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NEW CITRUS CREATIONS OF THE DEPARTMENT OF 
 
 AGRICULTURE. 
 
 HERBERT J. WEBBER and WALTER T. SWINGLE, 
 
 Vegetable Puthohxjmd and Physiologiral Jnrestigations, 
 Bureau of Plant Industry. 
 
 [Reprint krom Yearbook of Department of Agricultckk for 1904.] 
 
 ^-^ 
 
uG 7 » 
 D.otO. 
 
 
 AUG 7 1907 
 
 AUG 7 
 AUd).r'D. 
 D. Of' D. 
 

 CONTENTS. 
 
 Page. 
 
 Introduction 221 
 
 Production of hardy citrus fruits 223 
 
 The citrange, a new group of citrus fruits ^ ^ 227 
 
 Ru.«k citrange 228 
 
 Willits citrange _. 229 
 
 How hardy is the citrange 231 
 
 Of what value is the citrange 234 
 
 The tangelo, a new group of loose-skinned citrus fruits 235 
 
 The Sampson tangelo 236 
 
 Uses of the tangelo 237 
 
 New tangerine oranges 238 
 
 The Weshart tangerine „ 238 
 
 The Trimble tangerine 238 
 
 General qualities of new tangerines 239 
 
 ILLUSTRATIONS. 
 
 PLATES. 
 
 Page. 
 
 Plate X. Branch of trifoliate orange 224 
 
 XI. Hybrid seedling of common orange (female parent) and trifoliate 
 
 orange (male parent) 228 
 
 XII. Fruits of Rusk citrange and trifoliate orange 228 
 
 XIII. Fruits of Rusk and Willits citranges, with trifoliate orange for com- 
 
 parison ^. 228 
 
 XIV. Seedling hybrids of trifoliate orange crossed with pollen of the 
 
 eoonnion orange 230 
 
 XV. Seedlings of citrus hybrids, showing relative vigor of true and false 
 
 hybrids 230 
 
 XVI. Willits citrange 230 
 
 X VII. Sampson tangelo 236 
 
 XVIII. Sampson tangelo, showing easily removable rind 236 
 
 XIX. Sampson tangelo and ordinary pomelo 236 
 
 XX. Weshart tangerine 238 
 
 XXI. Group of Weshart tangerines, with parent varieties 238 
 
 XXII. Trimble tangerine 238 
 
 TEXT FIGURES. 
 
 Fig. 12. Three seedlings grown from a single seed of a hy])rid 226 
 
 13. Rusk citrange and lemon, showing comparative amount of juice from 
 
 fruits of same volume " 234 
 
 III 
 
NEAV CITRUS CREATIONS OF THE DEPARTMENT OF 
 AGRICULTURE. 
 
 By Herbert J. Webber, in Charge of Ixiboratory of Plant Breeding, and Walter 
 
 T. Swingle, in Charge of Laboratory of Plant Life History, 
 
 Vegetable Pathological and Physiological Investigations, Bureau Plant Industry. 
 
 Introduction. 
 
 For a period of five 3'ears, from November, 1S92, to October, 1897, 
 the writers were associated in the study of diseases of citrus fruits in 
 Florida, being located at Eustis, in the central part of the State. A 
 careful study was made of the varieties cultivated and of the industry 
 in general, primarily as a basis for an intelligent investigation of the 
 diseases and methods of their control. In the course of these studies 
 the attention of the writers was early drawn to the desirability of 
 breeding more varied and improved sorts. 
 
 An examination of the manner of origin of the various native sorts 
 shows that in almost all cases they originated as accidental seedlings. 
 Some growers made hybrids and used S3'stematic methods of breeding, 
 but the number of fruits which have originated in this wa}' are very 
 few indeed. The long time required to bring seedlings to bearing, 
 the cost of cultivation and manuring, and the uncertainty of results 
 have deterred growers from experimenting very extensively in this 
 field. Owing to these difficulties, it seemed from the nature of the 
 case that the investigations should ])e undertaken b}' the National 
 Department of Agriculture, in order that the necessar}' funds could 
 be provided and that the work could be carried on continuously for a 
 series of years. This course was approved, and, under instructions 
 from the Secretary of Agriculture, the writers, under assignment of 
 Dr. B. T. Galloway, now Chief of the Bureau of Plant Industry, in 
 the winter of 1892-93 made a careful study of the various citrus 
 varieties and began the work of hybridization as rapidl}' as the time 
 at their disposal would permit. These first attempts were largely pre- 
 liminary, and most of the seedlings obtained were lost in the great 
 freeze of 1S94-95, which killed to the ground all orange trees in the 
 northern and central parts of Florida. This seriously interrupted 
 the work and compelled its temporary abandonment, owing lo the fact 
 that no groves could be found in the State furnishing the conditions 
 necessary for carrying on hybridization. The experiments were taken 
 
 221 
 
222 YEARBOOK OF THE DEPARTMENT OF AGRICULTURE. 
 
 up again in the winter of 1896-97, when the writers made an extensive 
 series of crosses at Eustis and Braidentown, being assisted in the work 
 by Mr. Otis H. Gates. Again, in the springs of 1898 and 1899, one of 
 the writers made further crosses which resulted in greatly increasing 
 the number of h^^brids. There have now been produced a total of 
 1,780 hybrids, and these are being grown and tested under general 
 instructions from Mr. A. F. Woods, Pathologist and Physiologist of 
 the Bureau of Plant Industry. 
 
 In all of the operations of hybridization the greatest care was 
 taken to avoid contamination with pollen from other sources. In all 
 cases buds were selected for hybridizing before they had opened and 
 given opportunit}^ for cross-pollination. These were opened and emas- 
 culated, after which they were covered with paper bags to prevent the 
 access of insects bringing in pollen. When tlie emasculated l)ud had 
 matured sufficientl}^ to be receptive, the bag was removed and pollen 
 of the variety selected as the male parent was dusted over the pistil. 
 The bag was then replaced over the flower and left until fecundation 
 had taken place, after which it was removed and the flower labeled. 
 The flowers which were used for suppljdng pollen were also covered 
 with paper bags previous to their opening, to prevent insects from 
 leaving other pollen on them, which might be transferred in the oper- 
 ation of hybridization. 
 
 In much of the hj'bridization and breeding work which has been 
 carried on .b}^ dift'erent investigators little attention has been given to 
 the choice of the varieties used as parents and to the objects sought in 
 the experiments. The time of this haphazard work, however, is past, 
 as experience has demonstrated that it is far better for the experi- 
 menter to have a deflnite object in view and to select, as parents for 
 hybridization, varieties which possess the characters that it is desired to 
 combine in the hybrid. In the present experiments the following were 
 the primary objects sought: (1) Hardier varieties Avhich would endure 
 the occasional severe freezes which visit the orange sections, and, if 
 possible, varieties sufficiently hardy to be grown farther north than 
 the present citrus belt; (2) new fruits having the l90se, easil}" remov- 
 able rind of the mandarin and tangerine combined with the quality, 
 flavor, and size of the ordinar}^ sweet orange; (3) new fruits having 
 the sprightly acid flavor of the pomelo with the bitterness reduced, 
 and the loose, easily separable rind of the mandarin and tangerine; 
 and, (1) new fruits intermediate between the pomelo and the orange 
 which would possess desirable market qualities. 
 
