10 Farmers' Bulletin 1126.
average yields: For Sudan grass and soy beans 2.96 tons, Sudan grass and cowpeas, 2.93 tons, and Sudan grass alone 2.67 tons per
acre. In dry regions such mixtures are not profitable except when irrigated. If there is insufficient soil moisture to support both the Sudan grass and the legume, the grass almost invariably crowds out the legume. The growing of such mixtures should therefore be at- tempted only in humid regions or where irrigation is possible.
CULTURE.
PREPARATION OF THE SEED BED.
In seeding Sudan grass a rather firm seed bed is best. Usually, when it is desired to drill the seed, the ground is plowed in the spring and harrowed well, as for corn. A cool soil delays the germination of the seed ; therefore spring plowing is preferable for the seed bed, because it assists in warming the soil. No fertilizers are necessary in the West, where the soil is reasonably good, but in the East it is probably advisable to use some complete fertilizer, such as. is applied for corn, or some combination of phosphorus and nitrogen, if the price of potash is high. Few experiments have been conducted to determine the best practice to follow, but in Kentucky applications of acid phosphate at the rate of 200 pounds per acre resulted in increases of yield in 8 out of 10 cases. The average increase attrib- uted to the fertilizer was 68 per cent.
DATE OF SEEDING. It has been found best to seed Sudan grass after the soil has become warm, or about two weeks after corn-planting time. When sown in cold soil the result usually is a poor stand or a slow growth for several months, so that in the end no advantage has accrued from the early seeding.
Widely scattered experiments have shown that in very few cases are the earliest seedings highest in hay yield. The experience so far gained by the United States Department of Agriculture in its tests indicates that for the extreme South the best time for seeding lies between April 1 and May 1 ; in the latitude of Oklahoma and Kansas, any time between May 1 and June 15 (Fig. 6) ; and in the latitude of Nebraska and South Dakota between May 15 and June 15. From Kansas south good crops of hay can be secured from seedings made July 1 or even later.
METHOD OF SEEDING.
For hay production in regions of abundant rainfall the best machine for seeding is no doubt the common grain drill. Well-cleaned seed feeds freely from this drill, and it can be distributed evenly and a