Favora±)le sites are in the cooler, higher vegetational zones , where annual precipitation 

 is usually greater than 14 inches. Most species recommended for the intermediate sagebrush 

 sites are also adapted for the favorable areas; however, above 5,500 feet in western Idaho and 

 6 , 500 feet in eastern Idaho , crested wheatgrass has not been productive. Smooth brome and 

 meadow brome become useful about where crested wheatgrass begins to fail. The best pro- 

 ducers on these favorable sagebrush sites are smooth brome, and intermediate, pubescent, 

 fairway, and tall wheatgrasses . Where silver sagebrush is common, the species and methods 

 recommended are the same as for mountain meadows (see pages 22-23). 



Site Preparation and Seeding 



For successful establishment of seeded species, practically all of the sagebrush and other 

 brush species associated with it must be eradicated. Big sagebrush is easily eradicated. When 

 defoliated or burned, it dies and does not sprout from the base. Sagebrush seed ripens in the 

 fall; therefore, areas should be treated before fall to lessen the likelihood of reestablishment of 

 sagebrush. 



Methods of controlling sagebrush are discussed in U.S. Department of Agriculture 

 Agriculture Handbook 277, "Sagebrush control on range lands," by Pechanec et al. 1964. Only 

 a brief summary of eradication methods is given here. 



The three general methods of sagebrush eradication use chemicals, fire, and mechanical 

 equipment. 



Chemical control is useful for releasing a good stand of seeded or native grasses from 

 suppression by sagebrush. It is not entirely satisfactory, though, because it leaves some 

 standing brush, which hinders planting grass. Inferior plants that are not destroyed by 

 chemicals remain and compete with seeded plants for moisture. 



Burning is an effective, economical method of controlling sagebrush. Carefully handled, 

 fire can be a good tool; but improperly used it can damage soil and vegetation. Burning leaves 

 a clean, firm seedbed that requires no further treatment before drilling the seed. U.S. 

 Department of Agriculture Farmer's Bulletin 1948, "Sagebrush burning- -good and bad" 

 (Pechanec et al. 1954) describes burning techniques and necessary precautions. 



Fire completely kills big sagebrush, but threetip sagebrush often resprouts. Low sage- 

 brush can be killed by burning but it is often too sparse to carry a fire. Rabbitbrush and 

 horsebrush sprout freely from the base and roots; so the number of plants often increases after 

 a fire. Mechanical eradication should be used where any appreciable amount of these species 

 is in the cover. 



Almost every year wildfires occur in the sagebrush zone in southern Idaho. Many of 

 these accidental burns leave seedbeds that provide excellent opportunities for seeding. They 

 should be planted the year the burn occurs. Otherwise, undesirable plants will occupy the site 

 and reduce the likelihood of successful establishment of seeded plants . 



Mechanical eradication by plowing is recommended for- sagebrush sites where burning is 

 not feasible. The most common implements are disk-type plows such as the one-way single- 

 axle disk (wheatland type) plow, the heavy offset disk, and the brushland plow. The brushland 

 plow was designed for use on rough and rocky rangelands and is the only machine that can be 

 used on such lands without undue breakage. Depth of plowing ordinarily should be from 2 to 4 

 inches, which is enough to destroy big sagebrush and most herbaceous species. A plowing 

 depth of 4 to 6 inches is required to kill base- or root -sprouting species such as spineless 

 horsebrush and rabbitbrush. 



18 



