WHEN TO PLOW, AND HOW DEEP 201 



the effect of plowing. It is the shearing action of the moldboard 

 upon the soil kernels, causing them to divide at the edges of 

 the layers, that makes plowing in tenacious clay or gumbo 

 soils so much harder than in sandy or loamy soils. 



Plowing should be done when most effective. It should be 

 done with reference to the objects desired most, weeds or other 

 vegetation being buried at a time when their growth will be 

 most injured, if that is the principal object; or when the desired 

 texture of the soil may be reestablished, if that is the prime 

 consideration. Extremely dry soils may profitably be broken 

 into lumps of considerable size, for in most sections frost or 

 rain can be depended upon to reduce their size later. This 

 practice is especially good if high winds might cause drifting 

 of too finely divided soil. Fall plowing may well be left rough, 

 in order that snow may be caught to melt into the ground, 

 and frequently a fringe of vegetation left uncovered will assist 

 in catching drifting soil and snow. 



DEPTH OF PLOWING 



The depth of plowing depends largely upon the character 

 of the soil, the climate and the crops to be grown. Channels 

 between the soil kernels are easily formed in sandy soils without 

 plowing; consequently the principal object is often to bury vege- 

 tation. Plowing too deeply may render the soil too porous 

 and hasten the oxidation, or burning out, of organic matter. 

 It is seldom desirable to plow very sandy soils to a depth of more 

 than three or four inches. Very retentive soils devoid of 

 humus, and those containing cementing elements, should be 

 broken to a much greater depth at least every other season. 

 Done at the proper time, and by the proper plow, this soil will 

 be granulated and loosened, thus securing the porous condition 

 favoring plant development. Between these two extremes 

 lies a great range of soil types requiring greater or less depth of 

 plowing. Sod, either wild or tame, is usually broken shallower 



