THE EARTH'S BOUNTY 



slant stirring of the surface soil, to a depth of 

 two or three inches, stimulates growth, because 

 it liberates the constituents of the soil which 

 constitute plant food. Discontinuing cultiva- 

 tion checks growth, and allows that already 

 made to mature sufficiently to withstand win- 

 ter frosts. 



Immediately seeding the ground, after the 

 last cultivation of the season, with rye or 

 buckwheat, holds the soil's fertility by pre- 

 venting leaching, provides a mulch for the 

 winter, and adds humus to the soil when 

 plowed under the following spring. H. P. 

 Gould, assistant pomologist of the Govern- 

 ment Pomological Bureau, explains the neces- 

 sity of tillage and cover crops as follows: 



The use of cover crops in connection with 

 the growing of fruit is closely allied to the 

 fertilizer problem, inasmuch as they are both 

 fundamental factors in soil fertility. 



The producing capacity of the soil is as 

 much dependent upon its physical or me- 

 chanical condition as it is upon the amount of 



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