 In all of the writers' experiments these primary objects have been 
 kept clearly in view, and varieties have been selected for hybridization 
 which by their combination would be likely to give hybrids having 
 the characters desired. As the hybrid fruits matured they were sent 
 to Washington, where the seeds were extracted and germinated in a 
 
np:w citrus creations. 223 
 
 greenhouse. When the 3'oung seedlings had reached a size of from 12 
 to 18 inches in height th(\v were sent to the Department's Subtropical 
 Garden at Miami, Vhx., whore they have since been grown under the 
 supervision of Prof. P. H. Rolfs. \\'li('n the seedlings were sent south 
 the tops veere cut back and the twigs used to furnish budwood for 
 budding proper stocks to <)l)tain trees for trial. These trees were 
 tested in cooperation with different growers, arrangements being 
 made with a number of intelligent, trustworthy growers to bud from 
 one to two stocks with each of these hybrids and grow them until 
 sufficient fruits had been produced to show their character and value. 
 In the case of the hybrids made with the idea of securing hardiness, trees 
 were budded and grown under the direct supervision of the Depart- 
 ment by ]\Ir. G. L. Taber, at Glen St. Mary, in northern Florida. 
 Owing to the conditions under which the various trees have been grown 
 very few of them have yet fruited. Several freezes have visited Florida 
 in the last five years, and in man}^ instances all of the h3^brid buds sent 
 to growlers have been killed. In l>ut few instances have large stocks 
 been used which would force the ))uds into earh' bearing; nevertheless, 
 several very promising new t3^pes have been produced, and without 
 doubt many more fruits of value will be obtained when all of the 
 hybrids have been brought into bearing. It should be noted that in 
 fruit trees of this sort all of the varieties are clo?is, that is, varieties 
 which are propagated by buds, grafts, or cuttings. A hybrid of value, 
 when once secured, can thus be propagated indetinitely by budding or 
 grafting, without awaiting fixation, as is necessary' in the case of plants 
 propagated by seed, where a desirable hybrid nuist be selected through 
 a numJjer of generations and bred to a lixed type that will come true 
 through the seed before it can l)c utilized. 
 
 Production of Hardy Citrus Fruits. 
 
 The citrus industry in Florida has frequently suffered from severe 
 freezes. The most disastrous of these probably were the freezes of 
 1835, 1886, and 1891:-95, which killed or seriousl}' injured almost every 
 tree in the State. Other minor freezes have occurred from time -to 
 time, which, while not so severe, have serioush' damaged man}- orange 
 groves. In California and Arizona, also, citrus trees arc frequentlj' 
 injured by severe cold. It is thus clear that the most desirable improve- 
 ment in the orange and other citrus fruits is the securing of varieties 
 which can endure lower degrees of temperature and which may be grown 
 throughout the present orange-producing sections without danger of 
 injury by cold. 
 
 In attempting to improve citrus fruits in hardiness, two methods 
 present tiiemselves. .One method would be to grow a large number 
 of seedlings and select from them the individuals which possess the 
 
22-1 YEARBOOK OF THE DEPARTMENT OF AGRICULTURE. 
 
 greatest degree of hardiness, and continue this selection throughout 
 numerous generations in the hope of augmenting any greater degree 
 of hardiness that might be discovered. To pursue this polic}^ with 
 citrus fruits would require so long a period to secure a.nj marked 
 results that the method is impracticable. This is shown by the 
 fact that for manj'^ years citrus growers have been making selec- 
 tions based on the hardiness of seedlings, and as 3^et no appreciable 
 advance has been made in this direction. 
 
 A second method would be to select some hardy wild or cultivated 
 type and cross this with the sweet orange or lemon in the hope of 
 obtaining good varieties, combining the hardiness of one with the good 
 fruit quality of the other. If such a hardy type exists, this method 
 would certainly seem to be the quickest and most practicable way of 
 securing hardy varieties. A species of citrus known as the trifoliate 
 orange ( Citrus trifoliatd) is such a hardy tj^pe, which can be grown 
 without protection as far north as Philadelphia. The common variety 
 of the trifoliate orange (PI. X) was introduced into this countrj' by the 
 late William Saunders, of the Department of Agriculture, in 1869. The 
 tree is small and bushj^ and very spiny, and the leaves are trifoliolate 
 and deciduous. It is quite commonly grown as a lawn tree in the 
 North and as a hedge plant in the South, while in the colder sections 
 of Florida it is used as a hardy stock on which to bud the common 
 orange and other citrus fruits. The fruit (PI. XII, fig. 4, and PI. XIII, 
 fig. 2) is round and small, ranging from li to 2 inches in diameter, and 
 is orange -colored. The surface is covered with minute fuzzy hairs and 
 is in most cases smooth, being rough only in the larger and more vigor- 
 ous specimens. The rind, which adheres tightly, is about one-sixteenth 
 inch in thickness. The pulp is acrid, bitter, and gummy, and the 
 enormous number of seeds leave little room for pulp. The fruit is 
 thus worthless as far as edible qualities are concerned. It is highly 
 ' aromatic and attractive in appearance, making the plant desirable 
 for ornamental purposes. Unfortunately, however, for its use in the 
 South, the tree is deciduous, losing its leaves in the fall, and in gen- 
 eral throughout this section an evergreen hedge is most desired. Not- 
 withstanding this, it is generally cultivated as a hedge plant because 
 of other qualities which make it desirable for this purpose. Its hardy 
 character, however, is the factor of importance in connection with the 
 experiments in the production of a hardy orange. 
 
 A second variety of the trifoliate orange, having rather larger 
 leaves and very large flowers, has been found growing in several 
 places in Washington, D. C, but has not been used in the present 
 experiments. 
 
 The first variety described, the ordinary trifoliate orange, was the 
 one used in the work of the writers, though the second might be more 
 promising to use with the lemon, and some of these crosses have been 
 
Yearbook U. S. Dept. of Agnculture, 1904. 
 
 Plate X. 
 
 Branch of Trifoliate Orange. 
 [.\l){)Ut oiK'-lmlf iiiitnnil si/e.] 
 
NEW ( ITKUS CREATIONS. 225 
 
 iiiiido. However, no fruits have thus far been obtained. All varieties 
 of tlie trifoliate group are deciduous, and ripen their fruit early in 
 the fall before frost. They are also late in blooming in the spring, the 
 flowers, which appear before the foliage, not even showing until the 
 common sweet orange is nearly through ])looming. The ti'ifoliate is 
 thus al)out two to three weeks later to start growth in the spring, and 
 is never caught by late frosts. The early ripening of the fruit in the 
 fall, moreover, allows the tree to become dormant at a time much 
 earlier than the connnon sweet orange, which is evergreen and inclined 
 to grow more or less through the winter during warm periods. 
 
 It is a Avell-known principle in plant breeding that in hybridization 
 tlie characters of races and species break up and become cond)ined in 
 different waj's in the hybrids. It would thus seem entirely pro))able 
 that by crossing and recrossing the common orange with the hardy 
 trifoliate orange a hybrid could ultimatelv be obtained combining the 
 desirable fruit characters of the former with the hardiness of the latter. 
 Many instances are recorded where hybrids have been obtained com- 
 bining certain characters of the parents, and a few cases are known of 
 hybrids which are intermediate in character of hardiness between the 
 j)arents. ])eing more tender than one parent and much hardier than the 
 other. The impro])abiIity of o))tainingthe hardy (luality in an orange 
 variety is thus not so great as one might be inclined to think. If, by 
 infusing the blood of the trifoliate orange into the sweet orange, we can 
 modify the season of growth of the latter and cause it to remain more 
 dormant during the winter i«id later into the spring, our ol)ject would be 
 accomplished. If, on the other hand, a hybi-id can l)e secured having an 
 entire segregation of the characters and combining the hardiness of the 
 trifoliate with the superior fruit qualities of the sweet orange, a far 
 greater success would be achieved. 
 
