Table 2 . -- Intensity of tree killing by the mountain pine beetle 

 (Beaverhead National Forest 1923-1940) 1 



Trees per acre before 



infestation^ 



Lodgepole pine : Other 



Location 



Elevation 



Vegetational 

 zone 



Trees per acre killed by 

 the mountain pine beetle 



Battlefield 



Wise River 



Elkhom 



Feet 



6,400- 

 7,300 



6,400- 

 7,300 



7,200- 

 7,950 



-Number 



Douglas -fir v. 1,203 ,., 21 



Douglas-fir 



533 



Subalpine fir- 1,044 

 Engelmann spruce 



180 



12 



Number 



209 



46 



24 



Percent 



17.4 



8.6 



2.3 



^Compiled from data collected by Archie Gibson, 

 ^Includes trees 3 inches d.b.h. and larger. 



Table 3. -- Intensity of tree killing by the mountain pine beetle 

 (Bitterroot National Forest 1923-1940) ^ 



Plot 



Elevation 



Vegetational 

 zone 



Trees per acre in spring 1923^ 

 Lodgepole _ Douglas- _ Ponderosa 

 pine ■ fir ' pine 



Trees per acre killed b 

 the mountain pine beetl 



Feet 

 5,400 

 5,400 



5,100 



6,000 

 7,100 



4,750 



Douglas-fir 

 Douglas-fir 



Douglas-fir 



Douglas-fir 



Subalpine fir- 

 Engelmann spruce 



Douglas-fir 



320 

 32 



260 

 172 

 172 



256 



Number 



32 



136 



72 



40 



Number 



272 



LPP 32 

 PP 116 



216 



140 



112 



112 



Percent 



85.0 



100.0 

 85.3 



83.1 



81.9 



65.1 



I 



43.8 



^Compiled from data collected by Archie Gibson. 

 ^Includes trees 3 inches d.b.h. and larger. 



4 



