THE RANGE RESERVE TRACT. 23 



Receiving as it does a more liberal supply of moisture, the develop- 

 ment is more uniform during the growing season. Even here no sod 

 is formed, indeed no sod could usually be formed if the moisture con- 

 ditions were ever so favorable, for the presence of loose jagged rocks, 

 with the exceedingly rugged conditions, would almost compel the 

 growth of grasses in small bunches. The grasses which form the 

 main feed in such localities, and therefore the most conspicuous of 

 this portion of the vegetation, are Andropogon contortus, A. leiicopo- 

 gon, Trachypogon secundus, EJionurus harbicuhnis, Hilaria sp., 

 Boufeloua hromoides, B. oligostachya, B. curiipendula, Trioda mutica, 

 Eragrosfis lugens, Muhlenberg in grn.cilUnia, J/, pjorferi, Epicampjes 

 rigens, And Arisfida sp. These regions are often so inaccessible that 

 stock can not reach them. They are therefore more nearly primi- 

 tive than the mesas, and one is able to get a better idea of their 

 productivity. 



THE RANGE RESERVE TRACT. 



The range improvement work in Arizona being of a different char- 

 acter from that usually contemplated, and being in a region more com- 

 pletely divested of range grasses than any othei- in the entire country, 

 required considerable careful study in advance to discover the pro^^er 

 locality for experimentation. Accordingly, the greater part of a week 

 was spent in a survey of the surrounding country in the vicinity of Tuc- 

 son for the purpose of determining which of the three typical areas 

 (mesa, foothill, or river bottom) would be the most favorable and give 

 the most conservative and valuable data upon which to base judg- 

 ment of the results obtained by experimentation. Finally a rather 

 favorable mesa area was selected at an altitude of about 2,000 feet 

 above sea level and about 4:00 feet higher than the city of Tucson. 

 This tract, which was subsequently reserved from entry at the request 

 of the Hon. James Wilson, Secretary of Agriculture, is described in the 

 Government surveys as sees. 26, 27, 34, and 35, T. 14 S., R. 14 K., 

 Gila and Salt River meridian. 



Somewhat diagonally through the center of this area runs the South- 

 ern Pacific Railway, and a short distance to the east of it is located 

 AVilmot Siding. The soil is a clay loam, mixed with considerable sand, 

 and subtended at a depth of 2 to 2^ feet by a calcareous hardpan, 

 known among the Mexicans by the significant name ''caliche." Tlie 

 slope, which is rather gentle, has a general northwesterly direction, 

 and is traversed by three more or less distinct, broad, shallow depres- 

 sions, which receive the drainage of a considerable area of land to the 

 southeast. Such a region, with broad, shallow washes, was purposely 

 selected. It was the intention to attemjDt to conserve water flow on the 

 mesa, and to discover what can be done toward preventing "run-off" 

 of water during the rainy season of July and August. Such washes, 

 although the most favorable for the growth of vegetation of all kinds, 



