192 MISC. PUBLICATION 273, U.S. DEPT. OF AGRICULTURE 



or by windstorms are most frequently selected for attack; and if 

 such timber is not promptly removed from the woods, it may soon 

 be completely ruined for commercial purposes. The salvage of fire- 

 killed trees frequently depends upon the rapidity with which they 

 can be removed from the danger of attack by these borers. Un- 

 peeled logs left in the woods during certain seasons of the year are 

 often seriously damaged. 



There is no way in which these insects can be controlled in the 

 woods, and there seems little likelihood that practical methods will 

 be developed that will prevent attack on dead or dying trees or 

 recently felled logs. As with other insects that attack unseasoned 

 wood, about the only thing that can be done is to remove the logs 

 from the woods as quickly as possible and place them in water or 

 run them through the mill and kiln-drying process. A few of these 

 insects, however, are of importance even after the lumber is placed 

 in storage. 



The ponderous borer (Er gates spicidatiis Lee.) is very destruc- 

 tive to the wood of recently killed or felled coniferous trees, to 

 fallen logs and stumps, and even to power and telephone poles. 

 It has been found to be an important determining factor in the 

 salvage of fire-killed Douglas-fir (96). The heartwood of this tree 

 is very resistant to deterioration until penetrated by the large 

 mines of this wood-boring species. The adults are the largest of 

 our western beetles, measuring from iy 2 to 2% inches in length 

 (fig. 89). The color is uniformly dark brown, with the head and 



> 





\ 



j 



"* \ 



W. 



* 



Figure 89. — The ponderous borer (Ergates spiculatus) : A, Larvae; B, adult 



female. Natural size. 



