CHAPTER X 

 SOIL RELATIONS 



SOIL in this connection is considered as a part of the 

 cereal environment. Soil fertility will be discussed in 

 other chapters. 



244. Favorable soil environment. It is sometimes 

 said that any soil will produce good cereal crops if there 

 is plenty of water. But many very sandy soils are not 

 at all suitable for the small grains, though they may be 

 good for maize, sorghums, and legumes. Also, while 

 certain substances are necessary as foods for all plants in 

 common, the kinds most needed, and amounts of each, 

 vary for different crops. 



It has been found that the roots of cereal plants extend 

 ordinarily to a maximum depth of 40 to 50 inches, though 

 extreme cases are known where they have reached a depth 

 of 7 feet or more (see 30 and Fig. 10). The feeding range 

 of cereal roots is therefore usually within the first 5 feet of 

 soil. The small cereals are also short-lived, the period 

 of growth being commonly from 90 to 110 days, or a 

 little less for barley. It seems, then, for best cereal pro- 

 duction, there must be adequate water and mineral food 

 furnished to the plant within about 5 feet of soil, in 

 three to three and one half months* time. Even the few 

 winter cereals are in an inert condition during the winter, 

 and are dependent, largely, on the following summer 

 rains. 



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