CULTURE OUTSIDE CORN BELT I87 



from those required for the best results in a humid 

 climate. For nearly all of the irrigated region, fall 

 plowing is preferred, not only because it gives a better 

 opportunity for weathering and disintegration during 

 the winter, but also because the soil particles have an 

 opportunity to settle together and pack sufficiently for 

 quick capillary attraction and to^ prevent too free cir- 

 culation of the air to deprive it of moisture. The 

 spring plowing is too loose and open for best results, 

 giving it an opportunity to dry out too fast, and leav- 

 ing insufficient moisture for germinating the seed. The 

 deep plowing is also desirable to afford a reservoir to 

 hold the winter and spring precipitation, and increase 

 the depth to which roots may readily penetrate for food 

 and moisture. 



The same early surface cultivation in the spring 

 is as desirable as in other methods of com growing to 

 destroy the weeds just as soon as they have started, 

 and to establish a soil mulch to prevent the loss of 

 moisture by evaporation. The same rules govern as to 

 the time of planting, that is, when the season is ad- 

 vanced sufficiently to warm up the soil enough to start 

 the seed promptly after it is put into the ground. For 

 irrigation, the land needs some additional preparation. 

 The field should be graded to an even slope in order 

 that the water may pass freely over it. Knolls and 

 ridges must be leveled down^ holes and depressions 

 filled up and dead furrows eliminated. The frequent 

 cultivation with a harrow or a weeder from the time 

 of planting until the corn is too large for this method 

 of tillage is essential also to kill the weeds, to renew the 

 soil mulch and to keep the land in a proper condition 

 of tilth. 



Irrigation — Irrigation should be deferred until 

 the com shows the need of it. This is usually deter- 

 tnmed by its very dark color, or by its wilting slightly 



