Though less desirable than a silvicultural approach, chemical control could offer 

 some temporary relief. In recent work (Bukzeeva 1965), 100 percent control of M. 

 frontalis adults was achieved by dusting trees with 12 percent BHC (Benzene Hexa- 

 chloride) at 18 pounds per acre at a period when adults were feeding. This approach 

 could conceivably be taken with M. gentilis on lodgepole pine because the feeding habits 

 of M. frontalis and M. gentilis adults are similar. 



The association of the weevil and the lodgepole pine thinnings is an excellent 

 example of how silvicultural operations altered the forest environment to provide con- 

 ditions suitable for the development of a hitherto unknown pest of forest regeneration. 

 Another instance of Magdalis damage associated with forest management practices has 

 been observed since 1968. In 1969, Magdalis (probably leoontei Horn) adults caused 

 spectacular defoliation to a young stand of ponderosa pine on the Fremont National 

 Forest several miles south of Silver Lake, Oregon (Dolph and Pettinger 1969). Accord- 

 ing to reports,^ weevils were observed on July 26, 1969, feeding on needles around new 

 bud clusters on small trees left standing in a 40-acre area from which the overstory 

 had been logged. 



^Personal communication on March 13, 1970, with Mr. Benton Howard, former Branch 

 Chief, Insect and Disease Control, Division of Timber Management, USDA Forest Service, 

 Region 6, Portland, Oregon. 



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