 The sweet orange and the trifoliate orange are very distinct in chai- 
 acter, and it has been found in the course of the experiments that they 
 are ver}' difficult to hybridize. Even by using the utmost care in the 
 process of hybridization only about 2 per cent of the flowers operated 
 upon set fruit. The process of crossing flowers of the trifoliate orange 
 with pollen of the ordinar}' orange is nuich more difficult than the 
 opposite cross where the orange is used as the female, as the flowers of 
 the trifoliate orange are quite small at tln^ time of emasculation, are 
 attached very lightl}', and are easily ])roken off or injured. It would 
 thus seem that the lack of success in getting fruits to set was caused 
 partiall}' by the injury to the flower in the process of emasculation. 
 This, however, is certainly not the oid\' reason for the small percentage 
 of fruits that set, as there is also a great loss when the reciprocal cross 
 is made; that is, when the common orange is used as the mother parent. 
 The seeds resulting frdm these crosses were also poor in germinativc 
 30536—05 2 
 
226 
 
 YEARBOOK OF THE DEPARTMENT OF AGRICULTURE. 
 
 power, not more than half of the seeds obtained finally producing seed- 
 ling's. In the course of the experiments, however, a number of h3"brids 
 were secured where both the common oi-ange and the trifoliate were 
 used as the seed-bearing parent. Some of these hj^brids plain h' show 
 the characteristics of l)oth parents and are doubtless true hybrids. Out 
 of 40 hybrids of the trifoliate orange crossed with the pollen of the sweet 
 orange, 29 resembled the former in habit and foliage characters, so 
 far as could be observed, while 11 were clearly intermediate in these 
 characters. These 11 intermediate plants are YGvy similar to each other, 
 deriving certain characters from each parent. 
 The leaves are trifoliolate in form and are nuich 
 larger in general than those of the normal tri- 
 foliate orange. The central leaflet has a ten- 
 dency to be much larger, but the lateral leaflets 
 remain about the size of those in the trifoliate 
 orange, and in some of the seedlings these lat- 
 eral leaflets tend to become abortive, thus 
 approximating the unifoliolate SAveet orange. 
 
 During these experiments it has been found 
 that some complexity is liable to arise, owing 
 to the polyembryonic nature of citrus fruits. 
 It is well known that seeds of various citrus 
 fruits frequently produce more than one seed- 
 ling. Instances have been noted where a single 
 seed has produced a;? many as 13 seedlings. In 
 cases where strikingly distinct types of citrus 
 fruits were crossed, the interesting observation 
 was made that where two or three seedlings 
 were developed from a single seed they not 
 infrequently showed marked foliage differences 
 (lig. 12). Strasburger, in his critical study of 
 
 Fig. 12.— Thr 
 
 from 
 
 (tangerine crossed with trifoli- 
 ate) ; seedling with trifoliolate 
 leaves (on the right) is a true 
 hybrid; the other two seed- 
 lings with tangerine-like 
 leaves are false hybrids. 
 
 a single seed of a hybrid the polycmbryouy of this group, found that the 
 
 embryos, other than those developed from the 
 fecundated egg cell, are derived from certain 
 cells of the nucellus, lying near the embryo 
 sac wall, which become specialized, grow, and 
 develop rapidly, and form a tissue mass, which pushes out into the 
 embryo sac and forms an embryo similar to that formed in the noi-mal 
 way from the egg cell. The embryos formed in this way Strasburger 
 called "adventive." If we correctly understand the action of fecun- 
 dation, it is clear that in this group only those embryos that develop from 
 the egg cell proper as a result of the fecundation would show an indi- 
 cation of hybridization. Since the adventive embryos develop directly 
 from the mother tissue, in these we should not expect to see any of 
 the characters of the male parent. This conclusion was reached by 
 
NKW flTRUS CREATIONS. 227 
 
 the writers early in tlio oxporiinoiits, Ix'foro the growilig of the .sood- 
 liii<>N had shown d(^tiiiitoly what would tako ])lact>, and the dcvolopiuent 
 of the hybrids has proved this conclusion to Ix' well founded. In sev- 
 eral hybrids of the sweet orange, which is unifoliolat(% with the trifoli- 
 ate oi-ange, which has trifoliolate leaves, where the former was used 
 as the female parent, two aiul tiiree seedlings have been produced frour 
 the same seed, one of which had trifoliolate leaves, showing clearly the 
 influence of the male pariMit, while the other oi- others had strictly 
 unifoliolate leaves exactly like the mother parent. It is certain in such 
 cases that the trifoliolate seedling inherits this character from the male 
 parent, and that the embryo from which it grew was devel()[)ed from 
 the vgg cell proper. The other seedlings in such cases which have 
 unifoliolate leaves were doubtless developed from the so-called adven- 
 ti\'C embryos. The same phenomenon has also l)een o))served where 
 the trifoliate orange was crossed with pollen of the common orange 
 and also in hybrids of the tangerine orange crossed with the common 
 orange (lig. 1'2). The ol)servations have been suffici«Mit to establish its 
 common occurrence in citrus hybridization. Attention was called to 
 this phenomenon by one of the writers" in February, IJJOO. 
 
 In hybridizing citrus fruits to secure improved sorts this eti'ect 
 unfortunately causes serious complications. In man^' cases citrus 
 hybrids resemble the female parent in foliage characters, or the parents 
 differ so little in their foliage characters that the hybrid can not be 
 clearly distinguished, and it may thus ))e seen that until the seedlings 
 fruit it is impossible to determine whether they are true hybrids or 
 simply false hyl)rids developed from adventive embryos. It will 
 thus be iuiavoidal)le in such work to grow many si'edlings which come 
 from adventi\e embryos and which are not true hyl)rids. Such false 
 hybrids ordinarily would not be expected to give valuable varieties, 
 and growing them greatly adds to the trouble and expense. 
 
 The increase in vigor which is comnionly exhibited by hybrids 
 between distinct parents is clearly shown l)y hyltrids between the trifoli- 
 ate and the common orange. Those which have intermediate charac- 
 ters, showing that they are true hybrids, are almost invarial)ly much 
 more vigorous than th(> se(Hllings of either parent. The hybrids which 
 exhibit no intermediate ciiiiriu'ters and are probsibly developed from 
 adventive embryos, do not exhibit this increased vigor. Illustrations 
 of this increase in vigor will l)e given later, 
 
 THK C'lTKANCK, A NkW (iKOUP OF C'lTKUS FrUITS. 
 
 In the cours(> of these exi)eriments two fruits have been produced 
 which are hybrids between the common sweet orange and the trifoliate 
 orange, and whicii promise to be of considerable value. They lie 
 
 « Webber, H. J., Conipfications in CitruH tlybricfization (-aused by Polyembryony. 
 Science, n. s., 11:H08, February 2'A, 1!»00. 
 
228 YEARBOOK OF THE DEPARTMENT OF AGRICULTURE. 
 
 about midway between the two parents, but are not sweet oranges, 
 trifoliate oranges, nor lemons, and are totally different from any 
 other group of citrus fruits. It therefore becomes necessary to refer 
 these hybrids to a new group of citrus fruits, and it is proposed to 
 call them "citranges," a term made up of the first sj^llable of the word 
 citrus and the last S3'llable of the word orange. The two varieties 
 which are to be referred to this group are described in detail below. 
 
 KUSK CITEANGE. 
 
 [PLATES XI ^ND XII, AND PLATE XIII, FIGURE 1.] 
 
 Name and origin. — The Rusk citrange originated as a hybrid 
 between the common orange (used as the female parent) and trifoliate 
 orange (used as the male parent). The trees are far more hardy than 
 the common orange, and produce a fruit intermediate in qualities 
 between the two parents. This being the first hard}" orange or 
 citrange produced, and belonging to an entirely new group of citrus 
 fruits which will doubtless become of v'ery great importance in 
 many parts of the world and be improved in a marked degree, has been 
 named the Rusl\ in honor of the first Secretary of Agi-iculture, Hon. 
 J. M. Rusk, under whose administration the first work on citrus fruits 
 in Florida was undertaken by the Department of Agriculture." 
 
