about fifty cases, nearly one-half of which were in one orchard. More than four-fifths of these trees were less than six years old. Many of the older ones, and most of those which I examined, were in fruit, and the earliest varieties were just coming into market, July 24. With a few exceptions, the only extensive orchards were young trees not yet in bearing, the earlier plantings having been numerous, but in a small and tentative way, no single individual caring to risk many thousand trees. Now, however, large orchards are being set. Whether the present immunity will con- tinue is a matter of great interest. If there is any real basis for the belief that the disease may be imported, it certainly will not, for many of the younger trees were procured from infected districts in the East. All fear of the disease seems to have died out, and with it most of the former vigilance. At South Haven, Mich., where the "rooting out" process was first practiced extensively, and where it is yet in full vigor, they have grown peaches continuously from the start (1852), and there are many old or- chards, some of which have stood for twenty-five years. In that locality I examined many representative orchards, and found only a very few cases of yellows. Sometimes, as at St. Joseph, it was a day's work to find a single case. Most orchards of any size do, however, lose some trees each year, their places being filled by trees from the nursery. The South Haven growers, many of whom I have met, no longer fear the disease. They are unanimous in the opinion that the only proper thing is to dig out and burn. This plan they have followed very generally for the past ten years, during which time the disease has not prevailed seriously. Previous to that date many orchards were ruined, the dis- ease having appeared first in 1869. Until we have a full knowledge of the aetiology of this disease, no better plan can be suggested. Affected trees are always worthless, and the sooner they are converted into stove-wood the sooner new, healthy trees can be grown in their places. Big out, then, and burn, and dp it promptly. 11 TREATMENT OF MILDEWS UPON PLANTS UNDER GLASS, By S. T. Maynaed. In Bulletin No. 4, Massachusetts Experiment Station, April, 1889, ex- periments were reported upon the causes and remedies for mildews upon plants under glass. Below we give a brief summary of the results. KOSE MILDEW.* Long experience in growing the rose has led many to believe that the rose mildew is brought on by various conditions that weaken the vigor of the leaf, such as want of an abundance of plant food in a proper condition, unhealthy condition of the soil, often resulting from improper drainage, irregular or overwatering, or too sudden changes of tempera- ture, especially after the plants have been forced at a high temperature. The successful rose grower therefore, is one who, by constant care and good judgment, always provides against any or all of the above causes. BEMEDY, A sure and safe remedy, with proper precautions, was found in evapo- rated sulphur. In the use of this remedy a small kerosene stove with a thin iron kettle was used, and the sulphur kept boiling two or three hours thrice each week when the house was closed. Precaution. — The only precaution needed is that the apparatus be placed so that there shall be no danger of its getting upset, and that only heat enough be applied to boil the sulphur, for, if by any accident the sulphur should catch on fire, it would destroy all the plants in the house very quickly. Suggestion. — It has been suggested that if the pipes are painted with linseed-oil and sulphur two or three times each year, similar good results would follow. It has long been the practice to paint greenhouse pipes ■with a mixture of lime and sulphur, but the results have not always been satisfactory, and the above suggestion may be opeu to the same objection, although we know of no carefully recorded experiments in the use of linseed-oil and sulphur paint. LETTUCE MILBEW.t When grown at a temperature above 40° F. at night, 55° F. in cloudy, and 70° F. in sunny days, lettuce under glass is often ren- dered unprofitable by the attack of this disease which causes the lower leaves to decay, and often the whole plant to die quickly. Other con- ditions may in a measure aid in bringing on the disease ; for instance, * Sph(Brotheca pannosa, (Wallr.) L^v. t Peronoapora gangliformis, Berk. 12 anything that may cause a weak leaf-action of the plant, too much water in the soil, and too much moisture in the house, especially during the night. EBMBDY. Evaporated sulphur proved beneficial, but not wholly preventive, in fact, only preventive conditions were found satisfactory. These condi- tions are: 1. A lower temperature at night than during the day, i. e., ranging from 350 P. to 450 F. at night to 50° F. to 70° F. during the day. In sunny weather the tempei'ature may run 10° to 15° higher than on cloudy days. 2. Perfect drainage of the soil. 3. A house naturally