be done to the soil and grazing capacity of the area. Pickford 3 

 reports that on dry, overgrazed, spring-iall Utah ranges, although 

 the big sagebrush cover may be reduced 80 percent or more by burn- 

 ing, the grazing capacity has been lessened over 50 percent. This is 

 due largely to the replacement of highly palatable perennial bunch- 

 grasses by inferior species, particularly downy chess (Bromus tec- 

 torwrri), and a notable invasion of such worthless "fireweeds" as 

 certain species of rabbitbrush (Ghrysothamnus). Undoubtedly the 

 decrease of palatable perennial grasses, after being exposed through 

 the elimination of the sagebrush, was the result of the overgrazing 

 on these ranges. Even on areas promiscuously burned, however, and 

 long protected from grazing, burning tends to deplete the stand of 

 perennial grasses and to allow annual grasses, chiefly downy chess, 

 to increase sharply in density as compared to uriburned ranges 

 protected from grazing. 



In areas where moisture is relatively good and where there is a 

 remnant of palatable perennial grasses in the sagebrush stand, burn- 

 ing under properly controlled conditions may be effective in eliminat- 

 ing the dense sagebrush and improving the grazing value of the 

 type. Hanson 5 and Morris, 6 at about 8,000 feet elevation in the 

 Laramie Eiver Valley in northern Colorado, on an area with an 

 annual precipitation of about 20 inches, a dense stand of big sage- 

 brush, and a large variety of deep-rooted perennial grasses, obtained 

 an increase in the grazing capacity of experimental plots by burning. 

 The burning was done in early October and with a favorable wind. 

 The area was closed to grazing and on some plots rodents were elim- 

 inated. Under such conditions grasses showed an increase in each 

 of the 3 years following burning, although only about half or 

 two-thirds as great as on the area unburned but grubbed of sagebrush. 



Recent studies of the burning of sagebrush in southeastern Idaho 

 by the Intermountain Forest and Range Experiment Station indi- 

 cate that there was slightly less loss in perennial grasses between the 

 good year 1932 and the very severe drought year of 1934 on areas 

 burned to varying degree and protected from grazing than on un- 

 burned and ungrazed sagebrush areas. On burns of heavy intensity, 

 however, a very significant decrease in organic matter in the top soil 

 is apparent, as well as a decrease of nitrogen and moisture equivalent. 



Big sagebrush produces so much pollen that when the wind blows 

 small yellow clouds of this material are easily discernible in locali- 

 ties where this species occurs. This pollen is the source of many 

 cases of hay fever. Numerous seeds of high viability are produced 

 during September. 



This species, although never used officially as a drug, has been 

 much employed locally as a tea substitute, general tonic, a hair and 

 eye wash, in treating colds and diarrhea, and as an antiseptic for 

 wounds. Since the wood ignites easily, burns rapidly, and produces 

 an intense heat, it provided an invaluable fuel for the Indians and 

 early explorers, a use perpetuated by tourists and other visitors 

 to the treeless areas where this plant grows. 



8 See footnote on preceding page. 



6 Hanson, H. C. IMPROVEMENT OF SAGEBRUSH RANGE IN COLORADO. Colo. Agr. Expt. 

 Sta. Bull. 356, 12 pp., illus. 1929. 



6 Morris, M. S. INCREASING FORAGE ON SAGEBRUSH LAND. Colo. Agr. Expt. Sta. Bull. 

 308-A, 7 pp., illus. 1931. 