 The Rusk citrange was one of three seedlings grown from a single 
 h^^brid fruit which developed in the grove of Col. G. H. Norton, at 
 Eustis, Fla. , in 1897. Two of the seedlings, from which several budded 
 trees have been grown, resemble the ordinary sweet orange in foliage 
 and general character, and are apparently false hj^brids from seeds of 
 adventivCj polyembryonic embryos, which, as explained above, are 
 developed from certain cells of the mother tissue without the inter- 
 vention of the male element. These two seedlings have unifoliolate 
 leaves, and are evergreen like the common orange, and while the}' 
 have not 3^et fruited, owing to the fact that they have been sev- 
 eral times frozen back, it is not expected that they will produce 
 anj'thing of value, nor, judging from a test already made, will they 
 produce hardier types. The other seedling. No. 716, was a strictly 
 intermediate type, having trifoliolate leaves similar to the male 
 parent, though rather larger (PI. XI). Even the first leaves of the 
 3'Oung seedling exhibited this character, and a photograph of a seed- 
 ling but slightl}^ over 1 inch high published b}" the writers at that 
 time plainh' shows this trifoliolate character.^ No. 716 was further- 
 more much larger and more vigorous than the other two seedlings, 
 
 «In the Cosmopolitan Magazine for July, 1904, Mr. H. Gilson Gardner referred 
 to this citrange as the Webber, but the writers suggest, with the approval of the- 
 Secretary of Agriculture, that it be known as the Rusk. 
 
 & Swingle and Webber, Hybrids and their Utilization in Plant Breeding, Yearbook 
 of the Department of Agriculture for 1897, p. 400, fig. 13. 
 
Yearbook U. S. Dept. of Agriculture, 1904 
 
 Plate XI. 
 
 Hybrid Seedlings of Common Orange (Female Parent^ and Trifoliate Orange 
 
 (Male Parenti. 
 
 [N.I. TIC, (.,1, riKht). Rusk citranso; Nos. 7U and 7I.\ .seedli.iKs from iIr. same fruit as .\„. Tic, 
 
 hut resembling the mother parent.] 
 
Yearbook U. S Oapt. of Agriculture, igO*. 
 
 PLATE XII. 
 
 
 3>y?cu 
 
 ▼ 
 
 iJ ScdiJt 
 
 MOEH A CO . B«\.TIMOnt 
 
 pRulib ui- (nu;:.h. <^iii\amGE AND TRIhULiAit UmANGE. Naiuk/xl biZt. 
 
 Fig. 1— Rusk Citranqe, in an early stage of maturity. Fig. 2— Rusk Citrange, fully mature 
 
 Fiq. 3— RUSK Citrange, cross-section of mature fruit, fig. 4— trifoliate orange. 
 
Yearbook U. S Dept. of Agriculture, 1904. 
 
 Plate XI 
 
 = O 
 
NEW riTRT^S CREATIONS. 229 
 
 showing an incroasi' in vigor, whith i.s sucli a marked character of 
 hyhrids in general. Trees were budded with these h3'brids in the 
 spring of 1899, in the nurser}' of Mr. G. L. Tal)(>r. at Gh^n St. Mar}', 
 Fhi. Tiie lirst fruits were received in September, 1902, one tree that 
 season l)earing about a dozen fruits. In the fall of 1903 the same 
 tree produced about a bushel of fruits, and several other ti'ees, l)udded 
 on trifoliate-orange stock, gave about a half-dozen fruits each. A 
 similar number was also produced in 1904. There have thus been pro- 
 duced sufficient fruits to afford a fairl}' thorough test of this hybrid. 
 
 Description of friit and tree. — Fruit compressed-spherical or nearly round; 
 small, U to 2 inches in diameter, 1} to 1| inches high; color, when fully mature, 
 deep orange, with reddish flush of cadmium orange at apex; surface smooth and 
 glossy, with a few scanty hairs visible under niagnitication; very heavy, freciuently 
 sinking in water; calyx persistent, green, rather larger than that of the ordinary 
 orange; skin adhering very close to the fruit, thin, -/_, to J incii tliiek, tender; oil 
 glands small and round; i)ulp tender, melting, exceptionally juicy (lig. 13); color 
 orange yellow; pulp cells small, similar in shape to those of ordinary orange; seg- 
 ments, 10; membranes thin and tender, thus making very little rag; axis small, 
 J to /,. inch in diameter; flavor sprightly acid and slightly bitter; nearly seedless, 
 averaging one seed to two fruits; aroma strong and ])lcasant, a combination of that 
 of tiie sweet orange and the trifoliate orange. Tree similar in shape to trifoliate 
 orange, vigorous and hardy, evergreen or semi-evergreen, tall and shapely; foliage 
 dense, leaves trifoliolate and larger than those of ordinary trifoliate orange. Season 
 of maturity very early, from Sej)tendjer 1 to November 1. 
 
 The fruit of the Husk is a beautiful little orange of excellent texture 
 and exceedingly juic}'. It is rather too sour to be eaten out of hand, but 
 with sugar is very palatable. The bitterness is no more pronounced 
 than in the grape fruit, and the aroma, which is derived largel}' from 
 the trifoliate orange, is very strong and pleasant. The fruit of the 
 Rusk may be utilized for making citrangeade, similar to lemonade or 
 limeade, or ma}' be eaten with sugar as a breakfast fruit. It also 
 makes excellent pies, preserves, and marmalade, and may bo used for 
 general culinary purposes. 
 
 WILLirS ("ITHANOE. 
 
 [PLATK XIII, FIGURE ;',. PLATE XIV (777), AND PLATE XVL] 
 
 Name and origin. — The second citrange which has given evidence 
 of value has resulted from a hybrid of trifoliate orange with pollen 
 of the common orange, being thus what is known as a reciprocal 
 hybrid of the Rusk citrange. In general it possesses characters inter- 
 mediate l)etween the two parental varieties, and is similar to the Rusk 
 in tree and fruit characters, yet differing considerably in detail, so that 
 there is no trouble in clearly distinguishing it from the Rusk citrange." 
 
 aThis citrange the writers propose, with the approval of the Secretary of Agricul- 
 ture, to call the Willilf!. In the Cosmopolitan Magazine for July, U>04, Mr. (iardner 
 called this citrange the SwuKjlr, but the writers would prefer that it be known as the 
 PTiWita, in honor of the First Assistant Secretary of Agri<-ulture, lion. Kdwiu Willits. 
 
280 YEARBOOK OF THE DEPARTMENT OF AGRICULTURE. 
 
 The Willits citrange was one of 40 seedlings from a single hybrid 
 fruit grown and developed in the grove of the late Col. G. H. Norton, 
 at Eustis, Fla. Of the 40 hybrids of this series 11 exhibited char- 
 acters clearl}^ intermediate between the two parents, being evergreen 
 and having trifoliolate leaves much larger than those of the trifoliate 
 orange (PI. XIV). The remaining 29 seedlings are all deciduous and 
 have leaves apparently like the tj'pical trifoliate orange. Eighteen of 
 these have fruited and all produced fruits indistinguishable from the 
 trifoliate orange. It would thus seem clear that the 29 which resem- 
 ble the trifoliate parent are false hj^brids, having developed from 
 adventive embryos, as already explained. Four of the apparently 
 intermediate seedlings have fruited, and all have given fruits clearly 
 partaking of the nature of both parents. These are, therefore, cer- 
 tainly true hybrids. 
 
