CEREAL CULTIVATION EASTERN AREA 315 



other foods, which otherwise would be leached away 

 especially in the summer months or in the winter in the 

 South. 



341. Crops for green-manuring. Rye is a good green- 

 manure crop. It gives good results alone, but is better 

 combined with a legume. Rye is especially suited for 



FIG. 91. Plowing under rye for green-manure in Virginia. 



fall seeding where the land would otherwise remain bare 

 during the winter (Fig. 91). Buckwheat is a valuable 

 green-manure for poor soils, and may be used in the op- 

 posite season from that of rye, during the hot summer 

 months of July and August, preventing the loss of much 

 plant-food which ordinarily occurs at this time. It also 

 adds considerable humus. 



The legumes or nitrogen-gathering crops are the most 

 valuable for green-manuring. They include the clovers, 

 field peas, soybeans, cowpeas, vetches, and sweet clover. 



