besides giving a good yield of grain per acre. Almost all varieties are spring grown. Of other countries emmer is chiefly cultivated in Russia, Germany, Spain, Italy and Servia, and to some extent in France. The emmer of this country is descended from seed originally obtained chiefly from Russia, where a considerable portion of the food of the Volga region is a sort of gruel (“kasha") made from hulled and cracked emmer.

"The desirable qualities furnished by this group of wheats are:

(1) Power of holding the grain in the head.

(2) Drought resistance.

(3) Resistance to orange leaf rust.

"The undesirable qualities are:

(1) Brittleness of the head.

(2) Adaptability only for spring sowing."1

81. Common Wheat (Tr. sat. vulgare Hackel).—As the name implies, this is the subspecies commonly grown throughout the wheat growing districts of the world. Its high yielding power and its excellence for breadmaking are the special qualities which have made it the leading cultivated sort.

82. Club or Square Head Wheat (Tr. sat. compactum Hackel).-This subspecies differs from common wheat principally in the shortness and compactness of the head and the shortness (usually about two feet) and stiffness of the straw. It is less liable to shatter before or during harvest and less liable to lodge than common wheat, and is thus especially adapted to the Pacific Coast States and those Rocky Mountain States where the wheat stands on the field for some time after it is ripe and is cut with combined header and thresher. Aside from the regions named it is cultivated chiefly in Chile, Turkestan and Abyssinia. There are both spring and winter varieties. The latter are adapted only to comparatively mild climates. The quality of the grain does not differ materially from that of the softer varieties of common wheat.

Club wheat. (One-half natural size.)

1 The Basis for the Improvement of American Wheats. By M. A. Carleton U.S. Dept. of Agr., Div. of Veg. Phys. and Path. Bul. 24 (1900), pp. 34-35.

83. Poulard Wheat (Tr. sat. turgidum Hackel).—This sub species is not grown in this country except in an experimental way. It is grown chiefly in the hot dry regions bordering the Mediterranean and Black Seas. It is frequently called English wheat, although it is not grown in England. It is so closely allied to durum wheat as to be hardly distinguished from it, especially in some varieties. It differs chiefly in having a broader spike, shorter beards, shorter and less dense grains and stiffer straw. Some varieties of this subspecies have branching spikes and are known as Egyptian wheat or the wheat of miracle (Tr. compositum L.). Tr. compositum is simply a sport and is of no value.

84. Durum Wheat (Tr. sat. durum Hackel).-The varieties of this subspecies are commonly referred to in this country as

macaroni wheat, because they have been principally used in Europe for the manu facture of semolina, the manufactured material from which macaroni and other forms of edible pastes are produced. Durum wheat is superior to common wheat for this purpose on account of its higher gluten content and Station has shown that

greater density. The South Dakota bread of fine flavor with a dark color somewhat resembling rye bread can be made from it. Millers generally avoid buying it for ordinary bread flour. It is hoped that the manufacture of macaroni may be stimulated in this country, which it is believed would increase its use, because freshness is an important

attribute of high class macaroni. Heretofore most of the macaroni has been imported, the domestic article not having been altogether satisfactory. This has been due in part, it is believed, to lack of good macaroni wheat and in part to lack of technical skill in the manufacture of the semolina.1

"The macaroni wheats are tall,

with broad, smooth leaves. The heads are heavily bearded, being much more so than any of the ordinary wheats, and the plant when bearded has much the appearance of barley. The heads are large and vary in color from light yellow to almost black, depending upon the variety. The kernels are large, very hard, having less starch than common wheat. They vary from light yellow to reddish yellow in color. The habits of growth of durum wheats adapt them to regions of light rainfall. They have great ability to withstand drouth and heat but require a rich soil, although they are notably tolerant of alkali. In some mild climates durum wheats are sown in the fall, but generally they are grown as spring wheat." 2

The natural habitat of durum wheat is about the same as that of poulard wheat. In Spain it is more largely grown than any other type. It is also grown considerably in Southand Central America,

Durum wheat.
(One-half natural size.)

whence it has found its way into Texas under the name of Nicaragua wheat. Another variety has been grown successfully in parts of the Northwest and Canada under the name of Wild Goose. The varieties of durum wheat tested at the stations have

1 Manufacture of Semolina and Macaroni. U. S. Dept. of Agr., Bu. of Pl. Ind Bul. 20.

2 Neb. Bul. 78, p. 4.

come principally from Russia and Algeria. The former seem to be superior to the latter, which suggests that the best results will be obtained in more northerly portions of the semiarid section of this country.

The durum wheat does not tiller as freely as common wheat. The South Dakota Station recommends six pecks of seed where five pecks of common wheat are used. Otherwise the culture of durum wheat is similar to that of common wheat.

85. Polish Wheat (Tr. polonicum L).—This species may be distinguished from the common varieties of wheat by the palea of the lowest flower, which is half as long as the flowering glume,

Polish wheat.

(One-half natural size.)

while in the latter the palea is as long as its glume. In the polish wheat the outer glumes are as long or longer than any of the flowering glumes, while in the common varieties the outer glumes are shorter. The grains of polish wheat are large and somewhat resemble rye, which accounts for the wheat being sometimes called Giant or Jerusalem rye. The glumes are blue-green, the spikelets rather long, close to rachis, giving spike a striking appearance. This wheat is cultivated somewhat in southern Europe, but is ordinarily not considered productive. It is believed by Carleton to be adapted to the arid districts of this country. It is adapted for the production of macaroni but not for breadmaking.

86.

Spring and Winter Wheat.-There are spring and winter varieties of all the species and subspecies of wheat except emmer, which is a spring variety only. Linnaeus divided common wheat into two separate species, calling winter wheat Tr. hybernum and spring wheat Tr. oestivum. It has been shown, however, by direct experiment that winter wheat may be changed to spring wheat

and spring wheat to winter wheat. M. Mouries sowed winter wheat in the spring and out of one hundred plants four alone ripened seeds. These were sown and resown and in three years plants were reared which ripened all their seeds. Conversely, nearly all the plants raised from spring wheat sown in the autumn perished from the cold, but a few were saved and produced seed. In three years this spring variety was converted into a winter variety. This is a striking example of the climatic adaptability of wheat. It shows that a variety which possesses valuable characteristics, although lacking hardiness, may be worth attempting to grow, provided intelligent selection is exercised until it becomes adapted to the climate.

87. The Importance of Variety.—The variety has much to do with the successful culture of wheat 'n each individual instance. Except in the possible extra outlay for seed, it costs no more to raise twenty bushels from a good variety than fifteen bushels from a poor variety. If, on the other hand, the yield is increased by the use of fertilizers or by better preparation of the seed bed, the increase is made at some expense, more or less considerable. (29)

88. The Best Variety.-There is no best variety for the whole country. Not only do good varieties in one locality prove poor varieties in another, but sometimes a variety which one year gives the largest yield of fifty varieties, sown the next year in the same locality is one of the poorest yielders. Nevertheless, careful and systematic tests covering a decade or more by several experiment stations show that certain varieties are on an average of years decidedly superior to other varieties in the given locality and for the particular soil and methods of culture. Hays estimates that the Minnesota Station has made possible the increase in the yield of wheat in Minnesota one to two bushels per acre, or five to ten per cent, through the introduc