CONTROL OF SOIL MOISTURE 



is not needed as an absorbent in the stables its 

 use as a mulch on thin grass lands, or wheat- 

 fields seeded to grass, is more profitable than con- 

 version into manure by rotting in a barnyard. 

 The straw affords protection from the sun, and aids 

 in the conservation of soil water, when scattered 

 evenly in no larger amount than two tons per acre, 

 and a less amount per acre has value. The sod 

 is helped, and as the straw rots, its plant-food goes 

 into the soil. 



Plowing Straw Down. The practice of plowing 

 straw under as a manure is unsafe, when used in 

 any large quantity per acre. It rots slowly, and 

 while lying in the bottom of the furrow it cuts off 

 the rise of water from the subsoil which is a reser- 

 voir of moisture for use during drouth. 



The Summer-fallow. Bare land loses in 

 total plant-food, but may make a temporary 

 gain in available fertility. The practice of leaving 

 a field uncropped for an entire season has been 

 abandoned in good farming regions. Where mois- 

 ture is in scant supply, and a soil is thin, there 

 continue instances of the summer-fallow. In a 

 crop-rotation containing corn and wheat, the 

 corn-stubble land is left unbroken until May or 

 June, and then plowed. In August it is plowed 



[235] 



