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T HERE was urgent need for information on cultural methods for castor beans in the early years of World War II when. the increased demands for drying oils with special qualities focused attention on the desirability of domestic production of this crop. Two of the problems investigated cooperatively by theBureau of Plant Industry, Soils, and Agricultural Engineering and many state agricultural experiment stations were the rate and date of planting for those varieties which were used in the program. Mimeographed re-ports3 of all phases of the cooperative work include yearly data on the rate and date tests and list the cooperating stations and individuals. The 1941 to 1943 results of the 35 rate-of-planting tests in 13 states and the 10 date-of-planting tests in 7 states are summarized herein. METHODS AND RESULTS RATE-OF-PLANTING TESTSThe early work on rate of planting has been approached on the basis of a known number of established plants rather than a known amount of seed planted, since the latter would introduce questions of seed viability, depth of planting, emergence, seedling disease, and seed treatment.The 1941 tests were carried to completion at the following 19 locations: Mesa, Ariz.; Bard, Calif.; Quincy, Fla.; Carbondale, Equality, and Mascoutah, Ill.; Maple Hill and Parsons, Kans.; Beltsville, Md. ;· Poplarville, Miss.; Arapaho, Chickasha, and Stillwater, Okla.; and Chillicothe, Deport, Lubbock (2 tests), Robstown, and Scottsville, Texas. It is not feasible to present here the detailed data from these tests since, because of the late date at which the program was started, the tests could not be set up uniformly in regard to design, size, and varieties included.

S EVERAL cultural methods other than rate and date of planting castor beans were studied cooperatively from I94I to I943 3 by the Bureau of Plant Industry, Soils, and Agriculturar Engineering and state agricultural experiment stations. Among them were the use of fertilizers, the method of planting, the clipping or pruning of the growing point, and the time of harvest. Although these tests were conducted on a less extensive scale than the rate-and date-of-planting tests, the results were useful in making recommendations. FERTILIZERSEight fertilizer tests were' conducted, six in I 94 I and two in I 943. The 194I tests were located at Maple Hill and Parsons, Kans.; Arapaho and Stillwater, Okla.; Poplarville, Miss.; and Columbia, Mo. Five of the tests compared fertilizers applied to the Conner variety, while the Poplarville test compared fertilizer placements on the Scott variety (probably a selection from U. S. 4). The work was initiated late in the planting season of 1941, and the tests necessarily lacked uniformity in design and fertilizers used. The treatments and yields are listed in Table I. In view of the usual magnitude of the difference necessary for significance in castor bean tests which are designed to permit statistical analysis, the yield differences between treatments in these tests are not believed to be stifficiently large to be considered significant. Thus, the I94I data indicate that a profitable response would likely not result from application of fertilizers to castor beans, either before planting or as a side dressing after emergence.The two fertilizer tests in I943 were conducted at Lexington and Princeton, Ky. In these tests, which were of uniform design, only the Conner variety was used and nitrogen, phosphorus, and potassium were each applied alone and in all possible combinations at the rate of 2 so pounds of 4-12-8 per acre. Plots were 4 X IO hills in size with single plants spaced 3-SX3-S feet, and only the center two rows were used for yield data. At Princeton the treatments were in quadruplicate and at Lexington they were in duplicate. The yields from these two tests are given in Table 2. The plot at Princeton was rather high in productivity, but _it was thought that the fertilizers used in _this test would have increased corn yields from 5 to 7% for each

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