TTIK WESTERN PINE-DKSTROVIN(i 1?.\HKMK?:TLE. 



19 



Flo. 8. — The western piiie-tlestroyiiiK biirkljeetle {Detulioctonits brevi' 

 comis): Galleries in the inner bark. (Original.) 



".sorrel tops," and tli(> (lead oin'.s. with rcddish-l^rown foliafjo, are 

 called "nMl to|).>," t»r. if w it!i hare branches or l>rokon tojKs, are known 

 as 'Mack t(>i)s" or ■l)t(»kcn lops;"" (2) hy small masses of r«\sin 

 (j)ite]i tubes, iii^s. 

 11 and 12, c) in 

 the crevices of the 

 bark of recently 

 attacked living 

 trees, as well tis 

 in tliose of the 

 dyino: and dead 

 ones; and (3) the 

 presence of the 

 species is deter- 

 mined by remov- 

 ing:: the bark from 

 the dyin^: and dead trees and liiuiin*; the characteristic galleries (fig;. 

 8 and Pis. II, III). 



It must be remem})ered, however, that there are many different 

 kinds of insects, some of them closely resemblinj; the destructive 

 species, alwaj^s found in dying: pine trees. Therefore, for the general 

 observer to be positive in the matter, sj^ecimens of insects and work 

 should be sent to the Bureau of Kntoir.ology for authentic identifi- 

 cation. 



DISTRIBUTION. 



The insect is found in southern Idaho throughout, and its range 

 extends to the northern part of the State. It is recorded from Clali- 

 form'a, Oregon, and eastern and western Washington, and, according 

 to Doctor Hopkins, a vari(>ty occurs in Arizona and N(>w Mexico and 

 attacks tlie western yellow jhuc l/'huis jxtruhrofid) and the sugar ])ine 

 (Pinufi InmhirfiaiKi). 



EXTENT OF DAMAGE AND LOSSES. 



With our ))resent knowledge of the destnictive work of this insect, 

 it is evident that a vast amount of timber has been killed by it during 

 the past ten years within tlie range of its distribiition. It is estimated 

 that each year for the past two or three years, from 2 to 5 per cent of 

 the nuitured standing bull pine timber within the section investigated 

 in the summer of 1 !)().") has died as the result of its ravages. 



POSSIBILITIES OF PREVENTING LOSSES. 



With our additional knowledge of the life history and habits of the 

 beetle, we are able to suggest ])ractical methods of controlling it and 

 of preventing a large j)ercentage of the los.ses heretofore cau.sed }«y its 

 depredations. 



« Sc'c Bill. .56, Bur. Ent., U. S. Dept. Agric. The Bhi( k I iilU lii-elle. 



