164 SOILS 



If he cultivates as often as the weeds poke them- 

 selves above ground, which they do with astonish- 

 ing alacrity and in countless numbers after each 

 tillage, he will have established the best kind of a 

 water-saving mulch. This is especially true in a 

 wet May, and most especially true in a muggy, 

 thundery July, when "pusley" starts up from the 

 ground and grows a foot long in a single night, so 

 it seems to our disheartened eyes. But there are 

 times when cultivation is necessary and profitable, 

 when we have few if any weeds to spur us to the 

 exertion. This is apt to be the case during a sum- 

 mer drought when the soil is dried out several 

 inches deep and the weed seeds in the surface soil 

 cannot get moisture enough even to germinate. 

 There are few if any sections of the country where 

 it is not necessary at some time, during an average 

 season, to cultivate for the explicit and sole purpose 

 of preventing the loss of soil water. One season, 

 however, may be so wet that the cultivation that 

 prevents weediness is all that is necessary; the 

 next season may be so dry that the cry of the crop 

 is continuous and loud for more water, rather 

 than for less weeds. 



Signs of the Need of Cultivation to Save Water. 

 It is not difficult to tell when it will pay to cultivate, 

 even when there are not enough weeds to justify it 

 on that score. One has only to examine the sur- 

 face soil. If it is hard, baked, cracked, or even if 

 it has only a thin crust, there is work to be done. 

 Soil water passes off rapidly into the air only so 

 long as the surface soil is compact. If this is 

 loosened the water cannot creep readily from 

 grain to grain, and so is held below the layer of 

 loose soil. 



The first aim of the cultivator, then, especially 



