BULLETIN 741, U. S-. DEPARTMENT OP AGRICULTURE. 



grazed plots, of 14.6 per cent on moderately grazed areas, and of 4.4 

 per cent on heavily grazed plots. The small percentage on the 

 heavily grazed plots is due to the high mortality of specimens on 

 these plots in previous seasons, which left for observation relatively 

 few specimens having terminal shoots. Table 5 shows that for the 

 whole period from 1912 to 1916, inclusive, the greatest number of 



grazed sprouts, especially those up 

 to a foot or so in height, were in 

 general found on heavily cropped 

 plots, and that the least injuries 

 occurred on the lightly grazed plots. 

 When the total number of sprouts 

 occurring on the plots and the 

 number injured are considered col- 

 lectively for the five years, regard- 

 less of grazing intensity, a little less 

 than half (40 per cent) is found to 

 be injured by browsing. This is 

 considerably lower than on the 

 heavily grazed plots. On most 

 plots the stature of the specimens 

 was appreciably more reduced on 

 the heavily grazed lands than on 

 those where grazing was light or 

 moderate, the portion of the speci- 

 mens remaining often being mere 

 snags, as is shown in figure 2 of 

 Plate I and figures 1 and 2 of 

 Plate II. In the most extreme 

 cases all the leaves, much of the 

 tender woody growth, some of the 

 buds, and portions of the bark were 

 eaten. 



The proportion of specimens with 

 both leaders and laterals browsed 

 is least serious on the lightly grazed 

 plots. On moderately grazed areas 

 the percentage is considerably more, 

 and on heavily grazed areas it is the highest of all. This holds true 

 both for 1915 and 1916. For the five-year period 1912-1916, Table 4 

 shows that, regardless of height classes, the average percentage of 

 injured sprouts is least on the lightly grazed plots, intermediate on the 

 moderately grazed areas, and largest on the heavily grazed plots, the 

 figures being 14.1, 24.9, and 53.1, respectively. The results are similar 





20% 

 10'U 

 0% 



10% 

 0% 



60% 

 40% 

 20% 



60% 

 40% 

 20% 







1916 

 /9/S 



1315 

 1916 



1916 

 19/5 



/9/S 

 /9/S 





— ~^r^ 









,-''' 



»«• 



'-'' "^-^ 











v 



— 











/ 





/ _ v 









LightlyGrzzed Moderately Grszed Heavily Grazed 



=rrr Leader Si Laterals Browsed 

 1""~~ Leader Browsed 

 tm Una razed 



Toial Mortofity 



Fig. 1. — Relation of injury of sprouts to intensity 

 of grazing seasons 1915 and 1916. 



