CHEMICAL COMPOSITION The average of a number of analyses made at different places gives the soy bean plant as a whole about the same composition as the cowpea plant. The seed of the soy bean is, however, much richer than that of the cowpea in the two most important constituents, protein and oil (fat). Analyses of the seed of some of the varieties grown at the Station farm and also of soy bean and cowpea straw, and of corn stover, all of which were grown in the same season and under like conditions, were carefully made by Mr. W. E. Grainger, and are given in Table X. According to these results the soy bean plant is richer than the cowpea plant in both protein and oil. A thorough study of the question is now being made in the Station laboratory. TABLE X-Analyses of soy bean seed, etc.-crops of 1906 and 1907 Per cent fresh or air-dry material Per cent water-free substance As the result of an appropriation made by the State Legislature of 1907 for cooperative experiments in Middle Tennessee, soy beans, among other crops, were grown in a number of counties. In a brief general report, however, the three sections-the Central Basin, the Highland Rim, and the Cumberland Plateau-should receive attention rather than the individual counties. This is especially advisable as each section is, from an agricultural point of view, sharply defined, and also because a county may have more than one of those sections represented in its borders. THE CENTRAL BASIN From observations on numerous farms in the Central Basin where soy beans were being grown experimentally, and from the experience of a few farmers who have grown them more or less extensively, there seems to be no doubt of their adaptability, not only to the soils but also to the type of farming generally practiced. The cowpea has been grown for a number of years, but the uncertainty of this crop as a grain producer is especially marked in this naturally very fertile part of the State. There is apparently no reason why the soy bean should not do as well here as at the Experiment Station farm, provided, of course, that similar culture be given; hence, the results reported in the body of the bulletin are believed to apply with special fitness to this area. POLE FRAME THE HIGHLAND RIM During the seasons of 1907 and 1908 trials of soy beans, and of cowpeas for comparison, both with and without fertilizers, were made on the two general types of soil found on the Highland Rim. The yields indicate that the soy bean is a valuable crop for this area, and that under good methods of farming, aided by the judicious use of commercial fertilizers, yields rivaling those obtained anywhere in the State may be obtained. In fact, the highest yield from any of the cooperative experiments was obtained with the aid of fertilizer on the gray-colored soil of the Barrens type at Tullahoma, but this particular soil must be looked upon as decidedly above the average of that section. Although the red limestone soil is naturally stronger and more durable under cultivation than the gray soil derived from siliceous, or freestone, rock, both kinds are deficient in phosphate and responded read ily to either acid phosphate or bone meal. In a few instances the gray soils responded to potash in addition. As a general formula for either soy beans or cowpeas the following is recommended: Acid phosphate or Muriate of potash 300 pounds 25 pounds Where neither wood ashes nor the muriate of potash is to be had acid phosphate alone may be used to great advantage-200-300 pounds per acre being considered a fair application-and should be well worked into the rows before planting. Wood ashes in the quantity recommended in the formula are superior to the muriate of potash, for they contain on the average 30-40 per cent of lime, and also some phosphoric acid, in addition to about 5 per cent of water-soluble potash. SOY BEAN HAY CURED ON FRAME THE CUMBERLAND PLATEAU Of all the soils tested, the sandy loams of the Plateau seemed, when properly fertilized, best suited to the soy bean, and in addition the climate of this elevated section is favorable. Mr. J. E. Converse, who had charge of the experiments, says in his report: "The soy bean as a crop for the Cumberland Plateau is in a class to itself. It stands farther ahead of its nearest competitor, the cowpea, here than at lower altitudes, in part, at least, because the cool nights on the mountain are detrimental to the growth of the cowpea." The soy bean is especially needed in this section as a reinforcement to the corn, sorghum and millet grown for hay, and also as a supplemental feed for hogs. The same fertilizers are recommended here as for the Highland Rim, but attention is called to the fact that the Plateau soils are frequently in great need of lime. The most acid soils analyzed by the Station have come from poorly-drained areas, with dark-colored humus and nitrogen-rich soils on the Plateau. Some of these soils will produce scarcely any of the cultivated crops until heavily limed, and should be drained to get permanent improvement. They are, moreover, deficient in phosphoric acid, and perhaps in potash, though this last matter has not been determined by direct experiment. On the well-drained Plateau soils, however, this crop grows magnificently with the help of phosphate alone. In Table XI attention is called to the specially high yields of the Mammoth Yellow variety. |