INSECT ENEMIES OF WESTERN FORESTS 



105 



Figure 52. — Long vertical eu^ .galleries are characteristic of mountain pine beetle work. 



A clerid beetle {Enoclerus)^ a fly {Medetera)^ and a parasitic 

 wasp {Coeloides) are the most active insect enemies. Woodpeckers 

 also prey upon the species, and climatic conditions often are impor- 

 tant as natural control agencies. 



