FOR BETTER CROPS IN THE SOUTH 83 



although some polish is manufactured into vegetable ivory used 

 in buttons and other articles. The polish sells for about $20 and 

 the bran for $15 per ton. Rice polish makes a splendid stock 

 feed, especially for young animals; in this respect it will com- 

 pare favorably with wheat bran. The bran is a good feed if 

 used fresh, or if it is heated to the temperature of live steam as 

 soon as it is made. Unless this is done, the oils break down 

 rapidly into the corresponding fatty acids, which impairs the 

 digestibility of the feed. This decomposition is due to an enzyme 

 called lipase, which does not develop when the material is heated. 



The History of Rice Growing in the South — Its history is 

 similar to that of wheat growing in the West, or the crop 

 industry of any other country where one crop is peculiarly 

 adapted to the soil and climate. Rice is profitable, and it is a 

 crop that is reasonably certain when the irrigation water can be 

 controlled. As a consequence, rice has been grown year after 

 year on the same land without any effort to keep up the fertility 

 of the soil. As a consequence yields per acre were reduced and 

 it became necessary to practice some crop rotation in order to 

 build up the soil and permit the land to rest. More attention 

 is being given to livestock and to the utilization of farm 

 manures. Drains are being opened and the land prepared for 

 corn, sorghum, peas, potatoes, and other crops. Oats are planted 

 in June and turned under for green manure or pastured down in 

 the fall. Rice or corn follows the peas. Commercial fertilizer 

 is being used in considerable quantities in this section. 



The soils of the rice belt contain an abundance of potash, but 

 are very deficient in phosphorus; the latter, however, can be 

 cheaply supplied in the form of raw rock phosphate. This, how- 

 ever, can be used only in connection with decaying vegetable 

 matter. It should be applied at the rate of 1,000 pounds per 

 acre once every four years. Turning under cowpeas or other 

 legumes will maintain the nitrogen in the soil and render the 

 phosphate of the raw rock available as well as the soil potash, 

 which is in a more or less fixed condition due to continual crop- 

 ping to rice. 



A? J? /? 



