Habitat types reflect differences in environments (Daubenmire 1952, 1961; 

 Daubenmire and Reed;^ Roe 1967; lUingworth and Arlidge 1960). Therefore, it is 

 plausible that beetle behavior and survival will differ in the various habitat types 

 also. Reconnaissance of 42 stands in three of the most extensive types containing 

 lodgepole pine disclosed some differences in the intensity of beetle activity. Each 

 stand visited was classed in one of four categories as follows: 



Intensity 

 class 



1 



2 



Criteria 



No beetle-killed trees present. 



Less than one-third of the 

 susceptible trees killed. 



3 One-third to two-thirds of the 



susceptible trees killed. 



4 " Over two-thirds of the susceptible 



trees killed. 



Trees 6.6 inches d.b.h. and larger were regarded as susceptible to beetle attack 

 three habitat types considered were as follows: 



The 



Habitat type 



Abies lasiocarpa/ 

 vaccinium scoparium 



Abies lasiocarpa/ 



Pachistima myrsinites 



Pseudotsuga menziesii/ 

 Calamagrostis rubescens 



Elevation (feet) 



Mean 

 7,470 



7,183 



6,474 



Range 

 6,550-8,450 



6,700-7,800 



6,000-7,750 



Exposures 

 All exposures 

 Mostly northwest 



All exposures and 

 plateaus 



In addition to beetle infestation, the intensity of dwarfmistletoe infection was 

 also estimated in the same stands. Infected and noninfected dominant and codominant 

 trees were counted and the proportion recorded in one of four categories as follows: 



Intensity 

 class 



1 



Criteria 



All examined trees free of dwarfmistletoe. 



Less than one-third of examined trees 

 infected. 



One-third to two-thirds of the examined 

 trees infected. 



More than two-thirds of the examined 

 trees infected. 



^Daubenmire, R. , and R. M. Reed. Progress report on a study of forest types in the 

 Wind River Mountains, Wyoming. Ditto report on file, Intermountain Forest and Range 

 Experiment Station, Ogden, Utah; limited distribution, 3 pp. 1968. 



5 



