232 FIELD CROPS FOR THE COTTON-BELT 



by-products of this decomposition will have made soluble 

 much of the native plant-food in the soil. The added hu- 

 mus benefits the structure of the soil, increasing its water- 

 holding capacity. 



Loose sandy soils, if plowed in the fall, will suffer con- 

 siderable loss from leaching during the winter months. 

 This is especially true if the land is left bare. Such soils 

 should not be plowed until late winter or early spring. 

 It is not advisable, however, to defer plowing until immedi- 

 ately before planting as the seed-bed will be too, loose for 

 best results. 



It is often impossible to plow land in season, owing to 

 unfavorable weather conditions. Land should never be 

 plowed when wet enough to prevent proper pulverizing. 



281. Depth of plowing. — This must be governed 

 by the character of the soil, its previous treatment, and 

 the time at which the plowing is done. In general, clay 

 soils should be plowed deeper than sands. A very heavy 

 clay soil should be plowed deep at least once each year. 

 Soils of medium texture may produce satisfactorily with 

 deep plowing every two or three years. The practice of 

 deepening clay soils should be gone about cautiously. 

 Plowing up large quantities of inert subsoil at one opera- 

 tion will temporarily decrease productiveness. The in- 

 crease in depth should be secured gradually by ploVing 

 an inch deeper each year until the desired depth has been 

 reached. For best results all land should be occasionally 

 plowed 8 to 10 inches deep. 



The earlier in the season at which plowing is done and 

 the greater the amount of vegetable matter to be plowed 

 under, the greater is the increase in depth that can be 

 secured without experiencing any ill effects, 



282. Covering rubbish. — An important object of 



