TiTK Yi-.MA Mksa 261 



FIELD CROPS ON THE YUMA MESA 



Field crops growing under virgin soil conditions were com- 

 pared with crops growing on land that has been under cultivation 

 for upwards of twenty years. All improved farms of the Mesa 

 were visited, and their condition noted. The native vegetation of 

 the Yuma Mesa also was observed and examined as an indication 

 of the natural productiveness of the soil. Much information re- 

 garding the results secured in the growing of field crops upon the 

 Mesa was secured from old residents of the vicinity. 



The chemical and mechanical analysis of the Mesa soils are 

 reported upon in another section of this report, and will not be 

 discussed here. It is sufficient to say that the total amount of 

 plant food is relatively low, but the available amount relatively 

 high, consequently when water is supplied in sufificient quantities, 

 crops adapted to the climate of the Yuma Mesa may be expected 

 to grow and produce in a satisfactory manner. The soil is deficient 

 in organic matter, and also in nitrogen. As stated elsewhere in 

 this report, the irrigation water from the Colorado River carries 

 considerable nitrogen and a very heavy deposit of silt. For this 

 reason irrigation will build up these soils and the longer they are 

 held under cultivation and irrigated with water from the Colorado 

 River, the more productive they should become, provided green 

 manure crops are sufficiently utilized and a well regulated crop- 

 ping system followed. 



On the Mesa lands near the Blaisdell Orchard in 1918 there 

 was a field of cotton of approximately 10 acres, on land said to be, 

 and appearing to be, virgin soil. This field was not uniform in 

 growth, but taken on the average it was a very creditable field and 

 was estimated by competent parties to yield approximately one- 

 half bale of short staple cotton per acre. Examination of the field 

 showed that it had not been supplied with sufficient water, as the 

 portions of the field along the irrigation ditches, and the portions 

 toward the lower side of the field, showed a more rank growth ot 

 cotton stalk and a greater quantity of lint. See Figure 20. 



In another field near this same orchard, milo was grown in 

 1918 on soil that had previously grown one other crop. This field 

 likewise suffered from lack of water, and the stand was very thick, 

 but even with these handicaps, the milo made a creditable forage 

 growth. The yield of grain was light. 



Reliable parties report that in previous times barley, oats, and 

 wheat have been grown with more or less success, but, mainly due 

 to the high irrigating costs, they were seldom profitable. It is 