dry, light, and airy. 4. An abundance of plant-food in a light porous soil. Should the plants not start into a vigorous growth soon after trans- planting, the application of flue ground bone, one-half pound to a square yard, and 2 ounces of nitrate of soda to the same space, will give remark- able results. Suggestion. — While it is possible by close and constant attention to provide conditions for the successful growth of both the rose and lettuce under glass, such care and attention adds very materially to the cost of the products, and some means should be devised to destroy the germs of these diseases. This may possibly be found in fungicides used in the houses, before the plants are started or by their application to the soil and growing crops while in a young state. Amhekst Agricultural College, Amherst, Mass. TREATMENT OF CRANBERRY SCALD AND CRANBERRY GALL- FUNGUS. By Byron D. Halstbd. It has been determined by a thorough canvass that a large fraction of the cranberry crop is destroyed by the scald, sometimes called " rot." The loss sometimes reaches as high as 65 per cent., and in many places it has rendered the growing of cranberries a profitless industry. A fungus is closely associated with this scald, and in no case has a soft berry been examined microscopically without the same fungus being present. The leaves, vines, and roots also of the plants bearing scalded berries, abound in the same fungus. In general structure, hab- its, and behavior, the fungus of the cranberry scald is closely related to the one causing the black-rot of the grape. As yet no fungicides have been tested upon the scald, but from its relationship to the black- rot of the grape it is only reasonable to infer that the same treatment 13 might be efficacious. In view of the fact that the cranberry has small smooth thick leaves it is possible that the mixtures employed for the grape could be used with greater strength upon the former. However, a beginning can be made with the ammoniacal copper carbonate solution, directions for the preparation of which will be found elsewhere in this Journal. The amount of this solution to be applied per acre can not be stated because it will vary with the rankness of the vines. Apply for the first time as soon as the spring flooding is past, and again just before the blossoms unfold. The third application should be in midsummer followed by two others at intervals of two weeks. This makes five spray ings in all. The instruments to be used will depend much upon circum stances. If the owner applies Paris green or London purple for the in sect enemies of the cranberry, namely, the tip worm, vine worm, etc. then the remedy for the scald can be applied with the same pump. There is much Xo be done in improving the sanitary conditions, if that term may be used, of the bogs. It is important to have perfect control of the water supply, and during the growing season, while keep- ing the bog moist enough for the plants, have the ditches deep and free flowing that stagnant water can be kept from the roots of the plants. Doubtless much depends upon having the soil of the bog in the best condition for the healthy growl h of the plants. Where the peat is sonr and soaked with standing water the best conditions obtain for the scald. It may be that proper drainage, water control, and sanding will bring the necessary conditions for healthy plants, and the old plants may outgrow the trouble with the aid, in the meantime, oif the remedy proposed. The best thing to do will be to try and see, upon a small area, provided the practical pecuniary test of possible profit prompts the owner. Some bogs are so poorly adapted for this peculiar industry that it will not pay to spend money upon them, others, never- theless, merit much more attention than they receive. THE GALL-FUNGUS. This appears to be confined to a single bog in New Jersey, but in that one it is disastrous. Several closely related shore plants as azalea, sheep laurel, lambkill, white alder, leather leaf, huckleberry, and tea berry or winter green, are attacked by the same fungus {Synchytrium Vaocinii, Thomas). The disease is spread by the water in the spring floods and does not pass readily through the air. There is some danger, however, of the pest spreading to other bogs and therefore if this bog was destroyed by fire, together with the infested shore plants there might be hope for a speedy end to the trouble. The matter is so local that it does not merit further treatment here. The two diseases of the cranberry herein briefly treated are consid- ered at length, with several engravings, in Bulletin 64 of the New Jersey Experiment Station. Rutgers College, New Brunswick, N. J. 14 treatment of apple scab By E. S. Gopf. Eecent experiments indicate that apple scab {Fusicladium dendritieum, Fckl.) may be almost entirely prevented by the application of certain liquid preparations, in the form of a spray, that, while harmless to the foliage and fruit of the tree, are destructive to