 All of the h3'brids of this series which show intermediate characters 
 are exceptionally vigorous, showing in this regard also their true 
 hybrid nature. The smallest of them was as large as the largest of 
 the seedlings which exhibited no intermediate characters. The vigor 
 of the young hj'brid seedlings in comparison with both parents and 
 the comparative size of leaves is shown in Plate XV. Here No. 845, 
 a cross of two typical oranges and one of the largest of 500 seedling 
 oranges of similar kind, is 3'et far smaller than the medium-sized true 
 hybi-id No. 772. No. 780, one of the largest of the 29 false h3^brids, 
 affords a comparison of the size of the true h3'brids with the t3'pe of 
 the mother parent. The true h3'brid No. 772, used here for com- 
 parison, is not the largest of the hybrids secured, but is of medium 
 .size. The h3'brids between distinct species and races are ordinarily 
 intermediate between the two parents and mainly very uniform, so 
 that the hybrids of the lirst generation usuall3' resemble each other 
 ver3' closel3\ In the case of the h3^brids between the trifoliate orange 
 and the common orange, however, the seedlings have been found to 
 differ from each other verv markedly. The fruits of all of those 
 which have thus far come into bearing are essentialh^ distinct in 
 flavor, size, and appearance. Tlie seedlings also differ in tree and 
 foliage characters. They are all similar, however, in having fruits 
 iiearl3^ intermediate in size, with some of the bitter flavor of the tri- 
 foliate fruit, and in having trifoliolate leaves and semi-evergreen 
 foliage. The difference in foliage characters of some of these hybrids 
 and their parents is shown in Plates XIV and XV. 
 
 Description of fruit and tree. — Fruit compressed -spherical, or nearly round; 
 small, from 1 1 to- 2 1 inches in diameter (PI. XIII, fig. 3, and PI. XVI), and from 1^ 
 to 2 inches in height; color from cadmium yellow to orange; surface rough with deep 
 depressions over the largest oil glands, and with more or less pronounced furrows or 
 ridges running from base to apex; weight medium, about the same as water or 
 somewhat lighter; calyx persistent, with large and fleshy lobes; rind thin, J inch in 
 
Yeaibook U. S. Dept. of Agriculture, 1904 
 
 Plate XIV 
 
 »*•» 
 
 
 33 
 
 
 3*2 
 
 ^ 
 
 31 
 
 ^^/C- 
 
 30 
 
 NT 
 
 29 
 
 x- T/»- 
 
 a? 
 
 ll^ 
 
 27 
 
 ^ 
 
 26 
 
 V 
 
 Seedling Hybrids of Trifoliate Orange Crossed with Pollen of the Common 
 
 Orange. 
 [No 776 IV false hvbri.l, sliowinj,' no intemiediale churacters and having small .lofiduous leaves: 
 No 777, seedling of Willits citranKe. showing the evergreen foliage and other nitermediate 
 characters: Nos. 77S and 779, two seedlings grown from the same seed. No. 779 (on the right), 
 showing intermediate characters. No. 778 (on the left), showing only the normal characters of 
 the Irifoliate orange.] 
 
Yearbook U. S. Dept. of Agriculture, 1904. 
 
 Plate XV. 
 
 Seedlings of Citrus Hybrids, Showing Relative Vigor of True and False 
 
 Hybrids. 
 
 [No. 780. a false hybrid (trifoliate x swei't orange); No. 772, a true intermediate hybrid (trifoliate x 
 sweet (iraiifie), with large trifoliolate leaves; No. 845, a eross of two ordinary orange varieties. 
 All seedlings of .same age.] 
 
Yearbook U.S,Oept.o.AgMCultur.M 904. 
 
 PLATE XVI. 
 
 'i>69a 
 
 aA^>^^(y^<^ 
 
 HOV * CO , B»l.TlMORt 
 
 WlLLITS CiTRANGE. NATURAL SIZE. 
 
NKW CITUrs CKKATIONS. 231 
 
 thii'knesH, and triKlor, not adlu'rinjj jjo closf to fniit as in tlie Rusk citrange; pulp 
 translucent, light lemon yellow, re.-enihling the onlinaiy lemon; Hegments 6 to 10, 
 separated hy thin tender membranes; texture of fruit very tender, being ecpial to 
 that of the best lemon; axis small, about J ineh in diameter; flavor sprightly aeitl, 
 similar to lemon, with very slight l)itter taste of trifoliate orange; nearly seedless, 
 averaging about one seed to four fruits; aroma mild and pleasant, combining the 
 aromatic resinous odor of the trifoliate orange with the very delicate odor of the 
 eommon orange. Trees similar to trifoliate orange, vigorous and hardy, evergreen 
 or semi-evergreen, medium height and shapely; foliage dense, leaves trifoliolate and 
 larger than those of the ordinary trifoliate orange (PI. XIV); season of maturity very 
 early, from September to the last of November. 
 
 The Willits citrange makes a beautiful, vigorous-oiowino- tiee and 
 gives evidence of l)eino- of value as a decorative or lawn tree. The fruit 
 makes a tine drink similar to lemonade or limeade and will he found 
 pleasant as an acid fruit to eat witii sugar. It is an excellent ."substitute 
 for the lemon to serve with fish or 03^sters and is valuable also for culi- 
 nary pui'iwses, for which its seedlessness renders it specially desirable. 
 The products made from the Willits citrange are very diti'erent in 
 flavor from those made from the Rusk citrange. Thej' possess more 
 nearly the charactcn- and flavor of those made from the lemon. 
 
 HOW UAI!I)V IS THK CITRANGE? 
 
 All of the diti'erent citrange seedlings were budded on trifoliate 
 orange stocks at Glen St. Mar}', in northern Florida, in the spring of 
 1899. In January of 1900, when the i)uds were about 8 months old, 
 a severe freeze occurred in which the temperature went down to about 
 15^' or 18^ F. Mr. Taber recorded a temperature of 18" above zero at 
 Glen St. Mary. At Macclenny, Fla., 3 miles east of Glen St. Mary, 
 a minimum temperature of 15° was recorded, while at Lake City, 
 about 20 miles west, the minimum temperature recorded was 17° F., 
 the record at Macclenny and Lake City being made b}'^ voluntary 
 observers of the United States Weather Bureau with speciall}' corrected 
 instruments. After this freeze a report from Mr. Talker stated that 
 the foliage on the buds of Rusk (No. 716) and Willits (No. 777) 
 citranges still remained gi'een on the tree, and that the tops w^ere 
 apparently entirely uninjured. All of the hybrids between the tri- 
 foliate orange and the coimnon orange which show intermediate char- 
 acters also remained uninjured and retained their foliage fresh and 
 green, with the exception of an occasional twig which at the time of 
 the freeze was soft and immature. 
 
 In this freeze ordinary oranges suffered severely, large buds in 
 many parts of the Sbite l)eing frozen to the groimd, and this was the 
 ca.se with ordinary oi'ange buds growing immediately beside the 
 citranges at (ilen St. •Mary. Although no freeze which has occurred 
 since has l)een so severe, temperatures of from 20° to 23 have been 
 
232 YEAKBOOK OF THE DEPARTMENT OF AGRICULTURE. 
 
 several times recorded. In none of these freezes have the citranges 
 been injured, although buds of ordinar}^ oranges have frequently been 
 severely damaged. 
 
 Aside from the tests made at Glen St. Mary, Fla., sets of the h3'brids 
 which had been made with the idea of producing hardy varieties were 
 sent- to the Florida, Georgia, South Carolina, Alabama, and Louisiana 
 experiment stations to be grown and tested in cooperation with the 
 Department of Agriculture. These were planted in March, 1900. At 
 the experiment station at Lake City, Fla., which is in about the same 
 latitude as Glen St. Mary, the trees have passed through the winters 
 since March of 1900 without serious injury. Here the trees have 
 been grown under the direction of Prof. H. Harold Hume, who 
 reports that the temperature has several times fallen to a point where 
 all ordinary orange trees were severelj^ injured or killed without 
 resulting in injury to the Rusk or Willits citranges or to the other 
 hybrids of intermediate nature. Professor Hume reports that the 
 minimum temperature recorded during this period was 21° in Decem- 
 ber of 1901. 
 
