effoctivo control, this who^o wai od 



of infoste--'. trcoa '.ui'ir.fj ono winter. Tha v;or3: of t'.^ese 

 beetles /pes on at about the sane rate eaoh year BO that 

 it ia safe to aseur;<. that each year we will lose at least 

 2,000 yellow pine trees 12 inches and over in diameter 

 unless <_o:r.e steps are ta!:on to control the infestation. 

 The cost of cleaning out the infestation over tho entire 

 watershed during one winter would probably not amount to 

 the loss caused ty the beetles in two seasons 1 work. If, 

 therefore, the value of the timber lost each succeeding 

 year amounts to from one-half to three-fourths of the ex- 

 pense necessary to clean up the region in one season, the 

 tremendous saving of timber which will be effected b7 the 

 control work can be readily appreciated. For this reason 

 we entertain strong hopes that the Bureau of Entomology 

 will recommend to the District Forester that control work 

 be undertaken over the area of the Hayfork watershed next 

 winter. On account of the large number of trees and the 

 large area involved it will not bo practicable to attempt 

 this control work this spring since it could not be com- 

 pleted before the beetles start to fly, and in that event 

 the work we do accomplish might avail but little. A small 

 percent of the infested trees will necessarily be overlooked 

 in this general clean-up but after the majority of the 

 infested trees are eliminated the small number cf infested 

 trees that will be present the next winter can be located 

 and treated by the regular force. 



It is only recently that the importance of insect 

 control work has been realized, and even now it Is not 

 realized fully. On rrany Forests the annual loss through 

 insects approaches closely the annual loss through fires, 

 yet in the past we have been inclined to assume that this 

 loss was unavoidable and have ta^on it as a matter of course. 

 In tho future, however, it should be our aim to acquaint 

 ourselves with the nature and extent of this inject work and 

 to take all possible steps in preventing its continuance and 

 spread. It is quite important* to learn to dictinfuish by 

 the color of the foliage , the '.'ork of woodpeckers and other 

 signs, the trees which are infeoted. A record should be 

 kept in each Hanger District of the location of infested 

 treee, since this information r>ay be of value in control 

 work which we might be able to exercise ourselves if it is 

 on a cr.all scale. If the infested trees over 12 inches in 

 diameter run 4 or 5 trees to the section, it should be con- 

 sidered of sufficient importance to warrant a special 

 report to this office, together with samples of the insects 

 and their work. 



Our awakening to the importance of this insect 

 damage has been so recent that at the present time we do 

 not know to what extent our entire pine belt iray be in- 

 fested. We believe that our reconnaiaarce crew can secure 

 valuable information for us in this respect for the country 

 they will cover during the coining season. In addition, we 

 hope to be able to induce the Bureau of Entomology to detail 



15. 



