INSECT ENEMIES OF WESTERN FORESTS 



235 



Figure 107.- 



-Felling bark-beetle infested ponderosa pines is the first step 

 in their treatment. 



infesting trees of small diameter (fig. 109) such as small pon- 

 derosa pine, lodgepole pine, or western white pine, infested with 

 the mountain pine beetle or Black Hills beetle, especially where 

 large groups of trees are infested. By using tractors or teams 

 even the larger trees can be handled for treatment by this method. 



The trees are felled usually in one direction, and then, by using 

 peavies, are hand-rolled into piles, or they are dragged by horses 

 or tractors into openings where they can be bunched into large 

 decks. No peeling is necessary, except occasionally on the outer 

 surfaces of the outer logs. The whole pile is then fired and usually 

 is completely consumed. 



This is a very satisfactory method where it can be used and is 

 not only more economical than the fell-peel-burn method but 