 At the Georgia experiment station a set of the trees has been tested 
 under the supervision of Director R. J. Redding and Prof. H. N. 
 Starnes. At this place the temperature fell in Februar}", 1901, to 17° F. 
 above zero, and in December, 1901, to 8°. The majority of the inter- 
 mediate h3^brids passed through these freezes without serious injur3^ 
 The Rusk citrangc was killed back to some extent, but lived through, 
 and is now reported to be in good condition. The trees of the Willits 
 citrange planted at this station have died, but whether directly from 
 the effects of the cold is not certain. 
 
 At the Alabama experiment station, Auburn, Ala., a set of the 
 trees has been grown under the supervision of Professors Earle and 
 Mackintosh. At Opelika, Ala,, about 10 miles distant, the lowest 
 temperature recorded, since the trees were planted, was 9° F. above 
 zero in December, 1901. Trees of the Willits have remained uninjured, 
 while trees of the Rusk citrange are all reported as dead. Here again, 
 however, it is not clear from the records whether they died as a result 
 of injury from freezing, although this might be assumed. However, 
 almost all of the strictl}' intermediate hybrids hiave survived the winters 
 at this place without serious injur3\ 
 
 At the South Carolina experiment station, Clemson College, S. C, 
 a number of the hvbrid trees have been grown and tested under the 
 supervision of Prof. C.C. Newman. Unfortunately a complete set 
 of the hj^brids was not sent to all of the cooperating stations, owing 
 to a lack of trees of certain numbers. It happened that neither the 
 Rusk nor the Willits citrange was among the number sent to the 
 South Carolina station. However, a number of the intermediate 
 
NEW CITRUS CREATIONS. 233 
 
 livbrids similar to the Rusk and Willits citranges have been grown 
 and tested at this station, and have passed through the winters 
 since March, 1900, without serious injury. At this station they liave 
 endured a mininumi temperature of G^ F. above zero, which occurred 
 in December, 1901. 
 
 At the Louisiana experiment station a set of the h3')jrids, among 
 them the Rusk and Willits citranges, have been tested under the innuedi- 
 ate supervision of Dr. W. C Stubbs. At this station the temperature 
 in December, 1901, fell to 21^^ F. above zero, and remained ])elow 2(P 
 above zero for nearh' a week. All of the h3^brids survived the freez- 
 ing without serious injury, although trees of the ordinary orange in the 
 vicinity were in many cases killed. 
 
 It will be noticed from the above tests that both the Rusk and the Wil- 
 lits citranges are nuich hardier than ordinary oranges. While the 
 Rusk citrange endured the freeze of December, 1901, at Experiment, 
 Ga., it was killed, or at least died, at Auburn, Ala. On the other 
 hand, the Willits citrange died at the Georgia experiment station 
 and survived at the Alabama experiment station. It is well known 
 that the condition of a tree at the time a freeze occurs has a great 
 deal to do with its hardiness. Trees which endure the most severe 
 winters at the latitude of Washington, D. C, have been killed in some 
 of the freezes in Florida, owing to the fact that they were in a sappy, 
 growing condition at the time the freeze occurred. That some of these 
 citrange trees were killed, therefore, at certain stations does not indi- 
 cate that thev are tender. The fact that the}' have survived the same 
 degree of cold at other stations indicates that they would have sur- 
 vived in all cases had they been in a properly dormant condition. It 
 is believed from the evidence now accunuilated that these two cit- 
 ranges ma}' be grown without protection throughout South Carolina, 
 Georgia, Alabama, Mississippi, Louisiana, Arkansas, and parts of Ten- 
 nessee and Texas. It is also pro})able that the}' can be grown in parts 
 of Washington and Oregon, and in northern California, which are only 
 slightly too cold for the orange, and in certain irrigated regions of low 
 altitude in Arizona and possibly New Mexico. It will be remembered 
 that the peach tree, which is considered to he fairly hardy, sutlered very 
 severely in Georgia in the freeze of December, 1901, to which these 
 citranges were exposed. Large peach trees were frozen to the ground, 
 and the damage to the peach industry was very great. The range of 
 latitude at which the citrange may be safely grown has not been fully 
 determined, but it is believed that they will succeed in any of the 
 aboA'e-named places where the altitude is not too high. 
 
234 
 
 YEARBOOK OF THE DEPARTMENT OF AGRICULTURE. 
 
 OF WHAT VALUE IS THE CITRANGE? 
 
 The fruits of the citranges thus far produced are small, acid, and 
 bitter, and from the standpoint of the ordinary orange grower would 
 be considered practically worthless. This opinion, however, would be 
 based entirely on a comparison of the citranges with oranges of fine 
 quality such as are produced in Florida and California. When it is 
 considered that these fruits can be grown through the Gulf and South 
 Atlantic States without protection, where there is now a dearth of 
 acid fruits, their great value can be understood. Both the Rusk 
 and the Willits citranges make a refreshing '* citrangeade," similar 
 to lemonade and limeade. It is also very similar to the orangeade 
 
 Fig. 13. — Rusk citrange (on left) and lemon (on right), showing comparative amount of juice from 
 fruits of same volume. (Five-eighths natural size.) 
 
 made from the native sour oranges of Florida. The citrangeade has 
 been tested by a large number of people, and all who have made a 
 comparison pronounce it fully equal to lemonade or limeade, while 
 some think it superior. The fruits are exceptionally juicy, the Rusk 
 citrange in particular giying a much larger proportion of juice than 
 the best lemons on the market (tig. 13). The fruits make excellent 
 pies and marmalade, and for this purpose they are probably equal 
 to the orange or lemon. Fortunately, the pies and marmalade 
 made from the two fruits are of distinctly different qualit}^ and both 
 differ again from the lemon in this respect. The Rusk citrange 
 
NEW CITRUS CREATIONS. 235 
 
 has also been found to nmko un oxcolloiit i)re.servo. The fruits will 
 probably prove valuable for jrenoral culinary purposes in the making- 
 and tlavoring- of oakos. for use in niakino- jellies whore lemons are 
 now employed, and probably in many other waN's. While they are 
 too acid to eat out of the hand they will be found very palatable to any- 
 one enjoyinj^: an acid fruit, especially when eaten with sugar. The 
 citrange will prol)ably prove of vahu? mainly as a home fruit for culti- 
 vation throughout the Southern States mentioned above, where the 
 sweet orange, the lemon, and the lime can not be grown, A few trees 
 should be cultivated in every yard in this section. The trees are 
 attractive in shape and semi -evergreen, so that they will make desirable 
 lawn trees. Wherever a home can be supplied with them, it will be 
 possible on the warm days between the 1st of September and the 1st 
 of November to pick a few fruits and make a desirable, refreshing- 
 beverage. It is believed that they will prove a decided ])oon to a very 
 large section of the country. While the fruits already obtained present 
 results far-reaching and important, even more striking and valuable 
 results will doubtless be obtained when seed from these fruits can be 
 grown and selections of the best citranges made from among their 
 progen}'. These two citranges, it is confidently believed, will be the 
 progenitors of a large and numerous group of hardy, edible fruits. 
 
 The Tangelo, a New Groui' of Loose-Skinned Citrus Fruits. 
 
