DRY-LAXD GRAINS IN THE GREAT BASIN. 19 



DEPTH OF PLOWING AND SUBSOILING. 



The substation in 190S started a test to determine the best depth 

 to plow wheat hind and the vahieof subsoiling. In the fah of 1908 four 

 plats which had produced a crop of wheat that year were treated as 

 follows: 



Plat 16 A, plowed 7 to 10 inches deep with an ordinary plow and subsoiled 



to a depth of 18 inches. 

 Plat 17 A, plowed 7 to 10 inches deep with an ordinary plow and subsoiled 



to a depth of 15 inches. 

 Plat 18 A, plowed 10 inches deep in the ordinary way. 

 Plat 19 A, plowed 5 inches deep in the ordinary way. 



After receiving this treatment these plats were left untouched until 

 April, 1900. From this time they were treated as ordinary fallow 

 plats and were planted to winter wheat in the fall. 



The moisture content of each plat was determined at three periods 

 during the season, viz, April 6, July 28, and September 23. No very 

 great differences were noted in the moisture of the four plats, although 

 the two subsoil plats contained slightly more water on July 28 than did 

 the plats that were plowed to depths of 5 inches and 10 inches, respec- 

 tively. It will require several years to determine with certainty 

 the relative values of the various treatments. In 1910, while the 

 plats named above are producing a crop of wheat four other plats 

 which were plowed and subsoiled in the fall of 1909 will lie fallow 

 and will receive the same treatment that plats 16 A, 17 A, 18 A, 

 and 19 A received in 1909. By growing wheat crops on the variously 

 treated plats and by making moisture determinations from time to 

 time it will be possible to study the effects of the treatments very 

 satisfactorily. 



The most successful practice at present on the dry lands is to plow 

 to a de])th of from 7 to 10 inches. There have been instances where 

 plowing deeper than 10 inches and even subsoiling to a depth of 

 15 to 18 inches have given profitable returns, but until the actual 

 results of these methods are scientifically determined, as contem- 

 plated by the test at the substation, plowing 7 to 10 inches deep is 

 recommended. 



CARE OF FALT^OW SOIL. 

 OBJECTS. 



The ])rincipal objects sought in the care oi fallow land are (1) the 

 conservation of soil moisture accumulated during the year for the 

 use of the next crop, (2) the eradication of weeds and volunteer 

 grain wdiich, if allowed to grow and produce seed, would be damaging 

 to the wheat crop, and (3) the securing of a satisfactory seed bed. 



[Cir. 61] 



