GROWING GRAIN CROPS IN DRY AREAS 221 



light showers fall frequently and at short intervals, the 

 land will not form cracks or openings so numerously as 

 after a heavy rain. 



The fallow land must also be kept clean. This is 

 imperative, as in proportion to the extent to which 

 weeds grow on the land, just in that proportion will 

 moisture be taken from the soil. Weeds will draw on 

 moisture more heavily than grain plants because of their 

 stronger inherent powers of growth. Should moisture 

 be conserved during the early part of the fallowing proc- 

 ess, and weeds are then allowed later to grow on the 

 same, the weeds will remove the moisture thus conserved, 

 and will thus so far undo what has been done. To pre- 

 vent such a result, it may be necessary to use the nar- 

 row more frequently than would be necessary for renew- 

 ing the dust mulch to. prevent the escape of moisture. 

 Annual and biennial weeds may be most easily destroyed 

 when they are just beginning to grow. But the use of 

 other implements may be necessary in order to destroy 

 perennial weeds and volunteer grains that have become 

 deeply rooted (see p. 120). 



When the bare-fallow has been managed thus, in 

 nearly all instances, there will be moisture enough in the 

 same to germinate winter wheat when sown on fallow 

 land, even in very dry seasons. But to this there may be 

 some exceptions, as when the ground is lacking in mois- 

 ture in the spring when it is plowed, and when no mois- 

 ture virtually falls on it subsequently. Such was the 

 condition of fallow land in the spring and autumn of 

 1910. In numerous instances, when the winter wheat 

 was planted it did not germinate. But this will seldom 

 occur. 



When wheat follows a cultivated crop, the treatment 

 of the land that is best suited to the needs of the culti- 

 vated crop will also be best suited to the needs of the 

 wheat crop that follows. The cultivated crop that may be 



