128 GARDEN FARMING 



better suited to them than are the heavy clays. The growth of 

 the vine is too much restricted upon very heavy clayey soils, and 

 although the vines yield well in proportion to their growth, the 

 total product is in proportion to the growth of the plant as a whole. 

 Figure 41 shows a typical bean field in the North. 



Preparation of the soil for field beans. The bean is a warm- 

 season crop and cannot be safely planted until after danger from 

 killing frost has passed. The preparation of the soil for field beans 



FIG. 41. A typical bean field in the North 



should be deferred until the vegetation covering the area has made 

 considerable growth, so that it may be as completely destroyed as 

 possible during the operation of plowing, harrowing, and fitting 

 the land for the reception of the seed. The short season required 

 by beans permits using the land during the winter months for some 

 cover crop, such as wheat or rye ; and if the same land is used year 

 after year for the production of beans, the turning under of winter 

 cover crops furnishes an important means by which the store of or- 

 ganic matter in the soil can be maintained, a consideration of impor- 

 tance in sections chiefly dependent upon commercial fertilizers. 



