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There are several species belonging to different genera of grasses which with sorghum often pass under the name of millet. Such are Choetochloa italica, formerly Setaria italica, Panicum crus-galli, P. colonutn, P. frumentaceum, P. miliaceum, Penisetum spicatum (L.) R. & S. Several of these species have numerous cultivated varieties and numerous common names. Much confusion exists as to their botanical relationships and to the synonyms of the common names. The cultivation of some of these millets is very ancient, and the grain has been used extensively as human food. In the United States these plants are raised chiefly for hay. Canary grass (Phalaris canariensis L.), is raised for bird food, although sometimes in southern Europe for human consumption.
537. The Plant.—The roots of the sorghum plant are said to have strong feeding capacity, which enables the plant to with
stand unfavorable environment. The Kansas Station found that
the roots reach out laterally in all directions from two to six inches from the surface. The culms vary in height with variety, climate, season, soil and culture usually from four to eighteen feet, with greater variations in extreme cases. The culms, like those of maize, are solid. The leaves are abundant, rather thicker and more glossy than in maize. The upper leaf sheath sometimes extends around the lower portion of the head or spike; when in broom corn it is called the " boot."
538. The Inflorescence.—The inflorescence is in a more or less compact spike-like panicle, usually referred to as the head. The different types vary greatly in the form, size, compactness of the head; the usual variations in length being from ten to eighteen inches, except in broom corn, where the " brush " may be twentyeight inches long.
The spikelets are one-flowered, some being sessile and others on pedicels of varying length, usually one of each at each joint of the rachis.
539. The Grain. — The grain varies from other cereals in being more or less round. The color of the grains is variable, white and red being the more common colors. The color resides in the seed coats. The size and shape of the grain vary largely with the type and variety. The grain of Kafir varieties is larger and rounder than sweet sorghum or broom corn varieties.
540. Composition.—Compared with the grain of maize, sorghum seed contains a somewhat smaller percentage of protein and about one-half the percentage of fat. Otherwise they are quite similar in composition. Sorghum fodder is distinctly lower in protein and higher in crude fiber than maize fodder. All varieties of sorghum contain some sugar, varying from two to twenty per cent of the juice, or from 1.2 to twelve per cent of the cane. Those varieties which contain sufficient sugar, say ten per cent, in juice, for the practical manufacture of sirup or sugar are called saccharine or sweet varieties, while other varieties are known as nonsaccharine varieties.
541. Varieties.—Large number of varieties of sweet sorghum have been tested in this country, particularly with reference to their value for the production of sirup and sugar. Among these varieties are two rather well marked types: the amber canes and the orange canes, the former of these being rather more early maturing than the latter. These are also recognized as desirable varieties for forage purposes. Early amber, extra early; Folger's, early; Colman, medium; and Collier, late, are recommended for this purpose as well as for the manufacture of sirup. Among the varieties grown for seed the principal ones are known as Kafir corn, of which three varieties are recognized: red Kafir, white Kafir and black hulled white Kafir (synonym African millet). In the red Kafir the seed is red or light brown, while in the white Kafir the seed is white. The hulls are gray or greenish white, while in the black hulled white Kafir the hulls are gray, brown or black. In both the white varieties the hulls are hairy and larger than in the red variety, where the hulls (glumes) are small, thin and brown, covering less than half the grain. The seed of both white varieties is less astringent and more palatable than the red variety. At the Kansas Station the red and black hulled white varie
A, Sorghum: type, standard broom corn. (After Hartley.) B, Sweet sorghum: variety, amber cane. (After Denton.) C, Kafir corn: variety, black hulled white. (After Georgeson.)
but the culture of the black hulled white variety is being rapidly extended. While the Kafir varieties have the widest adaptation and are most largely grown, durra (synonyms Indian millet, Egyptian corn), milo maize, Jerusalem corn and Egyptian rice corn are also grown, the latter two being especially adapted to higher altitudes and arid regions.
