THE BLACK HILLS BEETLE. 19 



METHODS OF CONTROL. 



The results of our investigations to date suggest but slight changes 

 in our recommendations in 1901 and 1902, published in Bulletin 32 

 (pp. 21, 22), as follows: 



It appears that the pine-destroying beetle of the Black Hills, like its eastern relatives, 

 depends on the trees killed by it for the augmentation of its numbers and the perpetuation 

 of its power of killing more trees. Therefore it is only necessary that the attacking force be 

 reduced to a point where it can no longer overcome the vital resistance of the trees on which 

 it concentrates its attack in order to successfully defeat it. 



The fact that the attacking force of the enemy is already weakened from natural agencies 

 suggests that they can be reduced by artificial means below their power of killing more trees 

 next season, and thus bring the trouble to an end. Therefore the following are suggested 

 and recommended as probably the best methods of accomplishing this result: 



(1) Determine the location and extent of areas in which trees were attacked during the 

 summer and fall (of 1901) and the number of trees now infested with living broods of the 

 pine-dest roving beetle. 



(2) Select those areas in which there are the largest number of infested trees and mark 

 the same for cutting. 



(3) Secure, by sale contracts or otherwise, the cutting of these trees and the removal of 

 the bark from the infested parts of the main trunks and stumps prior to May 1 ( 1902). The 

 drying of the removed infested bark and surface of the wood will effectually destroy the 

 insects. In addition the logs so treated will be protected next spring and summer from the 

 attack of wood-boring insects, and thus be almost or quite as valuable for all commercial 

 purposes as if cut from living trees. 



It is not necessary that all infested trees in the reserve or those of all other infested areas 

 should be thus cut and barked, but it is important that a large percentage should be so 

 treated in order to insure a sufficient reduction of the beetles to check their destructive 

 ravages. 



Experience has shown quite conclusively that the above recom- 

 mendations are entirely practicable, and it has also been demon- 

 strated that whenever the felled trees are accessible for lumber, ties, 

 mining timbers, or cord wood it can usually be sold for more than the 

 cost of cutting and barking. 



APPLICATION OF THE METHOD IN THE BLACK HILLS. 



There has been a continued effort to control this destructive beetle 

 in the Black Hills Reserve since 1901. but the adoption of the neces- 

 sary radical measures was prevented by certain regulations governing 

 the management of the reserve, which required the advertising and 

 sale of the old dead and dying timber, for which there was not a suffi- 

 cient demand in the State of South Dakota: and since a special pro- 

 vision of the law prohibited the shipment of timber out of the State. 

 it was practically impossible to accomplish anything of importance. 



We are informed, however, that the evident benefit in certain sec- 

 tions resulting from cutting and barking the infested timber is such 

 as to indicate that if more radical measures had been adopted under a 

 more liberal policy of timber salt's, and under a temporary amend- 



