TECHNICAL BULLETIN NO. 459 APRIL 1935 CLASSIFICATION OF WHEAT VARIETIES GROWN IN THE UNITED STATES J. ALLEN CLARK Senior Agronomist and B. B. BAYLES Associate Agronomist Division of Cereal Crops and Diseases Bureau of Plant Industry UNITED STATES DEPARTMENT OF AGRICULTURE, WASHINGTON, D. C. i_ u„ 4-UM. Qiincrintftndent of Documents. Washineton. D. C. Price 25 cents Technical Bulletin No. 459 April 1935 UNITED STATES DEPARTMENT OF AGRICULTURE WASHINGTON, D. C. CLASSIFICATION OF WHEAT VARIETIES GROWN IN THE UNITED STATES^ By J. ALLEN CLARK, senior agronomist^ and B. B. BAYLES, associate agronomist, Division of Cereal Crops and Diseases, Bureau of Plant Industry CONT ENTS Page Page Need for classification 1 Classification of the genus Triticum 37 Previous investigations._ _ _. 2 Key to the species or subspecies 38 Foreign classifications , 2 Common wheat.- 39 Domestic classifications 6 Club wheat ____ 128 Summary of previous classifications 8 Spelt .... 135 Present investigations 9 Poulard wheat 136 Classification nurseries 9 Durum wheat 137 Descriptions, histories, and distributions- 11 Emmer -.- 144 Varietal nomenclature. 13 Polish wheat 146 The wheat plant 15 Einkorn 147 Taxonomic characters _ 15 Literature cited 147 Other characters 36 Index to varieties and synonyms 158 NEED FOR CLASSIFICATION The varieties of wheat grown in the united States show a great diversity of type. This diversity is natural, as wheat is produced commercially in most of the 48 States of the Union under a wide range of environmental conditions. More than 200 distinct varieties are grown. Many of these are adapted only locally, while others are well adapted to a wide range of varying conditions. Adaptation of varieties is an important factor, as it affects the yield and profit- ableness of the crop and the standardization of varieties. The choice of varieties for given conditions and purposes is therefore usually given careful consideration by growers. The choice is partly dependent, however, upon the determination of identity. The identification of varieties requires some knowledge of the appearance of plant and kernel and is assisted by information re- garding history or distribution. Wheat varieties are most generally designated by names, which are established through publication and usage. The association of a name with a recognized type of wheat enables identification. Confusion in names is frequent in the United States, where the number of varieties is very large. This confusion occurs in two principal ways: (1) The same name is applied to distinctly different varieties in different parts of the country, and 1 This bulletin is a revision of and supersedes Department Bulletin 1074, Classification of American Wheat Varieties. 81578°—35 1 1 2 TECHNICAL BULLETIN 45 9, U. S. DEPT. OF AGRICULTURE (2) the same variety is grown under several different names in dif- ferent parts of the country or even in the same part. Identification is difficult in cases of similar or closely related varieties and is con- fused by the multiplicity of names. Inability to identify varieties leads to duplication in varietal experiments and the fraudulent or unknowing exploitation of old varieties under new names. There is need, therefore, for a practical and usable system ot classification that will standardize the varietal nomenclature and enable growers to identify varieties with which they are concerned. The purpose of this bulletin is to provide such a classification of the wheat varieties that are grown commercially in the United States or may be so grown soon. The classification has been made by using only such characters as can be distinguished by the naked eye, no instrument other than a measuring rule having been used m the investigations. The names of varieties have been standardized m accordance with a code of nomenclature. PREVIOUS INVESTIGATIONS More systematic study of wheat varieties has been done by foreign investigators than by workers in the United States. FOREIGN CLASSIFICATIONS The existence of many different varieties of wheat has been recog- nized for more than 2,300 years. Theophrastus {207),^ ^ pupil ot Plato, in his Enquiry into Plants, written about 300 B.C., states : There are also many kinds of wheat which take their names simply from the places where they grow, as Libyan, Pontic, Thracian, Assyrian, Egyptian, SicUian They siiow differences in color, size, form, and individual character, and also as regards their capacities in general and especially their value as food. Theophrastus mentioned many of the differences between these kinds of wheat. In the writings of Varro, Pliny, and Columella, in the first century B.C. and the first century A.D., the observations of Theophrastus were repeated, rearranged, and amplified. Colum- ella, who wrote about 55 A.D. (7^, translated 1745), presents these previous observations and his