UTILIZATION AND MANAGEMENT OF LODGEPOLE PINE. 47 



INSECTS. 



Much can be done to prevent serious insect damage in lodgepole- 

 pine stands merely by keeping the forests in the best silvicultural con- 

 dition. The removal of over-mature and unhealthy trees and the 

 thinning of overstocked stands will leave the more thrifty timber, the 

 kind best able to resist insect attacks. When an outbreak does occur, 

 measures of control should be taken promptly, since an insect infec- 

 tion can be dealt with most effectively and with least cost in its incipi- 

 ency. Whenever possible the bark should be removed from attacked 

 trees. This may be done either after the trees are felled or while 

 they are still standing, provided the infested parts can be reached 

 from the ground. Infested trees can frequently be sold or given 

 away under free use, or used for administrative purposes, although 

 in some cases it may be necessary to treat them without any prospect 

 of their immediate utilization. 



Where an insect attack is widespread, a specially organized cam- 

 paign may be necessary. When the mountain pine beetle (Den- 

 droctonus monticolx) attacked the lodgepole pine in the Bighole 

 Basin in the Deerlodge and Beaverhead National Forests in Mon- 

 tana, in 1912, 2,426 trees were treated in late June and in early July, 

 of which 25 per cent, averaging 13 inches in diameter, were felled 

 and peeled for a distance of about 24 feet from the stump. The cost 

 of this work, including brush disposal, amounted to about SI. 75 per 

 tree. The remainder of the trees, averaging 11 inches in diameter, 

 were peeled as they stood to a height of about 8 feet from the ground, 

 at a cost of 39 cents per tree. Trees as small as 6 inches in diameter 

 were infested, but no trees less than 8 inches in diameter were treated. 

 The costs in this case were excessively high, owing to the very short 

 time in which the work could be done, the lack of suitable tools, and 

 to several changes in plan. In 1913, during the 45 days following 

 May 21, a total of 23,393 trees, averaging 12 inches in diameter and 

 standing on an area of 60,000 acres, were peeled as they stood to an 

 average height of 12 feet, at an average cost of 33 J cents per tree. The 

 aim of this work was not to destroy the insects entirely, but to reduce 

 their numbers to a point where their natural enemies, such as birds 

 and parasites, would be able to keep them under control. It is 

 believed that this has been accomplished. The total cost of the 

 work during the two seasons was $9,540.67. This expenditure has 

 rendered safe for the present an overmature stand which will almost 

 surely bring a stumpage price of over $1,000,000 within the next 20 

 years, provided the timber is kept green. During 1913, in the course 

 of a similar control project in lodgepole and yellow pine on the 

 Ochoco National Forest in Oregon, 12,873 trees were treated at an 

 average cost of 50 cents each, on an area of about 12,000 acres. In 

 this case the trees were felled and peeled, and the bark burned. 



