Bill 

 (leaf 2) 



ranges. On heavily grazed ranges, close cropping may prevent the 

 establishment of aspen reproduction. Some damage may result to 

 reproduction even on moderately grazed areas ; wherever aspen stands 

 are desired for timber, protective measures may be necessary. 

 Sampson 4 has shown that cattle will browse this tree to a height of 

 about 70 inches, and that the injury they cause aspen reproduction 

 is slight, except on overgrazed areas. He notes that sheep are more 

 prone than cattle to eat the woody stems of aspen, but that sprouts 

 45 inches or taller are practically exempt from destruction by sheep. 

 Usually cattle dislike to remain for extended periods in the timber, 

 but tend to congregate in the openings, with the result that aspen 

 ranges thus grazed are ordinarily very unevenly utilized. 



Western aspen is generally rated as fair to fairly good or even 

 good forage for cattle and sheep, but usually, is more palatable to 

 sheep than cattle. However, in the Northwest it is considered more 

 palatable to cattle than to sheep in the summer (July-August) and 

 equally palatable in the fall (September-October). 6 This plant is 

 also browsed extensively by deer and elk. On the Kaibab National 

 Forest in northern Arizona, western aspen is one of the principal 

 summer deer feeds, being ranked among the key species; in fact, 

 its use reflects closely the utilization of the forage on the summer 

 range as a whole. Deer also eagerly devour and flourish on the 

 nutritious, fallen leaves during the autumn. Deer and, to some 

 extent, elk apparently prefer aspen range, possibly because of the 

 protection and concealment afforded by the thick stands of this 

 species as well as because of its forage. 



Not all western aspen stands are desirable range, as frequently 

 on the drier sites the plant is associated with a dense undergrowth 

 of such relatively unpalatable shrubs as bearberry (Arctostaphylos 

 uva-ursi], creeping hollygrape (Odostemon repens), and snowbrush 

 (Ceantottwte vvlutinus), or of unpalatable weeds such as mountain 

 goldenpea (Thermopsis montana} , or the undergrowth may be very 

 sparse. It is usually impractical to graze livestock on such areas, 

 even though the aspen retains its palatability. 



Aspen reproduces vigorously by root shoots, but heavy grazing 

 will keep down practically all reproduction ; on closely grazed range, 

 aspen stands frequently assume a parklike aspect, the lack of re- 

 production, in many instances, indicating an overstocked or im- 

 properly grazed range. On such areas, but little aspen foliage is 

 available to livestock, and this may also be true in some of the more 

 mature stands, where reproduction is lacking. 



Western aspen, with its smooth, usually whitish bark, and long- 

 petioled, broad, toothed, trembling leaves has no counterpart in the 

 West. The small flowers, borne in hanging clusters (catkins) , appear 

 before the leaves, and the small seeds covered with long, silky hairs 



4 Sampson, A. W. EFFECT OF GRAZING UPON ASPEN REPRODUCTION. U. S. Dept. Agr. 

 Bull. 741, 30 pp., illus. 1919. 



B Dayton, W. A. IMPORTANT WESTERN BROWSE PLANTS. U. S. Dept. Agr. Misc. Pub. 

 101, 214 pp., illus. 1931. 