the fungus which causes the disease. Yarious substances have been found to be more or less beneficial, but at the present state of our knowledge, a solution of copper carbonate in ammonia largely diluted with water is to be most strongly recommended. Experiments conducted, the past season, in the orchard of Mr. A. L. Hatch, of Ithaca, Wis., with this preparation proved so far satisfactory that Mr. Hatch has decided to apply the treatment to his entire orchard of about 25 acres the coming season, as a means of increasing the income from his apple trees. DIRECTIONS FOE PREPARING AND APPLYING THIS FUNGICIDE. The copper carbonate and the ammonia may be procured through almost any retail druggist. As the former is not always kept in stock it would be well to order it some days before it is desired for use. The copper carbonate should be of the "precipitated" form, and is worth at retail about 65 cents per pound. The ammonia should be of a strength of 22° Baum6, and should be procured in a glass or earthen vessel and kept tightly corked, preferably with a rubber cork. Four ounces of the copper carbonate and 1 gallon of ammonia will be sufiicient to give about fifty large or seventy-five medium-sized trees one thorough spraying. As four or five treatments will be needed for a thorough application of the remedy the amount of the materials re- quired for any given orchard may be readily computed. The best formula that can be given in the present state of our knowl- edge is to dissolve one ounce of the copper carbonate in one quart of ammonia, and dilute this, when ready to commence the application, with 25 gallons of water. ■WHEN TO MAKE THE APPLICATIONS. In the experiments made the past season in Mr. Hatch's orchard the first application was made after the petals of the flowers had fallen, and when the young apples were slightly larger than peas. But it is the opinion of Mr. Hatch and myself that one spraying before the flowers had opened would have proved beneficial. I would recommend, there- fore, one treatment just before the flowers open, a second after the petals have entirely fallen, and others at intervals of two or three weeks until midsummer, or after, if the latter part of summer should be wet. 15 APPARATUS FOR SPRAYING. For applying the liquid to the trees, a force-pump, to which is attached a few feet of hose, fitted at the end with a spraying nozzle, will be needed. Excellent pumps are now made by the larger manufacturers expressly for spraying purposes, fitted with all necessary attachments, and cost- ing $10 and upwards. Smaller pumps, which would answer fairly well for a few trees, may be had at from $2 to $10 each. The same pump which is used for treating tiie trees for the apple scab may of course be used for applying poisons for the codling moth and other insects. Unfortunately it will not be prudent to add the copper carbonate solution to the same water that is used in applying Paris green or London purple, as the ammonia renders the arsenic more or less soluble and thus the latter would be liable to injure the foliage. But if applied a few hours in advance of the water containing the arsenites, no harm can result from this source. SUGGESTIONS FOR FURTHER EXPERIMENTS. The time at which the applications should commence, the number that should be made, and the amount of copper carbonate to be used to accomplish the greatest benefit at the least cost, remain to be settled by experiment. The most practical remedy for the apple scab must be one that may be applied in the same water with Paris green or London purple with- out thereby endangering the foliage. It is the opinion of our station chemist, Dr. Babcock, that not only the ammoniacal copper carbonate, but the sodium hyposulphite and the sulphides of lime and potash, all tend to render the arsenic of Paris green and London purple soluble, and hence can not be wisely used in connection with these poisons. The copper carbonate, however, which in the ammoniacal solution is the beneficial agent in preventing the apple scab, does not have this effect when used without the ammonia. The question therefore arises, is the ammonia solvent necessary ? I have recently made some tests with a sample of commercial precipi- tated copper carbonate, and find that its state of division is such that it remains suspended in water rather better than Paris green, and so may be applied by any apparatus that successfully distributes the latter. It apparently adheres to the foliage nearly or quite as well, when applied in simple suspension, as in the diluted ammoniacal solu- tion. I recommend, therefore, that those who spray their apple trees for the prevention of injury from the codling moth, make the experiment in a portion of the orchard of adding the. precipitated copper carbon- ate to the water, at the rate of an ounce to twenty-five gallons. ISo harm to the foliage can result from this measure, while we have every reason to expect that much benefit will accrue in the prevention of