"These are very similar to Kafir-corn In many respects, and in growing, harvesting and feeding practically the same methods may be followed. The white milo maize grows a head very similar to Kafir-corn, is a heavy yielder of fodder, but
ties have given the largest yields; while at the Oklahoma Station the white varieties have given the best results. Up to the present time the red variety has been most generally grown,
requires a full and favorable season for maturing, and is often damaged by frost on this account The yellow milo maize, or 'Brown Dhura,' does not require so long a season, and is a heavy yielder of grain, the head hanging down on a short gooseneck, when ripe. The crooked heads, which hook and cling to everything they touch, are a great hindrance in handling. The seed also shells badly when ripe. Rice-corn and Jerusalem corn are very similar in their growth, the heads of both hanging down, ard annoying in the same way as those of the yellow milo maize. The seed of Jerusalem corn, being slightly flattened when ripe, can be distinguished from that of the rice-corn, which is round and also lighter in color. The two will mature in a short season and produce from twenty-five to fifty bushels of seed. They are adapted to the higher, cooler and drier counties of the western part of the state. They are very productive of seed, but the fodder yield is very light. In the eastern part of the state the English sparrow is a great pest where grain is raised. The seed is somewhat sweeter than the Kafir-corn grain, which they bother very little." 1
Broom corn is divided into two types: the standard and the dwarf. Standard broom corn grows from ten to fifteen feet high, bearing a panicle of brush from eighteen to twenty-eight inches long; while the dwarf grows from four to six feet high and bears a brush of finer quality from ten to eighteen inches long, with occasionally strains that produce brush as long as two feet. The product of the dwarf variety is used for making whisk brooms and other brooms of small size; while that of the standard sort is used for making ordinary carpet brooms. The dwarf varieties have a larger amount of foliage, are better adapted to stand drouth, and for cultivation on sandy soils. Kafir varieties usually grow from four to seven feet in height; while sweet sorghum varieties usually range from eight to ten feet in height .
542. Improvement of Varieties.—The wide variations in the cultivated forms of sorghum suggest that the varieties might be easily improved or modified by selection, provided they are kept from crossing. Hartley has shown that broom corn and sorghum will readily cross and produce intermediate forms when grown in adjacent fields.1 The different forms may become
1 Rpt. Kan. St. Bd. of Agr., March, 1900 p 64. * D. S. Dept. of Agr., Farmers' Bui. 174, p. 12.
injured by such crossing, thus making it desirable to exercise care with regard to the source of seed used for planting. The maintenance of a seed patch grown from seed selected from the best plants of the seed patch of the previous year is to be recommended here, as with other cereals. This is particularly true in the case of broom corn, inasmuch as there is consider- »able variation in the brush of different plants, crooked and thick centered brushes greatly reducing the value of the product. These forms are probably hereditary and, if so, could be eliminated in the course of time by selection, although it would doubtless take some time on account of the influence of crossing. Hartley suggests that it might be possible to produce a saccharine variety of broom corn, thus securing a variety that would produce both broom and sirup. For the production of grain, Kansas prefers long closely compact heads.
543. Germination.—The germinating power of sorghum is very likely to be low, and poor stands are very common because the grain, even though it has been thoroughly dried, is liable to absorb sufficient water in damp weather to produce fermentation. Grain intended for seed should, therefore, be left in the heads until planted. The heads may be either hung up separately or kept in loose piles in a dry, well-aired place. Testing the germination power is important and seed that is less than ninety per cent should not be used.
II. CLIMATE AND SOIL.
544. Climate.—Sorghum is especially adapted to a climate that is both hot and dry.
"Perhaps the strongest recommendation of Kafir corn lies in the fact that it will produce a crop on less rain than is required for corn, and that it is not affected so disastrously by hot winds. It is, therefore, especially adapted to the semiarid West, where corn succeeds only one in five or six years because of hot winds and drought. It is owing chiefly to this quality that its culture has spread so rapidly in Kansas and Oklahoma. Hot winds are the main cause of the failure of the corn crop in this region, and they are never more destructive than when they happen to