an ezpert for on examination of the remainder of tho pine 

 bej.t of thia Forest during the coming summer, oo that if 

 any other extenjive areas of infestation are found hd nay 

 be able to ra'-e a working plan for tho Forest by v:aterBhed 

 units, by .:hich we cay in the course of severe.1 years of 

 control work put a otop to this large annual IOES of timber. 



\7henever occaeioR presents itself, we should 

 endeavor to correct the false inprocsion that prevails in 

 the niruls of many and is often expressed by ther.j namely, 

 that tho prevelanoe of timber destroying inoecta is due to 

 the suppression of Forest fires. Injury by firo nncouragea 

 the entrance of destructive* insocto into the injured trees. 

 A ground fire would have no possible destructive effect 

 upon the bark beetle and flat-headed borers v^ileso it rrere 

 sufficiently hot to scorch the cambium and kil] the troeo, 

 also. The only fire hot enough to 1:111 these insects is a 

 cro:?n fire, which would destroy the forest as well* The 

 insects which would suffer destruction from curfaco .fireo 

 would be those living in dorm and decaying timber, v;hic!i 

 are not the ones usually that attack and hill the livo troeo. 

 Surface fires could have no possible benoficial effact upon 

 the control of the insects which are the chief agents of 

 destruction of our yellow pine, since these inrocts from the 

 egg state to the adult beetle live under or within the bark 

 of tho trees. The western pine beetle infests all portions 

 of the trunk of the tree, or if it neglects any portion it 

 is more likely to be that near the base of the tree, oince 

 ~ar.y trees are infested by thio species only in the upper 

 portion cf the trunk: the absurdity of fires for Its control 

 will, therefore, be evident. 



Every kind of tree, like every kind of animal, is 

 subject to the attacks of destructive agencies. There is 

 nothing reculiar In the fact that the yellovr pine has 

 insect enemies as well as our fruit trees. Thorp is no more 

 reason for sending a fire through a forest to kill bark 

 beetles than there would be to run a fire through an orchard 

 to kill insects which might be within the twigs or under the 

 bark of some of the trees. Such treatment would do a great 

 deal of damage to the entire stand and would do no harm to 

 the insects we are after. Any treatment to be effective 

 must be given to the individual trees. 



Some insect infestations run through cycles, the 

 insects increasing in numbers very rapidly through a period 

 of years and doing a vast amount of destruction, and then 

 for some reason disappearing almost as ruiclrly as thoy 

 appeared. Others, like Dendroctonus brevicomis and 

 flat-headed borer, work along at about the sane rate or 



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