CHAPTER VIII. 



CONSERVATION OF SOIL MOISTURE. 



There are very few fields upon which crops of any kind, 

 in any climate, can be brought to maturity with the max- 

 imum yields the soils are capable of producing without 

 adopting means of saving the soil moisture. There are 

 fields, it is true, where, at times, the moisture in the soil 

 is too great, and drainage becomes necessary ; but even un- 

 der these conditions it will usually be found advisable to 

 adopt measures for conserving the water not so removed. 



210. Modes of Controlling Soil Moisture. In aiming to 

 control soil moisture three distinct lines of operation are 

 followed, based upon as many different aims. These are: 



(1) To conserve the moisture already in the soil (a) 

 by different modes, times and frequencies of tillage, (b) 

 by the application of mulches, and (c) by establishing 

 wind breaks. 



(2) To reduce the quantity of water in a soil (a) by 

 frequent stirring, (b) by ridging or firming the surface, 

 (c) by decreasing the water capacity, and (d) by surface 

 or under drainage. 



(3) To increase the amount of water in a soil (a) by 

 increasing its water capacity, (b) by strengthening the 

 capillary movement upward and (c) by irrigation. 



211. Late Fall Plowing to Conserve Moisture There is 



no method of developing so effective a soil mulch as that 

 furnished by a tool which, like the plow, completely cuts 

 off a layer of surface soil and returns it loosely, bottom 

 up, to place again. 



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