26 



FIELD OPERATIONS OF THE BUREAU OF SOILS, lf>17. 



The (hla fine sand is not extensive. It occurs only in tlie Gila 

 River bottoms from the northeastern end of the area westward to 

 l*.inia Butte. The soil is developed in long;, narrow strips along; the 

 channel of Gila and Little Gila Rivers. 



The soil is well drained in the upper 3 or 4 feet, and in places to a 

 much greater depth, but much of it has a high water table. The 

 texture and structure of the soil being favorable to the capilliary 

 movement of the water, parts of the type contain large quantities of 

 alkali, though tlie areas periodically overflowed do not contain in- 

 jurious amounts. 



The surface is generally level, but not always smooth. Overflows 

 usually leave it in a hummocky or slightly eroded condition, and con- 

 siderable leveling is necessary to fit the land for irrigation. 



Wliere alkali is absent there is a growth of cottonwood and willow. 

 In the alkali areas such plants as seep weed, mescjuite, greasewood, 

 and pickleweed flourish. Alfalfa, cotton, nonsaccharine sorghums, 

 grains, corn, and truck and root crops produce good yields on the 

 well-drained parts of the type, which are free from alkali. Many 

 kinds of tree fruits, the date palm, vegetable crops, and melons are 

 grown at tlie experiment station at Sacaton, and it is likely that some 

 of these crops will be more extensively grown by the farmers. 

 Manures and fertilizers are not Avidely used. 



The results of mechanical analyses of samples of the soil and sul:)- 

 soil of the Gila fine sand are given in the following table : 



Mechanical analyses of Gila fine sand. 



GILA SILTY CLAY LOAM. 



The Gila silty clay loam is a smooth, close-structured, brown, silty 

 clay loam, the color in places having a slightly reddish or choco- 

 late-brown tint. The soil usually extends to a depth of 3 to 6 feet 

 with little change, except that below a depth of 1 or 2 feet the color 

 may be somewhat lighter and the structure somewhat more compact. 

 The surface soil contains a relatively large proportion of organic 

 matter and is distinctly micaceous. The soil and subsoil material is 

 high in lime. In many places the materials forming this type do not 

 appear to be of as recent deposition as those giving the Gila fine sand, 

 but even here the .subsoil has not been cemented or altered by 

 weathering. 



