Kov. i6. 1914 Revegetation of Range Lands 121 



failure of the forage plants to produce seed, reproduction is prevented, 

 resulting in a gradual decline in the carrying capacity of the lands. 

 Even under conservative use the carrying capacity of the range does not 

 improve rapidly through reproduction of the more desirable species. 



YEARLONG PROTECTION 



To determine the practicabiUty of reseeding the range through year- 

 long protection from grazing, five typical overgrazed areas, situated at 

 various elevations from 3,000 to 7,500 feet, were selected for study. 

 Each area was fenced in 1907, and observations were made during four 

 successive seasons. The results from the areas in each zone are pre- 

 sented separately. 



HuDSONiAN Zone. — The areas closed to stock in the Hudsonian zone 

 had been subjected to close yearlong grazing for several seasons (PI. 

 XXI, figs. 2 and 3), and because of the resultant low vitality of the 

 vegetation practically no seed was produced during the first two seasons. 

 In the third and subsequent seasons, however, a satisfactory seed crop 

 of average viability was produced. The vegetative changes which took 

 place in representative quadrats are shown in text figures 5 and 6. 



It will be seen that at the time of their establishment the quadrats 

 contained no perennial forage seedlings. The first year passed without 

 any making their appearance. In 1909, however, 7 seedlings appeared 

 after the germination period, but, as shown in figure 6, only 5 survived 

 the subsequent dry season. On the denuded quadrat (fig. 6, quadrat 2) 

 2 mountain-bunch-grass seedlings came in during 1908, both of which 

 succumbed later. In 1909, 10 seedUngs were found in the spring, only 

 6 of which survived the season. Seed was produced in abundance each 

 year, but for the most part remained on the surface of the soil. At the 

 beginning of the study the quadrats were stocked with an inconspicuous 

 and useless plant called knotweed [Polygonum ramosissimuni) , which is 

 common on overgrazed ranges throughout the mountain-bunch-grass 

 association. On the permanent quadrats this species no more than held 

 its own, but on the denuded plots it increased prodigiously. 



The contrast in the aggressiveness of reproduction of the annual and 

 perennial species on protected areas, as shown in the case of mountain 

 bunch-grass and knotweed, holds generally. The only perennial species 

 which reproduced well under yearlong protection was western porcupine 

 grass, the seed of which, as already pointed out, is planted by means of 

 an awn attached to the floral glume. 



The fact that practically no reproduction from seed was secured as a 

 result of yearlong protection does not necessarily mean that such pro- 

 tection will not bring about an increase in the carrying capacity of the 

 range. As a matter of fact the carrying capacity was increased through 

 the production by the original perennial plants of more and longer leaf 