 During the course of these experiments a hybrid has been produced 
 between the pomelo and tangerine which occupies a position interme- 
 diate between these two well-known fruits. It is neither a pomelo 
 nor a tangerine, but is different and unique and bids fair to take a 
 place by itself. The fruit is intermediate in size between the two 
 parental varieties, has the easily removable rind of the tangerine, and 
 in flavor is somewhat sweeter than the pomelo, with less bitterness. 
 It is distinct from any of the various groups of citrus fruits and 
 should, therefore, be referred to a new group. The term "'tangelo*' 
 is suggested by the writers as a name for this group of loose-skinned 
 fruits, which lie midway between the pomelo and tangerine, the word 
 being a coml)ination of the tirst syllable of the word t(i)i</erh>i', with 
 the ending of the word potne/o. A variety of citrus fruits known as 
 the '' nocatee,"' which has already been described and introduced, is 
 apparently somewhat similar to this fruit and is evidently a hybrid 
 between the tang-erine and pomelo. This and the new Sampson tan- 
 gelo which is described below, are at present the only two varieties 
 that can be referred to the tangelo group. 
 
236 YEARBOOK OF THE DEPAETMENT OF AGRICULTURE. 
 
 THE SAMPSON TANGELO. 
 
 [PLATES XVII, XVIir, AND XIX.] 
 
 Name and origin. — The Sampson tangelo is a hybrid between the 
 ordinary pomelo (female parent) and the Dancey tangerine (male 
 parent). The fruit from which the seedlings came was from a cross 
 made in the grove of Mr. Frank Savage, at Eustis, Fla. The hybrid 
 fruit contained a very large number of seeds, 76 in all, which gave a 
 total of 106 seedlings, several of the seeds having produced more than 
 one seedling. A large majorit}^ of these seedlings have not yet fruited, 
 but of those that have borne fruit all have the appearance of pure 
 pomelo, except No. 1316, which exhibits characters plainlj- interme- 
 diate between the pomelo and the tangerine, being about midway 
 between the two in size and other characteristics. The color of the 
 fruit is darker orange than the pomelo, though not so red as the tan- 
 gerine, and the color of the pulp is more nearly like the tangerine 
 than any of the varieties of the pomelo. In flavor it is sprightly acid, 
 but rather sweeter than the pomelo, and it has a slightly bitter taste 
 derived from that parent. Its most pronounced characters, however, 
 are the looseness of the rind and the ease with which the segments can 
 be separated; in these qualities it partakes of the nature of the tan- 
 gerine. The fruit may be described as a small " kid-glove'' pomelo. 
 
 The hybrid seedling from which this variet}^ developed was grown 
 and fruited by Mr. F. G. Sampson, of Boardman, Fla., who since the 
 beginning of the citrus experiments of the Department has given 
 material aid in man}^ ways. The writers therefore take pleasure in 
 suggesting for this new tangelo the name of Sampson, in recognition 
 of his aid in connection with the experiments. 
 
 Of the 106 seedlings of the series from which the kSampson origi- 
 nated, 5 have leaves with narrow, winged petioles, the foliage resem- 
 bling more closely the tangerine than the pomelo. The only one of 
 these that has thus far fruited is No. 1316, the Sampson, which, as 
 indicated above, in fruit characters clearly exhibits its true hybrid 
 nature. The other 101 seedlings have foliage which would be classed 
 as purely pomelo in character. Only 6 of these have thus far borne 
 fruit, and all of the fruits produced resembled pure pomelo. From 
 these observations it would seem that only the 5 seedlings having 
 tangerine-like foliage are in reality true hybrids. The others are 
 probably false hybrids, developed from adventive embryos. 
 
 Description of fruit and tree. — Fruit compressed-spherical, slightly drawa 
 out at stem end like tangerine; of medium size, averaging 2^ inches in diameter 
 and about 2| inches in height; weight from 163 to 248 grams; calyx persistent as in 
 common orange; color chrome yellow, considerably darker than the pomelo, though 
 not so red as the tangerine; specific gravity about the same as water; skin thin, about 
 one-eighth of an inch in thickness, loose and easily removable, like the skin of the 
 
Yearbook U. 5. Dept. of Agripulturo, 1904. 
 
 "PSTa 
 
 ad^fi^o'X^ 
 
 HOex 4 CO , ■«LTIMOIIC 
 
 Sampson Tangelo. Natural size. 
 
Yearbook U. S. Dept. of Agriculture, 1904 
 
 Plate XVIII 
 
 <^ 
 
 \ 
 
 Sampson Tangelo, Showing Easily Removable Rind. 
 IN.itviral sizf.l 
 
Yearbook U. S. Dept. of Agricul-.ure, 1904. 
 
 Plate XIX. 
 
 Sampson Tanqelo Above; Ordinary Pomelo Below. 
 [Niituriil size.] 
 
NEW CITRUS CREATIONS. 237 
 
 tangerine; surface pmooth and glossy; oil glands large and conspicuous, rendering the 
 rind translucent; larger glands oblate sjiherical, smaller ones nearly spherical; seg- 
 ments 9 to 11, separating ea^iily like tangerine; menihranes thin and tender; axes small 
 and compact, about one-half inch in diameter; rag very slight; quality excellent; tex- 
 ture very tender and juicy; Havor sprightly subacid, somewhat sweeter than pomelo, 
 but with more acid than the tangerine and with a slight l)itter taste derivetl from the 
 pomelo; color of pulp, ochraceous-buff to orange buff, differing in this respect from 
 both parents; seeds 10 to 15, medium in size; aroma slight, giving suggestion of 
 both parents; in general appearance very attractive, resembling small pomelo, but of 
 rather darker orange color; tree evergreen, tender, vigorous, and productive, having 
 general character of ordinary tangerine; leaves unifoliolate, with comparatively 
 narrow petioles like tangerine. 
 
 USES OF THE TANC.ELO. 
 
 The Nocatee tangelo, which has l)een previous]}' described, is not 
 familiar to the writers, and they are unable to pronounce on its value. 
 The Sampson tangelo, however, is ver}' likely to become an important 
 commercial fruit. Those who have tasted it pronounce its flavor 
 excellent. Its ver}' attractive appearance and color of flesh, together 
 with the ease with which it can be peeled and the seg-ments separated, 
 favor its growth in popularity. The bitter taste which is so pro- 
 nounced in the pomelo is in the Sampson tangelo reduced to a sug- 
 gestion which only adds to its sprightliness. Altogether it is a sprightly 
 acid, highly flavored fruit, being not so acid as the pomelo and not so 
 sweet as the tangerine, and it is believed that many people will prefer 
 it to either of these fruits. It is a vigorous grower and probably produc- 
 tive. It is of course no hardier than either parent and can be grown 
 onl}' in the orange belts of Florida and California. It is believed that 
 the Sampson tangelo will become a popular breakfast fruit, to be used 
 by peeling and separating the segments, as in the case of the tangerine, 
 and eaten by dipping the segments in sugar. The popularit}' of the 
 pomelo, or grape fruit, is due largely to its use as a breakfast appe- 
 tizer, and it is recognized as especially beneficial for invalids. It is 
 also thought that the bitter element, probably due to some alkaloid, 
 furnishes a slight healthful stimulation. The pomelo, however, is too 
 bitter and acid to suit the taste of many. The Sampson tangelo, 
 being somewhat sweeter and lacking much of the bitter taste, would 
 seem to furnish a happy medium between the tangerine and pomelo, 
 which would recommend it to man}- who tind the pomelo too harsh. 
 In some ways the flavor of the tangelo resembles the most improved 
 bitter-sweet orange, ])ut is certainly superior to it. Altogether, it is 
 believed that the fruit will occupy a place not now filled ))y any other 
 citrus fruit and that it will become valuable for commercial cultivation. 
 Its superior quality and the ''kid-glove" character of the rind mark 
 it as a distinct and most valuable creatiou. 
 
