332 WEST VIRGINIA EXPERIMENT STATION 



FURTHER OBSERVATIONS WITH REFERENCE TO DYING PINE 



AND THE DESTRUCTIVE BARK BEETLES DURING 



THE SUMMER AND FALL OF 1892. 



Directly after the circular letter or special report was sent to 

 the owners of spruce and white pine, on July 12th, 1892, I made 

 arrangements to continue the investigation with a view of ob- 

 taining further information relating to the habits and life his- 

 tory of the destructive bark beetle, as well as to study the natu- 

 ral enemies of this and other bark beetles. Learning by inquiry 

 that there was considerable pine growing in the mountains 

 about seven miles from Morgantown, 1 visited on July 17th, 

 1892, the section mentioned, and found the conditions most fa- 

 vorable for conducting the desired studies. A number of large 

 trees of pitch and yellow pine were found that were dying in 

 the same manner as were those observed in other sections of the 

 State, the bark on the upper portion of the trunk being infested 

 with enormous numbers of the destructive bark beetles, and in 

 many cases the beetles were literally swimming in the turpen- 

 tine that was flowing into their freshly excavated galleries in the 

 living bark. This section which I will hereafter refer to as the 

 Tibbs Run forest, was visited again on July 24th, when a large 

 grove of seedling scrub pines was found on Mayh'eld Hill. 1 Hera 

 numerous trees had died and others were dying from the at- 

 tack of the destructive bark beetle, while many others which 

 appeared perfectly healthy were found to be infested with the 

 same insect, the adults of which were excavating their winding 

 galleries through the inner, living bark, the balls of turpentine 

 pushed out-by the beetles from the entrance holes being the 

 only external indication of their presence. On some living and 



1 To be referred to hereafter as the Mayfleld Hill Grove. 



