24 A PROTECTED STOCK RANGE IN ARIZONA. 



SUMMARY. 



The lands under consideration in this paper appear to regain their 

 original productivity in approximately three years of complete pro- 

 tection. 



Evidence thus far secured seems to indicate that the best lands in 

 the vicinity will improve under stocking at the rate of one bovine 

 animal to 20 acres. The poorer lands take a correspondingly larger 

 acreage for each animal. The areas that will carry now one head to 

 20 acres are very limited. 



Brush and timber are encroaching upon the grass lands, due, it is 

 believed, to protection from fires. 



A ground cover is not a factor below an altitude of about 3,500 feet. 



Although the maximum yield of forage may be reached in about 

 three years of protection, improvements in quality of forage will 

 probably go on longer through the continued supplanting of annual 

 plants by perennials of greater value. 



Thus far alfilerilla is the only introduced plant which has succeeded, 

 and this only in the most favored situations. It does not appear 

 to thrive in competition with the native perennial grasses at these 

 altitudes when the latter are not grazed. 



None of the other two hundred lots of seed sown have given any 

 promise of success except those of three or four native species. These 

 give beneficial results, but the cost is high. 



Results seem to be secured much more rapidly by proper protection 

 from overgrazing than by any other method. 



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