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JOURNAIy OF FORESTRY 



tion in the Northeastern States than in Minnesota. The reason for this 

 difference cannot be explained with any degree of certainty at the pres- 

 ent time, although there are several factors that may have an influence, 

 such as the occurrence of natural enemies of the weevil in Minnesota, 

 which are not found in the East, the extent of spring and fall fires, and 

 differences in the silvical habits of the white pine in West and East. 



In so far as has been found up to the present time, there are no para- 

 sites of the weevil found in Minnesota that do not occur throughout its 



Fig. 3. — General distribution of the white-pine weevil in the range of its host tree 



whole range. Certainly there are none abundant enough to cause such 

 a difference between the two sections. Neither is there any greater 

 abundance of birds which might help to control the weevil. It is proba- 

 ble, however, that there have been more extensive spring fires in Minne- 

 sota and Wisconsin than in the Eastern States and this may have had 

 some influence. A light fire burning through the litter in the spring, 

 before the emergence of the adult weevils from hibernation, would 

 undoubtedly kill immense numbers of them. If such a fire were exten- 

 sive, it would reduce the number of weevils materially in the area 

 burned. The most common parasites of the weevil pass the winter in 



