EFFECT OF GKAZINU ON WESTERN YELLOW PINE. 3 



(7) Areas where sheep congregate. /. ., along driveways and on 

 bed grounds. 



The plots were selected where representative rather than abnormal 

 injury was in evidence. In order to secure maximum results from a 

 limited amount of work, the plots were located where the stand of 

 seedlings was fair to good. They were laid out in quadrangles, vary- 

 ing in size from 10 feet by 30 feet to 30 feet by 90 feet, depending 

 upon the size and density of reproduction. 



All seedlings and saplings of a size subject to grazing were 

 counted. An attempt was made at first to classify the damage ac- 

 cording to such divisions as " leader destroyed," " needles removed," 

 etc., but it was found that this did not give an accurate idea of the 

 amount of damage actually done without a great deal of qualification. 

 For this reason, it was decided to base the classification upon the 

 permanent effect upon the development of the tree which, in the opin- 

 ion of the observer, the damage would cause. Plants on which the 

 leader, side shoots, and needles had been so severely grazed that the 

 growth of the plant would be seriously interfered with for at least 

 a number of years, were classed as "injured." Where the damage 

 was not so severe, but if continued would seriously interfere with the 

 development of the tree, the plants were classed as "severely 

 browsed." Where the damage was severe enough to interfere to a 

 very considerable extent with the development of the tree for a period 

 of from one to three years, but not so severe as to affect its ultimate 

 development even though the usual amount of damage were to con- 

 tinue, the tree was classed as "moderately browsed." Where the 

 damage was so slight that its effect w T ould not be noticeable after the 

 current year, the plant was classed as " lightly browsed." 



The trees were classified according to height by ocular estimate as 

 follows : 



Below 6 inches Seedlings. 



6 inches to 1.5 feet 1-foot class. 



1.6 feet to 2.5 feet 2-foot class. 



2.6 feet to 3.5 feet 3-foot class. 



3.6 feet to 4.5 feet 4-foot class. 



4.6 feet to 5.5 feet 5-foot class. 



5.6 feet to as high as were subject to grazing Above 5-foot class. 



Four examinations were made in 1912 and in 1913 at intervals 

 during the grazing season to show the amount of seasonal damage. 

 The first examination was made during May, to record the amount 

 of damage at the beginning of the grazing period; the second ex- 

 amination was made early in July, to indicate the amount of damage 

 that occurred during the spring dry period ; the third early in Sep- 

 tember, to determine the amount of damage done during the best 

 growing period; and the fourth early in November, at the close of 

 the grazing season, to record the damage done during the fall drying 



