390 % WEST VIRGINIA EXPERIMENT STATION. 



destructive Scolytid enemies of forest and fruit trees, is a vig- 

 orous and healthy condition of the kinds of trees which it is de- 

 sired to protect. In the cultivated forests of Europe, and in 

 the orchards, parks, and lawns of this country this is possible; 

 but in the American forests, except where a thorough system of 

 forest management is practiced, the difficulty of preventing 

 losses from these ravages is much greater. In the case of cul- 

 tivated forests this end is accomplisned by a system of thin- 

 ning out the inferior, unhealthy and matured trees, in order 

 to give the young and vigorous ones the best opportunity for 

 healthy growth. In the indigeneous forests and farmers' wood 

 lots an attack on healthy trees, by Scolytids which are capable 

 of attacking and killing such trees, but prefer to infest injured 

 or recently felled ones, may often be prevented by providing a 

 supply of such material as will be attractive to them. 1 This 

 may be done by felling or girdling a few inferior trees, or cull- 

 ing out useless or objectionable trees during the winter and 

 early spring, and leave them on the ground until the adults 

 of the Scolytids have entered the bark and deposited their eggs, 

 which as a rule, will be accomplished by the middle or last of 

 May, when by removing the bark from the trunks, and burn- 

 ing the branches and tops, they are all destroyed. 



This method is practiced at present in our forests on an enor- 

 mous scale; in fact, nothing in the cultivated forests of all 

 Europe can compare with it in its magnitude. It is not done 

 however, with the intention of preventing the ravages of Scoly- 

 ticjs or to destroy them, but instead, is part of the system of 

 forest destruction practiced here. I refer to the enormous 

 quantity of tops, logs, stumps, and broken trees and branches 

 which occur in lumbering regions. These are invaded by 

 countless hosts of Scolytids and serve as traps in which they 

 are destroyed by forest fires. 



REMEDIES. 



After a tree is once invaded by Scolytids, there is seldom any 

 hopes of its recovery. The only method which appears to be 



1 Recommended by Eichhoff and other German writers. 