the apple scab. University op Wisconsin, Madison, Wis. 16 the copper salts as fungicides. By p. D. Chestee. In order to make an intelligent comparison between the several well known fungicides containing copper, it is important to understand what salts of copper occur in each and in what relative proportions. This in turn involves some inquiry into the chemical reactions which take place in their preparation and during their stay upon the vine. For much valuable assistance in the preparation of these notes I am indebted to Prof. 0. L. Penny, the Chemist of this Station. THE BOEDEATJX MIXTTJEE. Formula. — Copper sulphate, 6 pounds; lime, 6 pounds; water, 22 gallons. In the addition of milk of lime to a solution of copper sul- phate, the lime in solution precipitates the copper as cupric hydroxide, forming at the same time a slightly soluuble sulphate of lime. These two salts, together with an excess of lime, remain in suspension in the Bordeaux mixture. The reaction is simple: CuSO^, SHsO + CaO.HsO = Cu (OH)j + CaSO< + .5H,0. From this formula a simple calculation shows that to precipitate the 6 pounds of copper sulphate, there would be required 1.34 pounds of lime (CaO), which would in turn produce 2.34 pounds of cupric hy- droxide. The weight of lime to be used should be considerably increased above this amount, owing to its impure character as ordinarily purchased, but it is likely that 3 or 4 pounds of commercial lime will suffice to satisfy this reaction. The 22 gallons of water is capable of dissolving approximately .235 pounds of lime, an amount sufficient to precipitate practically 1 pound of the copper sulphate. But since this quantity of lime is immediately thrown down as a nearly insoluble sulphate, the water is free to dis- solve another portion of lime, which in turn precipitates another portion of the copper, until all of the copper is thrown down. It is found that this complete precipitation of the copper takes place quickly, or by the time the matter in suspension has fully settled, leaving a clear super- natant liquid, which does not react for copper ; hence a long standing of the Bordeaux mixture before use is hardly necessary. In drying upon the plant the cupric hydroxide in the Bordeaux mix- ture undergoes no change, hence it is probably this salt of copper which is the active principle. 17 EAU CELESTE. Formula. — Copper sulphate, 1 pound; strong ammonia, IJ pints; water, 22 gallons. In the addition of ammonia water to a solution of normal copper sul- phate, the copper is precipitated as a basic sulphate, forming at the same time ammonic sulphate, which remains in solution. With an ex- cess of ammonia, the basic copper sulphate dissolves to a blue fluid foi'ming the ammonio-copper sulphate (GUSO4, 4NH3, U^O). In drying upon the plant the ammonio-copper sulphate gradually loses its ammonia and is reconverted into the basic copper sulphate. The following are the probable reactions : (1) 3CUSO4, 5HaO + 4NH4HO = CUSO4 2Cu(OH)3 + 2(NH4)s SO^ + ISHjO Normal cop- Basic copper per sulphate sulphate. (2) CnSOi, 2Cii(OH;3 + 2(NH4)2SO, + 8NH4HO = 3(dnS04, 4NH.„ HgO) + In excess. Ammonium copper 9HaO sulphate. (3) In drying upon the vine. 3(CuS04, 4NH3, H,0) -f mo = CnSOi, 2Cu(0H)3 + 2(NH4)iiS04 + 8NH» To satisfy the reactions (1) and (2), the one pound of copper sulphate would require .439 pounds of ammonia gas (NH3) ; or 1.66 pints of the stronger water of ammonia of the TJ. S. Pharmacopoeia (sp. gr. 0.900 at 15" O.), producing in turn .47 pounds of the basic copper sulphate. MOBIPIED EAU CELESTE. Formula.— SalphSLte of copper, 2 pounds; carbonate of soda, 2J pounds ; strong ammonia, IJ pints ; water, 22 gallons. In the addition of a solution of sodic carbonate to a solution of copper carbonate the copper is precipitated as a basic carbonate, forming at the same time a soluble sulphate of soda. Upon the addition of ammonia the basic carbonate dissolves to a blue fluid forming the ammonio-copper carbonate (OuOOs, 2NH3), and the amnionio-cnpric hydroxide. (30u( JH)2, 4NH3, SHzO.) In drying upon the plant both of these salts gradually lose their ammonia, and are converted into the basic carbonate and into the cupric hydroxide. The following are the probable reactions : f n 12 (CUSO4, 5ff 0) -f 12 (Na.CO„ lOH.O) = e rCuCOa. Cu(OH)„ H,0] + ^ ' Basic carbonate of copper. 12Na3S04-|-6C02-l-168HsO (2) 6[CuC03, CuC(OH).]+20NH4HO=6(CuCO3,2NH3)-f ^ To dissolve. Ammonio-copper carbonate. 2 r3Cu(OH)a, 4NH3, 3HaO] -f 14HijO. Aminonio-cupric hy- droxide. 22162 P D 2 18 (3) In drjing upon the plant. 6(CaC03, 2NHri)+6HiO= 3[CaC03, Cn(OH)2] +3(NH4)3C03+6NH, Basic carbonate of copper. 