own, as follows : Tritioum, common bare wheat, which has Uttle husk upon it, was, according to Yarro, a name given formerly to all sorts of grain beaten or bruised out of ears by trituration or threshing; but afterwards it was given to a peculiar Ipecies of grain, of which there are many sorts, which take their name from ihe nlaces where they grow ; as African, Pontic, Assyrian, Thracian, Egyptian, ^Llian li^^^^ from one another in'color, bigness, and other prop- ert"oo tedi™o relate. One sort has its ears without beards, and is either of winter or summer. Another sort is armed with long beards, and grows up sometimes with one, sometimes with more ears. Of these the grains are ot different sorts: some of them are white, some reddish, some round, others, oblong some large, others smaU. Some sorts are early ripe, others late m ripening ; some yield a great increase, some are hungry, and yield little; some put forth a great ear, others a smaU. One sort stays long in the hose {folliculo),jin- other frees itself very soon out of it. Some have a small stalk or straw ; others have a thick one, as the AfHcan. Some are clothed with few coats, some with many, as the Thracian. Some grains put forth only one stalk, some many stalks. Some require more, some less time to bring them to maturity. For » Italic numbers in parentheses refer to Literature Cited, p. 147. WHEAT VARIETIES GROWN IN THE UNITED OTATES 3 which reason some are called trimestrian, some Mmestrian; and they say, that, in Euhoea, there is a sort, which may be brought to perfection in 40 days ; but most of these sorts, which ripen in a short time, are light, unfruitful, and yield very little, though they are sweet and agreeable to the taste and of easy digestion. In the early Roman literature mentioned reference is found to two groups of wheat, namely, triticum and adoreum^ or far, Columella referred to the far as bearded wheat. The grain of triticum was separated from the chaff in threshing, while that of far was not, indicating that the former consisted of true wheats, while the latter was emmer or spelt. ^ Columella himself recognized three types of Triticum^ robus (red), siligo (white), and trimestrian (spring), and in addition four types of bearded wheat (spelt or emmer), viz: Clusinian, of a shining, bright, white colour ; a bearded wheat, which is called venuculmn. One sort of it is of a fiery red colour and another sort of it is white ; * * *^ rJ^Y^Q trimestrian seed, or that of 3 months growth, which is called haUcastrum * * *^ It is evident from these quotations that many of the leading char- acters of the wheat plant were recognized in this early period. What attention was given to studies of wheat during the Dark Ages no one can say. With the revival of learning the botanists and medical men began the publication of the folio and royal octavo herbáis, many of them illustrated with woodcuts. In these, wheat species were included, the forms mostly being those described by Theophrastus, Pliny, and Varro, but from time to time new ones were added. There is little advantage in trying to guess what particular form of com- mon wheat each so-called species represented. More recent botanical writers described species that can now be recognized. Principal among these writers was Tournefort (212), who in 1719 listed 14 species of Triticum. The classification of wheat practically began with the work of Linnaeus (Linné) in 1753. In his Species Plantarum {H2) he de- scribed seven species of THticum., viz : T, aestivum^ T, hylernum, T. turgidum^ T, spelta^ T, monococcum^ T. repens^ and T, canimtm. The two latter species have since been included in another genus. In the second edition of the Species Plantarum, published in 1764, he de- scribed six species that are still included in the genus THticum^ viz: T. aestivum^ T, hylemum^ T. turgidum^ T, polonicum^ T, spelta^ and T. monococcum^ the species T. folonicum having been added. Lin- naeus divided the common wheat into two species, T. aestivum^ awned spring, and T. hylernum^ awnless winter, apparently believing that all spring wheats were awned and all winter wheats awnless. Writers who followed him usually have not recognized these dis- tinctions. Lamarck, in 1786 {1S6)^ created the species Triticum sativum to include both the species T, aestivum and T, hylermim that Linnaeus had adopted. Each species and subspecies was described according to the presence or absence of awns, the color and covering of the glumes, the color, size, and density of the kernels, the solidity of the stem, and several other characters. Villars, in 1787 {217), divided the common wheats into two species, Triticum vulgäre and T. tomelle. The latter consisted of awnless wheat having white kernels. 4 TECHNICAL BULLETIN 45 9, U. S. DEPT. OF AGRICULTURE Schrank, in 1789 {186, v. i, pp, 387-389), arranged the cultivated wheats in three species.