acquired and summarized 

 in technical publications 

 and symposium proceed- 

 ings (e.g., Coster and 

 Searcy 1979, Hastings and 

 Coster 1 981 , Thatcher and 

 others 1980, and USDA 

 1981). 



Researchers have also 

 developed hazard-rating 

 systems that relate forest 

 stand conditions to potential 

 beetle infestation and appro- 

 priate control measures 

 (Belanger and others 1981). 

 Numerous insecticides 

 such as chlorpyrifos have 

 been identified and tested. 

 Possible use of predators, 

 such as the clerid beetles, 

 has been studied, along 

 with pheromones and other 

 chemical attractants and 

 inhibitors. Basic studies 

 have evaluated enzyme-, 

 protein-, and hormone- 

 related factors in pine beetle 

 population growth. Still 

 other experiments have 

 determined the effects of 

 cultural practices such as 

 thinnings to favor more 

 resistant tree species. 

 Systems for modeling pine 

 beetle population have also 



been developed (Stephen 

 and others 1980). Through 

 such investigations, a 

 number of recommenda- 

 tions have been developed 

 that may prevent or reduce 

 outbreaks of the southern 

 pine beetle (Swaine and 

 Remion 1981). 



Research on the black 

 turpentine beetle revealed 

 that infestations in thinned 

 loblolly pine plantations, for 

 example, can be limited by 

 minimizing injury to residual 

 trees, avoiding harvesting 

 on waterlogged soils, and 

 applying lindane to dam- 

 aged or infected trees 

 (Feduccia and Mann 1976). 

 Damage from cone and 

 seed insects in seed or- 

 chards can be limited 

 through use of carbofuran 

 (e.g., DeBarr 1978). The 

 pales weevil, a pest causing 

 high losses on some recent- 

 ly cutover and planted pine 

 lands, can be suppressed 

 by chlorpyrifos and other 

 insecticides (Nord and 

 others 1978). Tests of the a 

 microbial insecticide Ba- 

 cillus thuringiensis, have 

 shown much promise in 



38 



