Sudan Grass. 17 Several facts in regard to prussic-acid poisoning should be kept in mind by the grower of Sudan grass.

(1) The formation of prussic acid is most frequent in Sudan grass that has been injured by drought or other unfavorable climatic conditions.

(2) Hogs can be pastured on Sudan grass in safety, and horses and sheep are less susceptible to the poison than cattle.

(3) No case of Sudan grass poisoning has been reported from the Southern States or east of the ninety-eighth meridian. North of Oklahoma and west of the ninety-eighth meridian care must be exercised in pasturing Sudan grass with cattle.

(4) The poison acts quickly, and no sure remedy for it has been found. Doses of glucose or other sweet sirups relieve the animal in some cases. Soda and dilute vinegar used as a drench while the mixture is foaming have also been recommended.

SEED PRODUCTION.

Sudan grass produces seed freely in a loose, open panicle which is held nearly erect by the stem and can be harvested easily. The seed is retained fairly well, and thus the loss from shattering is much less than in other wild forms of sorghum. However, on the Great Plains, high winds sometimes shatter out a large percentage of the seed.

At the present time most of the commercial Sudan grass seed is produced in Texas, Oklahoma, and Kansas, but western Missouri and eastern Colorado and New Mexico also produce more seed than is needed for local consumption. Seed yields per acre are largest in the irrigated regions of California and Arizona, but only limited acreages are devoted to Sudan grass in these localities because of the profitable returns from other crops. The yields of seed per acre obtained in different sections of the United States are shown in Table 2.

TABLE 2.—Yields of Sudan grass seed under different climatic conditions in cuh tivated rows and close drills.

Climatic conditions.

Yield of seed per acre (pounds).

Broadcast or close drills Cultivated rows 18 to 24 inches apart.

Cultivated rows 36 to 44 inches apart.

Number of localities.1 Humid Dry (not irrigated) Dry (irrigated) 328 206 1,123 417 285 354 271 905 10 12 7 i The yields for the humid regions are averages for tests at Manhattan, Kans.; Stillwater, Okla.; Beeville and Temple, Tex.; Jackson, Tenn.; St. Paul, Minn.; Madison, Wis.; College Park, Md.; and Arlington Farm and Blacksburg, Va.; for dry regions not irrigated, averages of tests at Colby, Hays, Tribune, Garden City, and Dodge City, Kans.; Chillicothe, Spur, Lubbock, Amarillo, and Dalhart, Tex.; Ritzville and Wenatchee, Wash.; and Davis, Calif.; for dry regions irrigated, averages of tests at San Antonio, Tex., Phoenix, Ariz.; Bard, Davis, and Chico, Calif.; and Umatilla, Oreg.

These yields represent rather accurately the possibilities of seed production in different parts of the United States. Of course, certain localities are better suited to seed production than others. In Lubbock, Crosby, Floyd, Hale, and Swisher Counties in Texas the seed yields average about 600 pounds per acre for Sudan grass planted in rows, as compared with an average for the entire nonirrigated lands in the dry regions of only 270 pounds per acre. After