TILLAGE 



aration of a seed-bed more frequently than thin 

 soils, and yet it is the latter that may profit most 

 by having its best part kept near the surface at 

 the time a new sod must be made. The disk 

 harrow has some place as a substitute for a plow, 

 but when its use results in making a soil more 

 shallow, the harm is a most serious one. 



Cultivation of Plants. If a soil would remain 

 mellow throughout the season, there usually 

 would be no reason to disturb the roots of plants 

 by any deep stirring, and all tillage would be only 

 deep enough to make a mulch of earth for the re- 

 tention of moisture and to destroy all weeds. 

 Soils containing enough clay to make them re- 

 tentive of moisture become too compact when 

 rains beat upon the ground, as usually happens 

 after the planting of spring crops. A deep and 

 close cultivation of corn and potato plants after 

 they appear in the row helps to restore the con- 

 dition created by the plow and harrow, and often 

 is the best practice. There is some sacrifice of 

 roots, but the gain far exceeds the loss. It may 

 be necessary to give a second such cultivation 

 when a clay soil is deficient in organic matter, 

 but the root-pruning is a handicap. 



Controlling Root-growth. The exception to 

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