RANGE MANAGEMENT ON THE NATIONAL FORESTS. 17 



season would result in injury to the range. On most ranges, how- 

 ever, there is at least a small supply of forage made up of plants of 

 which stock will eat very little except in case of necessity. It is best 

 to graze the range so that stock will not be forced to eat this forage 

 of low palatability. Close grazing of this class of vegetation there- 

 fore is an indication that the range is overgrazed, provided the range 

 is suited to the class of stock on it. {See Class Overgrazing.) Un- 

 der such conditions the condition of the stock will not be satisfactory 

 if grazing has been reasonably well distributed over the grazing 

 unit. On the other hand, stock may be thin at the close of the graz- 

 ing season without the range being overgrazed if a large part of 

 the forage is unsuitecl to them. 



Perhaps the most common mistake is to assume that because the 

 stock are in satisfactory condition at the close of the season there is 

 no overgrazing. This may or may not be true. Not infrequently 

 stock in good condition at the close of the season are from ranges 

 on which there is severe overgrazing. Where this is the case there 

 is faulty distribution of grazing, which may be remedied by water 

 development, proper salting, riding, fencing, or a change in the class 

 of stock. Also, stock may be taken off in good condition from a 

 range which has been injured by too heavy grazing during the grow- 

 ing period of the main forage plants. 



The point of importance in this connection is that the condition 

 of the stock when taken off the range is not in itself a reliable indi- 

 cation that the range is not overgrazed. It is true also that no one 

 of the other indicators of overgrazing should be taken as conclusive 

 evidence that a range is being overgrazed or has been overgrazed in 

 the past. Careful examination and observation will usually reveal 

 more than one of these indications of overgrazing. 



INDICATORS OF OVERGRAZING. 



Overgrazing for an extended period will leave " earmarks," which 

 usually will be recognized. To recognize current overgrazing at the 

 time of examination on a range previously not overgrazed is difficult 

 and yet important in order to make timely adjustment. The follow- 

 ing more obvious earmarks are the most reliable indicators of over- 

 grazing prior to the year of examination : 



The predominance of annual weeds and grasses, such as knotweed, 1 

 tarweed, 2 mustard, 3 annual brome grasses, 4 and fescues, 5 with a dense 



1 Knotweed, Polygonum spp. 5 Annual fescues, Fcstuca megalura, F. 



2 Tarweed, Madia spp. micro stachys, F. oromoides, F. confusa* 



3 Mustard, Sophia incisa. and perhaps others. 



4 Annual brome grasses, Bromus hordea- 

 ceus, B. orizaeformis, B. teciorum, and 

 others. 



111479°— Bull. 790—19 2 



