FIELD CROPS 483 



or sandy-loam soil will generally prove more satisfactory, particu- 

 larly if it is well filled with humus, so that its moisture-holding 

 capacity is high. Good drainage is essential, however, as winter- 

 killing is most likely to occur on poorly drained land. Rust and 

 other diseases are also most severe on low, poorly drained areas. 



Barnyard manure is not usually available in sufficient quan- 

 tity to be much of a factor in keeping up the fertility of the soil. 



The best and cheapest method of adding nitrogen is by grow- 

 ing a green-manure crop, which gathers nitrogen from the air and 

 stores it in the soil. Green manures also supply humus or vegetable 

 matter, which is usually lacking in southern soils. 



Barnyard manure is an excellent fertilizer for almost all crops, 

 as it contains all the elements of plant food and a considerable 

 quantity of humus as well. One of the best methods of using barn- 

 yard manure on oats in the South, where it is seldom available in 

 large quantities, is as a top-dressing applied in the late fall or early 

 winter. When so applied it serves as a protection to the crop during 

 the winter and at the same time adds fertility to the soil. It is 

 probable that the largest increase to the ton of manure will result 

 from the application of about 5 tons to the acre. 



If nitrogen has been supplied in liberal quantities through 

 the growth of legumes as green manures, it need not be added in 

 commercial fertilizers. If, however, a green-manure crop does not 

 immediately precede the oats, or if the preceding crop was light, 

 some readily available fertilizer carrying nitrogen (ammonia) 

 should be used. The best results on most classes of soil are to be 

 obtained by adding this nitrogen as a top-dressing in the spring, 

 about two months before harvest. The nitrate should be sown 

 broadcast and worked into the soil with a harrow. Cottonseed meal 

 or dried blood may be used to supplement the nitrate of soda. On 

 sandy soils the application of about 25 pounds of nitrogen (50 

 pounds of nitrate of soda and 200 pounds of cottonseed meal or 100 

 pounds of dried blood) to the acre is recommended. 



On clay soils this may be reduced to 18 or '20 pounds of nitro- 

 gen (30 pounds of nitrate of soda and about 150 pounds of cotton- 

 seed meal). If the oats are grown for hay, more nitrogen should 

 be used than when they are grown for grain. 



Rotation. The most common cultivated crops in the South 

 are cotton and corn, and as corn is removed from the land earlier 

 than cotton, oats usually follow the former. One of the best rota- 

 tions which can be devised for the cotton-growing section is as fol- 

 lows: First year, cotton; second year, corn, with cowpeas planted 

 at the last cultivation ; third year, winter oats, followed by cowpeas. 



Outside the cotton-growing section a good rotation, including 

 oats, is as follows: First year, corn, with cowpeas in the corn; 

 second year, oats, with clover or grass seeded in the oats ; third year, 

 meadow or pasture. 



If it is desired to grow wheat, oats may be sown after the corn 

 and cowpeas planted after the oats are harvested. Wheat may then 

 be planted after the cowpeas and grass seeded with it. Potatoes 