2[30u(OH)2, 4NH3, 3Hsa]=6Cu(OH)s+8NH3+6H,0. From the above formula it is found that to satisfy the reaction, the two pounds of copper sulphate will require 2.3 pounds of crystallized carbonate of soda, which will eventually produce .44 pounds of basic carbonate of copper and .38 pounds of the cupric hydroxide, or a total of .82 pounds of the mixed salts. AMMONIACAL COPPER OABBONATE. Formula. — Copper carbonate, 3 ounces; strong ammonia, 1 quart; water, 22 gallons. In the preparation of this solution, the chemistry is the same as that given under modified eau celeste and the reactions are given in for- mulae (2) and (3). Upon the same basis as before, 3 ounces of copper carbonate will yield 1.5 ounces of basic carbonate and 1.32 ounces of cupric hydroxide, or a total of 2.82 ounces. The difference between the modified eau celeste and the ammoniated copper carbonate consists in the presence of sodium sulphate in the former material, and its absence in the latter. Whether this sodium sulphate will be at all harmful to foliage is a ques- tion to be decided by experiment, and the writer would advise that this question be tested. The cost of the copper carbonate in the modified eau celeste is approximately 20 cents per pound," while the cost of the commercial carbonate, is, according to present quotations, 65 cents per pound. Furthermore it is seen from the following table that the cost of the basic salts of copper deposited upon the plant, is, in the modified eau celeste, 29 cents per pound, and in the ammoniacal copper carbon- ate 94 cents per pound ; a difference worthy of serious consideration. In the use of both the modified eau celeste and the ammoniacal cop- per carbonate there is not produced continually a basic carbonate of copper, but a mixture of the basic carbonate, and the hydroxide. Would it not therefore be well to try the pure basic carbonate either by pre- cipitating the copper with sodium carbonate, and applying it in suspen- sion as the hydroxide is applied in the Bordeaux mixture or by dissolv- ing this precipitate in ammonium carbonate ? By the former method, using 2 pounds of copper sulphate, and 2J pounds of sodium carbon- ate, we would have an extremely cheap and perhaps effective fungicide. The following table has been constructed that the facts contained in this paper might be presented in a condensed form. The writer in conclusion would particularly recommend that the rela- tive value of the hydroxide, the basic sulphate, and the basic carbonate 19 be tested by the application of materials containing equal weights of these salts per unit of water. Name of fangicide. Form of salts when diy upon the plant. Weight of fore- going salts per 22 gallons. Weight of original copper salt to make 1 pound of salt when dry on plant. *Cost of fungi- cides per 22 gallons. Cost of 1 pound of copper salt when dry on plant. Bordeaux mixture Eau celeste Cupric hydroxide, Cu{0H)2 Basic copper sulphate, Cu SO4, 2Cu(0H)!. Basic copper carbonate, Ca CDs, Cti(OH)j, and Cnprio hydrox- ide, Cu(0H)2. Basic copper carbonate, On CO3, Cn(0H)a, and Cupric hydrox- ide, Ca(0H)2. Ptmnds. 2.34 .47 .82 Ouncee. 2.82 Pounds. 2.5 2.13 2.44 1.06 Cents. 34.25 21.25 24.37 16.6 ^0. 146 .452 Modified ean celeste Ammoniaoal copper car- bonate. .297 .942 • Wholesale cost of materials from which calculations in the last two columns of the above table were made: Copper sulphate, 5§ cents per pound ; sal soda, li cents per pound; strong ammonia (26°), 7 cents per pound ; copper carbonate precipitated from copper sulphate by sal soda, 13.87 cents per pound. Delaware College, Newark, Del. notes on fungicides and a new spraying pump. By B. T. Galloway. In connection with the papers found elsewhere in the Journal, it would seem proper to say something in regard to the preparation of fungicides, particularly those recommended for use. The manner of preparing most of these, however, has been so fully described in former publications that we deem it unnecessary to repeat the descriptions here. We will say, in passing, that the circulars— Nos. 5 and 6 of the Section of Vegetable Pathology— containing this information will be forwarded to all those desiring to consult them. Aside from the old and well established preventives and remedies, there are several new ones which we think it would be well to call at- tention to in order that they may be more fully tested. The first of these is a solution of copper acetate or verdigris, which was mentioned in Volume 5, Number IV, of the Journal. It is prepared as follows : Dissolve 3 pounds of powdered verdigris in 6 to 8 gallons of water and after standing for twenty-four hours dilute to 22 gallons. If de- sired the amount of verdigris may be increased to 4 pounds without in- jury to the plants. This preparation being comparatively cheap and easily prepared, it would be well to test it for downy mildew and black-rot of the grape, 20 making the applications as described for Bordeaux mixture and the other well-known preparations. Another preparation which might be tried for downy mildew is made as follows : Dissolve 5 pounds of alum in 3 or 4 gallons of boiling water, and then pour this solution into a half barrel or tub containing sufficient cold water to make 15 gallons. In another vessel dissolve 42 pounds of calcium chloride in 3 gallons of cold water. Finally, pour