8 ' DRY-LAND GKAINS IN THE GREAT BASIN. 



TEMPERATURE. 



The maximum and minimum temperatures are determined daily 

 at the substation from April 1 to October 31. The work was not 

 started until June 1, 1908. The highest temperature recorded in 



1908 was 97.5° F. on August 4; in 1909 the maximum was 99.5° F. on 

 July 3. In 1908 the last spring frost occurred on June 22 (30° F.) and 

 the first autumn frost on August 30 (31° F.). This left a period of only 

 69 days without frost. In 1909 the last spring frost came on May 30 

 (30.5° F.) and the first autumn frost on September 12 (30.5° F.), 

 leaving a period of 105 days free from frost. 



SOIL. 



The soil at the Nephi substation is a heavy clay loam of a red- 

 brown color. It is of a fairly uniform texture to a depth of 6 to- 8 

 feet, where it becomes more sandy. The high percentage of clay 

 (approximately 15 per cent) makes the soil rather difficult to handle, 

 particularly wdien it is very wet or very dry. It puddles readily and 

 great care is necessary to prevent its becoming hard and baked. It 

 resembles a large portion of the soils of the Great Basin area. 



NATIVE VEGETATION. 



One of the most reliable methods of comparing agricultural soils is 

 to compare the vegetation found on them in their virgin condition. 

 Hundreds of thousands of acres of arid land in the West are covered 

 with a heavy growth of sagebrush {Artemisia tridentata) . This was 

 the condition at the substation at the time the land was plowed in 

 1903. In this respect the conditions were typical. (See PI. I, fig. 1.) 



SUMMARY. 



A brief summary of the conditions at the substation, as above 

 described, will assist the farmer in making comparisons. The ele- 

 vation is 6,000 feet; the 12-year average annual rainfall is 14.43 

 inches; the rainfall of April, May, and June during the same period 

 has averaged 4.11 inches; the evaporation for six months, beginning 

 April 1, is about 40 inches; the wind velocity during the season of 



1909 averaged 4 miles per hour and seldom exceeded 8 or 10 miles 

 per hour; the highest temperature during the seasons of 1908 and 

 1909 was 99.5° F. ; there was a 69-day period (June 22 to August 30) 

 without frost in 1908, and a 105-day period (May 30 to September 

 12) without frost in 1909; the soil is a heavy clay loam, which in its 

 virgin condition produces a heavy growth of sagebrush. The con- 

 ditions at Nephi are typical of those existing over large areas in the 

 Mountain States. 



[Cir. 61] 