238 yearbook of the department of agriculture. 
 
 New Tangerine Oranges. 
 [plates xx, xxi, and xxii.] 
 
 One of the primary objects in the citrus breeding experiments was 
 to produce hybrids l^etween the common sweet orange and tangerine 
 in order to secure a new fruit having the size, quality, and flavor of 
 the ordinaiT orange combined with the loose, easily removable rind of 
 the tangerine. A few of these hj'brids have now fruited, and two of 
 them, crosses of the Dancey tangerine with pollen of the Parson Brown 
 orange, have produced fruits which are of considerable value. Both 
 of these seedlings were grown from one fruit which was the result of 
 a cross made in the grove of Mr. W. K. Trimble, of Braidentown, Fla. 
 While the fruits were supposed to be hybrids, the}' nevertheless 
 resemble the tangerine orange in all important characters, difi'ering 
 from the Dancey tangerine, which was used as the mother parent, 
 mainly in being larger and considerably earlier in time of maturity and 
 in being of rather better quality. 
 
 THE WE8HART TANGERINE. 
 
 Name. — One of these new tangerines, the Weshart (Pis. XX and 
 XXI), is. named in honor of Mr. W. S. Hart, of Hawks Park, Fla., in 
 recognition of his valuable assistance in these experiments. Both of the 
 new tangerine oranges were grown and fruited under his supervision. 
 
 Description op fruit and tree. — Fruit compressed-spherical, slightly protruded at 
 stem end and somewhat depressed at the apex, having the same general form as the tan- 
 gerine. Size from 2^ to 3/'j inches in diameter, averaging about 3 inches. Height from 
 2\ to 21 inches. Color deep orange red, like tangerine. Surface smooth, glossy, and 
 very attractive, much smoother than the Trimble tangerine, to be described later. 
 Rind loose, as in other varieties of this group; thin, from /o to J inch thick. Oil 
 glands medium size, surface of rind slightly sunken over the largest. Segments 
 mainly 10, easily separable. Membranes tender. Axis hollow, from | to 1 inch in 
 diameter, star-shaped. Rag tender and in moderate quantity. Quality and texture 
 excellent. Flavor sweet, subacid, very juicy. Bouquet characteristic and very 
 pleasant. Color of pulp buff orange; cells small like ordinary tangerine. Seeds few, 
 from 9 to 15. Tree vigorous and prolific. Foliage branching, and shape of tree like 
 the tangerine. Season A'ery early for tangerine. 
 
 The AVeshart tangerine is a delicious fruit of exceptionalh^ line 
 appearance and flavor. Its large size, superior quality, and earliness 
 indicate that it will prove of great value for general cultivation in 
 orange regions. In general it is smoother in surface and rather smaller 
 than the Trimble tangerine, but is apparently superior in flavor. 
 
 THE TRIMBLE TANGERINE. 
 
 Name.— The Trimble tangerine (PI. XXII) is named after Mr. W. K. 
 Trimble, of Braidentown, Fla., in whose grove the original hybrid was 
 produced. The resulting seedling was grown and tested in the grove 
 of Mr. W. S. Hart, of Hawks Park, Fla., as was also the Weshart 
 tangerine. 
 
Yearbook U. S. Ospt. of Agriculture. 1904. 
 
 ■k^fe 
 
 n9a 
 
 aAti-'f^Lcyx^ 
 
 MOeN A CO . BALTIWORt 
 
 Weshart Tangerine. Natural size. 
 
Yearbook U. S. Dept. of Agriculture, 1904. 
 
 Plate XXI. 
 
 O 
 
 o 
 
 
Yearbook U. S. Dept. of Agriculture, 1904. 
 
 PLATE XXII. 
 
 w 
 
 3>y?a 
 
 ada^fn.O-'H^ 
 
 MOLh A CO . BALTIMORC 
 
 Trimble Tangerine. Natural size. 
 
NEW CITRUS CREATIONS. 2'6\) 
 
 Pes(RIPTiox ok frcit Axn tkee.— Fruit ronipresyed-yiiheriral, of pame shape as 
 the Wei?hart tangerine, and with t^Hghtly protruded stem end and depression at 
 apex. Size large, from 3 to 3| inches in diameter and from 2 to 2f inches in height. 
 Heavy, averaging ahout 5.6 ounces. Color deep orange red, like Dancey tangerine, or 
 slightly darker. Surface somewhat rough and bumpy, in larger specimens similar 
 to King orange; frequently with slight grooves running from base to apex. Oil glands 
 small, with the surfaceof the rind slightly sunken over the larger ones. Rind loose, 
 thin, 5^*2 to J inch in thickness. Segments 9 to 11. ^rend)ranes thin and tender. Axis 
 I inch in diameter and hollow. Kag comparatively little for fruit of this class. Flesh 
 deep orange yellow and very attractive, tender, and juicy. Pulp cells medium size. 
 Flavor sprightly acid and excellent, with pronounced bouquet. Seeds few, averaging 
 about 10. Tree vigorous and prolific. Foliage branching, and shape of tree like 
 Dancey tangerine. Season of maturity very early for tangerine. 
 
 The Trimble tangerine is a fine large tangerine, the rough, bumpy 
 appearance serving to distinguish it from other tangerines, and at the 
 same time not detracting from its appearance. In general the fruits 
 are somewhat larger than those of the Weshart tangerine, but are 
 slightly inferior to them in flavor. 
 
 GENERAL QUALITIES OF NEW TANGERINES. 
 
 The Weshart and Trimble tangerines, it will be seen from the above 
 descriptions, differ from other varieties of tangerines primarily in 
 being larger and earlier and more highl}' flavored. Fruits of these 
 two varieties have been received in some quantity for the past two 
 seasons, and have been compared with those of the Dance}' tanger- 
 ine, grown In' Mr. W. 8. Hart in the same grove, and with the best 
 tangerines that could be procured on the market. In every case 
 the}' have been superior in color, size, and flavor. In Mr. Hart's 
 grove the\' have uniforml}^ colored up and ripened about two weeks 
 earlier than the Dancey tangerine, and it would thus seem that they 
 ma}' be highly reconunended for general culture. They have not been 
 tested in any other parts of Florida nor in California, and it can not 
 be definitely stated what they will do under difl'erent conditions. The 
 Dancey tangerine, however, is generally cultivated, and it is believed 
 that the new fruits will prove superior to this variety in almost every 
 respect. While these two tangerines developed from a fruit of Dancey 
 tangerine crossed with pollen of Par.son Brown, they show no clear 
 indication of intermediate characters (PI. XXI). They are in every 
 respect, .so far as can be judged, true tangerines. The Parson Brown 
 orange, which was used as the male parent, is a typical orange and one 
 of the earliest varieties cultivated. The new fruits are larger than tho.se 
 of the tangerine, and it may be that the large size, and their earliness, 
 are qualities derived from the Parson Brown. If it were not for the 
 possibility of their lijiving developed from adventive embryos, this 
 would be the normal conclusion. It is, however, impossible to deter- 
 mine this matter from the characters exhibited by the trees up to the 
 
240 YEARBOOK OF THE DEPARTMENT 
 
 present time. As the trees mature othei ® ^^^ 
 
 visible which may throw some light upou tuis point. I'racticall}" 
 speaking, however, it does not matter whether the new fruits have 
 any orange blood in them, so long as they possess valuable qualities. 
 The Weshart and Trimble, it should be remembered, are tangerine 
 varieties, and, like the ordinar}' tangerine or common orange, can be 
 cultivated only in Florida and California, where citrus fruits are 
 ordinarily grown. They are unhesitatingly recommended for further 
 testing and cultivation in these sections. 
 
SB 369 
 .W35 
 Copy 1 
 
 / 
 
r