The Plant as Related to the Soil 



45 



the first effort is to destroy the granular texture, which 

 is done by wetting and working the clay. Puddled 

 clays do not crumble whe,n dried before baking. Neither 

 will a soil puddled by plowing when too wet crumble 

 into fine particles in drying. (See 1 105 and Fig. 40.) 



(b) By exposing the soil to the weathering influences 

 of the air, frost, sun, snow, 

 etc. When a lump or clod of 

 stiff soil is left exposed to 

 the alternate wetting of the 

 rain and drying of the sun, 

 it breaks up into many smaller 

 particles and becomes mel- 

 low. Without this weather- 

 ing effect, much of our plow- 

 ing would be worse than 

 useless. The land often breaks 

 up cloddy, but in time it 

 becomes mellow and loose. 

 (Fig. 29.) It requires time. 

 In order that a soil may be 

 in the best condition for seed- 

 ing, plowing should be done 

 long before planting time so 

 that the weathering influences 

 may have ample time to per- 

 form their work thoroughly. 

 Some soils will weather or 

 crumble promptly, while 

 others, like clay, require more time. Under this head 

 should be included some of the effects following under- 

 drairiage. (See Fig. 41.) The surplus water is thus carried 

 off and air takes its place, and the soil particles crumble. 



Fig. 29. Waiting for time and the 

 rains to mellow down the clods . 



