ê Farmers' Bulletin 1126.

sorghum, or millet. Notwithstanding this indicated high water requirement, Sudan grass has been successfully grown as a dry-land crop since 1912, when the first wide distribution of seed took place. As an emergency hay crop and summer pasture no other crop is better suited to conditions in the southern half of the Great Plains.

On the university farm at Davis, Calif., it has been grown with good results as a dry-land crop and is recommended for use in other parts of that State where irrigation water is not available.3 SOIL REQUIREMENTS.

Sudan grass is not at all exacting in its soil requirements. It does best on a rich loam, but it has been grown successfully on almost every class of soil from a heavy clay to a light sand. Where the soil is quite sandy, however, the yield may be expected to be light.

Cold, wet, muggy soils are particularly unsuited to Sudan grass. Before such soils will grow it, thorough drainage must be provided. Small amounts of alkali in the soil reduce the yields markedly and stronger concentrations prevent profitable culture.

PLACE IN THE CROPPING SYSTEM.

Although Sudan grass is an annual and can be introduced easily into any rotation, it probably never will be widely used as a staple crop in permanent rotations. To fill such a position acceptably a crop must serve either as a " money crop " or as a soil improver. Under certain conditions in the Southern States Sudan grass utilized as a hay crop or for seed production may be considered as a cash crop, but in most cases it will be grown as an emergency hay crop or for summer pasture.

The other two crops most widely grown as catch crops or emergency hay crops are millet and sorgo, or " cane " (fig. 4). The yields of Sudan grass, as compared with these two, its chief competitors, over a series of years from 1912 to 1919 and at a considerable number of stations are given in Table 1.

TABLE 1.—Comparison of Sudan grass with millet and sorgo in yields per acre of cured hay.

Yield per acre (tons).

Region.

Sudan grass. Millet. Sorgo.

Northern Great Plains ___ 1.49 1.78 3.33 2.80 1.89 1.51 1.83 2.52 2 24 Central Great Plains _ 2 89 Southern Great Plains.— . _. _ 4 64 Timothy and clover belt _ _ _._ 6.06 It will be seen that in the northern Great Plains Sudan grass is less productive than millet. In the central Great Plains and the timothy and clover belt Sudan grass shows an average hay yield of about one-fourth ton per acre greater than the yield of millet, while »Madson, B. A., and P. B. Kennedy. Calif. Agr. Bxp. Sta. Bui. 277, p. 200. 1917.