16 THE WESTERN HEMLOCK. 



expense in lumbering- conky trees immediately than to cut only the 

 sound timber near at hand. 



The occurrence of fungous diseases is quite variable, but probably 20 

 or 25 per cent of all Hemlock under 3 feet in diameter is affected. 

 Above that diameter the percentage is larger — possibly 50 per cent. 

 Red Fir suffers much less, except in central and southern Oregon, 

 where from 30 to 40 per cent is diseased. These estimates do not 

 mean that so large a portion of the standing timber is actually lost, for 

 often part of a diseased tree can be used, especially in the case of 

 ground-rot. when long-butting constitutes the only loss. (PI. VIII,- 

 fig. 2.) 



INSECTS. 



Dr. A. D. Hopkins, of the Division of Entomology, U. S. Depart- 

 ment of Agriculture, who has charge of the investigation of forest 

 insects, has kindly furnished the following information relating to the 

 insects of the Western Hemlock, mainly quoted from data published 

 by him: 



Very little is known of the insect enemies of the Western Hemlock, or of methods 

 of preventing losses from their ravages. During my investigation in the Northwest 

 in the spring of 1899, under authorization from the honorable Secretary of Agricul- 

 ture and instructions from Dr. L. 0. Howard, some observations were made which 

 convinced me that the Western Hemlock has some very destructive insect enemies. 



In my preliminary report on the "Insect Enemies of Forests in the Northwest, " 

 Bulletin 21, N. S., TJ. S. Department of Agriculture, the following references are 

 made to some of the insects observed: 



On page 8, to an undescribed bark-beetle {Hylesinus sp. ), which was found at New- 

 poit, Oreg., to be quite common in recently felled Hemlock. 



On page 9, to a trouble which had caused the death of a large number of Noble Fir 

 and Hemlock in the Cascade Forest Reserve near Berry, Oreg. While I was not able 

 to secure specimens of the insects which doubtless caused the death of these trees 

 owing to the fact that the trees had been dead too long, I concluded from the char- 

 acter of their work on the outer sapwood that it must be a Buprestid, possibly 

 belonging to the genus Melanophila. Many of the wounds made by the insect had 

 healed over before the trees died, thus presenting conclusive evidence that they 

 were attacked while living and probably while in a healthy condition. 



In the vicinity of St. Helen, Oreg., investigations were made of a serious trouble 

 affecting the Hemlock and Red Fir, which proved to be similar to, if not identical with, 

 that affecting the Hemlock and Noble Fir in the Cascade Reserve. The work of appar- 

 ently the same Buprestid larva? was found in healthy, dead, and dying trees, and I 

 was fortunate in securing a few larva; ; also some nice specimens of healed-over gal- 

 leries. The latter presented conclusive evidence that the attack had been made on 

 healthy growing trees. It seems that the trees succumb only after several years of 

 successive attack by this insect. The extensive cutting of timber for fuel carried on 

 here does not seem to answer the usual purpose of attracting the insects away from 

 the living trees; therefore this is a problem of considerable interest, and, under more 

 favorable conditions for study, should receive attention in order to determine some 

 methods of preventing the ravages, which may prove to lie even more extensive than 

 at present. 