the cal- cium chloride solution slowly into i^he alum preparation, stirring con- stantly to eifect a thorough mixing. When the two solutions are mixed there is formed aluminium chloride, potassium sulphate, and calcium sulphate. It is claimed that the fun- gicidal property lies in the first, while the calcium sulphate facilitates its adhesiveness. The potassium sulphate is, as every one knows, a fertilizer and as it is washed from the leaves it enriches the soil. In addition to what is said here the papers of Professor Goff and Professor Chester should be carefully consulted, fis they contain several new and important suggestions in regard to the preparation and ap- plication of fungicides. For the benefit of those having in mind the treatment of plant diseases the coming season, we quote below the usual prices of the various chemicals used in the preparation of fungicides. The quotations are for 100-pound lots. In smaller quantities the prices will range from one fifth to one- third higher, so that money will be saved if farmers and fruit-growers will club together in making their pur- chases. Such an arrangement will also save considerable in the way of transportation expenses. Copper carbonaite Copper sulphate Potassium sulphide Aqua ammonia (22 Beanm6) Sodium hyposulphite Copper acetate Per pound. $0.60 .08 .25 .08 .03 .30 Iron sulphate Flowers of sulphur . . Alum Calcium chloride Aluminium sulphate Lime per barrel Per pound. $0.02 .04 .03i .06 .05 2.00 NEW SPRAYING PUMP. Ever since the work of the Section was inaugurated there has been felt the need of a cheap, serviceable, and effective apparatus for spray- ing grapes and all the low-growing crops. Heretofore we have had to rely mainly upon machines imported from France; in fact, with but one exception, the only pumps that have given satisfaction in our vineyard work have been purchased abroad. The average fruitgrower can not afford to send to France for a machine that will cost him, laid down in this country, all the way from $18 to $25, nor can he pay $21 for a pump made here, notwithstanding the fact that it is a most excellent machine and costs almost the selling price to manufacture it. In short, a knap- 21 sack pump, be it ever so serviceable, at $21 or even $18, is entirely be- yond the reach of the average farmer, gardener, and fruit-grower. Con- sequently he has to rely upon inferior machines, and, as a result, his treatments are frequently unsuccessful for the simple reason that the remedies are not properly applied. We have had the matter of providing a cheap and serviceable knap- sack pump under consideration for some time, and can now positively announce that the machine will be on the market in a few weeks. The pumps will be made in two or three styles, and as there will be no pat- ent on them we hope manufacturers throughout the country will be able to oflfer them at about $12, thus placing them within the reach of all PREVENTION OF SMUT IN OATS AND OTHER CEREALS. By W. a. Kelleeman and W. T. SwiNaLE. The smuts of oats aud other plants are minute vegetable parasites. They appropriate for their use the nourishment which the infected plant prepared for its own development, aud in this way reduce its vitality or completely destroy the part attacked. The dark-colored powdery mass popularly called the smut is merely the mature fruit of the parasite, and consists of exceedingly minute reproductive bodies called spores. These, when subjected to proper conditions, germinate by sending out a slender tube upon which small sporidia appear. The smut arrives at maturity in case of oats when the latter are in bloom, and the spores, blown hither and thither, find their way into the flowers. The husks soon close over the young grain, and the spores which may have been thereby imprisoned remain dormant until the seed is planted in spring. The warmth and moisture cause the spores and the oats to germinate simultaneously. The slender tubes emitted by the spores now penetrate the delicate oat plants. Thereafter the smut plant grows concealed within its host until they both approach maturity. At this time the smut spores rapidly develop in the abor- tive head of oats and the black mass of smut becomes conspicuous. It is sometimes claimed that smut in the soil, or in manure applied to the soil, will infect the young oat plants. This is certainly not the usual mode of infection and it may be doubted whether it ever occurs. If the spores inclosed in the husks of the grain can be killed without injuring the seed, the smut can be perfectly prevented in the crop. This has usually been accomplished by soaking the seed in a solution of blue vitriol (copper sulphate). This process though destroying all or nearly all the smut, also injures the seed more or less. The hot- water method of Professor Jensen has proven thoroughly effectual in preventing smut and, besides, is not in the least injurious to the seed. In fact, both our own and Jensen's experiments show yields greater than would