CONTROL OF SOIL MOISTURE 



The Plank-drag. An excellent implement on a 

 farm is the plank-drag. It is usually made of 

 over-lapping heavy planks, and when floated over 

 the surface, it both pulverizes and packs the soil. 

 The effectiveness is controlled by the weight placed 

 upon it, and oftentimes the drag is to be preferred 

 to the roller. 



The Mulch. In conserving the supply of 

 water in the soil the mulch plays an important 

 work. The dry air is constantly taking up 

 the water from the surface of land, and when the 

 surface is drier than the soil below, the moisture 

 moves upward if there is no break in the structure 

 of the surface soil. The mulch is a covering of 

 material that does not readily permit the escape 

 of water. 



The only available material for a mulch in 

 most instances is the soil itself. Experience 

 has taught that when the top layer of soil, to a 

 depth of two or three inches, is made fine and 

 loose, the water beneath it cannot escape readily. 

 It is partly for this reason that the smoothing- 

 harrow should follow the roller after land has been 

 plowed. The plow is used to break up the soil 

 into crumbs that will permit air to enter. The 

 loosening is excessive when the planting must 



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