KANGE MANAGEMENT ON THE NATIONAL FORESTS. 69 



quent change of bedding ground. The bedding-out system of herding 

 so widely adopted in handling sheep should be approached, if not 

 adopted, in the handling of goats on the range. Unless these precau- 

 tions are observed unwarranted injury to both range and tree growth 

 may be expected. 



ASPEN. 



A study to determine the effects of grazing upon reproduction of 

 aspen was conducted over a period of years on the Manti National 

 Forest. 1 It was found that the leafage of young twigs of aspen is 

 browsed in varying degree by both sheep and cattle. Sheep may be 

 responsible for severe damage to aspen reproduction both in stand- 

 ing timber and on clear cuttings, regardless of the variety and sup- 

 ply of other choice forage. The damage from cattle grazing is 

 usually slight, except where the range is overgrazed and around 

 water, salt licks, and shading and bedding grounds where the cattle 

 congregate. 



Observations over a period of five years on range in standing tim- 

 ber showed that 27.2 per cent of the aspen reproduction under about 

 40 inches in height was killed by light sheep grazing; 31.8 per cent 

 by moderate grazing; and 65 per cent by heavy grazing. On clear- 

 cut plots the damage annually was found to be exceedingly heavy. 

 Three years of successive sheep grazing on such plots following clear 

 cutting of the standing timber resulted in complete destruction of the 

 aspen reproduction. After the sprouts reach a height of about 45 

 inches, which takes about three years, they are beyond destructive 

 browsing by sheep. 



The foregoing conclusions apply, no doubt, to other central Utah 

 Forests than the Manti. Observations elsewhere do not always show 

 such marked damage from sheep grazing on range where other forage 

 suitable for sheep is available. It is a fact, however, that overgraz- 

 ing or heavy grazing by sheep will prevent a good stand of aspen 

 reproduction. Continued overgrazing by cattle also will seriously in- 

 terfere with, if it does not prevent, satisfactory reproduction. 



It is imperative, therefore, to avoid overgrazing and mismanage- 

 ment of the stock. In addition, only well-regulated, moderate cattle 

 grazing should be allowed in clear-cut and thinned aspen forests 

 during the first three years after cutting or thinning, if it is desired 

 to secure a satisfactory stand of aspen reproduction. 



IMPOETANCE OF PROPEE MANAGEMENT OF THE EANGE AND THE STOCK. 



In this whole problem of adjusting grazing so that it will not 

 interfere to an unwarranted extent with timber production the 

 foundation is grazing management and management of the stock. 



1 Sampson, Arthur W. Effect of Grazing upon Aspen Reproduction. U. S. Dept. of 

 Agriculture, Bui. 741, 1919. 