be expected from the mere prevention of the smut. We 22 therefore recommend this treatment, which consists simply in immers- ing the infected seed in scalding water (132° Fahr.) for not less than five nor more than fifteen minutes, and immediately thereafter cooling it quickly by immersing in cold water. In order to carry out this process satisfactorily when a large apiount of seed is to be treated, two large vessels must be provided. These can be large kettles hung over a fire, or large boilers on a cook-stove. One vessel is to contain heated water (about i 10° to 120° Fahr.) for the purpose of warming the seed preparatory to dipping into the second vessel. This second vessel is to contain water at a temperature of 132® to 135° F. Were not the seed warmed before dipping into the vessel of scalding water the temperature of the latter would be very much re- duced, perhaps below 130°, and then the treatment would not be effectual. The seed, a half a bushel or more at a time, is to be placed in a coarsely- woven basket having a lining of wire netting with meshes fine enough to prevent the egress of the grains, say, twelve to the inch. A heavy wire bushel-basket may be used, or a light iron frame made over which the wire netting may be stretched. A lid or cover must be provided for, otherwise a portion of the seed will escape upon immer- sion. A sack made of coarsely woven cloth might be used instead of the basket, but it is much less convenient. It is necessary that the basket admit the water freely and immediately upon its immersion, otherwise the treatment can not be expected to be effectual. An immer- sion of a few moments (less than a minute) will sufficiently warm the basket of seed, provided that it be lifted out then plunged in a time or two and shaken or revolved so that the water may come in contact with the grains. Then plunge it immediately into the second vessel, and ■ with similar motion bring every grain into immediate contact with the scalding water. The lifting and plunging should be continued at short intervals until the seed is removed. In this way every portion of the seed will be subjected to the action of the scalding water. Immediately after its removal dash cold water over it or plunge it into a vessel of cold water and then spread out to dry. Another portion can be treated similarly, aad so on till all of the seed has been disinfected. The important precaution to be taken is as follows: Maintain the proper temperature of the water (132° Fahr.), in no case allowing it to rise higher than 135° or to fall below 130°. This will not be difficult to do if a reliable thermometer is used and hot or cold water be dipped into the vessel as the falling or rising temperature demands. Immer- sion fifteen minutes will not then injure the seed, though no doubt in a less time it will be thoroughly disinfected. The seed can be treated any length of time before sowing. If it is to be stored it would be necessary to have it first thoroughly dried. If treated immediately before using it can be sowed broadcast when dried sufficiently to prevent adhesion of the grains, but for planting with the drill it would need perhaps to be more nearly dry. 23 The above outline of treatment is for oats, wheat, and rye. Professor Jensen has determined that barley must be previously soaked iu cold water eight hours, otherwise the smut is not prevented. It is to be remembered that this treatment if universal in any section of country will, besides preventing smut in the crop of the seasoHj also insure clean seed for use the following year. It has been established by actual count that the smut often destroys a very large percentage of the crop. When the smut was reported to be inconsiderable or even absent, we have determined that there may be 5 to 15 per cent, of the heads smutted. These are at harvest time usually overlooked because the smut has been blown away and the inconspicuous naked and clean stalk only remains. It might be added in this connection that it has been established recently that the smuts of barley and wheat, though much resembling that of oats, are really different species. Finally we may mention by way of suggestion for the benefit of others that farther experimentation is now being prosecuted, or about to be undertaken, having in view the determination of numerous points in connection with the application of fungicides for the prevention of smut. Among these are the following: A comparison of the efficacy under varying conditions of the hot-water treatment with other fungicides ; comparison as to increase of yield when this or any other fungicides are used; trial of the Jensen method with other plants besides oats and wheat, as barley, rye, grasses, millet, and maize; and the determination of the most favorable form of treatment, particularly with reference to the degree of temperature required, the duration of the immersion in hot water, and the mode of cooling. Kansas State Ageiculttjeal College, Manhattan, Kansas.