The Problem of the Bark Beetle - «9 



Problem of the Bark Beetle 



Bij J. M. Suaint, in chanjt of Forest Insects, Entomological Branch, De- 



partmrnt of Agriculture, Ottawa. 



Editor'n Xote. — Readers of the Canadian Forestry Journal will find the following article 

 of compellint: interest from beginning to end. The bark beetle in the Western forests is an 

 enemy second only to fire in power of destruction and demands immediate and determined at- 

 tention at the hands of Governments and others responsible for forest preservation. 



The injury caused by insects is evident enough nearly everywhere throughout our forests. 

 In the eastern provinces the spruce, taniarac, balsam, poplar and birch have suffered severely 

 from this cause; but the most e.xtensive and destructive forest insect outbreaks of recent 

 years have occurred in the southern and western parts of the Province of British Columbia. 

 In the triangle lying between the Gold Range and the Cascades the yellow pine and the 

 western white pine have been suffering for about eight years from an attack by two species 

 of very destructive bark-beetles, the Western I'ine Bark-beetle and the Western White Pine 

 Bark-beetle. Both species of beetles are found attacking and killing the yellow pine in the 

 same locality and even in the same tree, although the Western White Pine Bark-beetle seems 

 to be usually more abundant. The infested area extends from the mountains east of Okana- 

 gan Lake westward to Princeton and Nicola, and is still sjjreading to the west and north. 

 The same trouble in the yellow pine has been reported from the Kootenays, but no exten- 

 sive infestation is known as yet east of the Gold Range. 



The losses in portions of this country have been enormous. Tn the section infested the 

 longest, apjiarently about eight years, practically all the pines have been killed and the 

 whole countryside appears as though swept by great fires. In the more recently infested 

 localities the injured timber appears as clumps and streaks of "red tops" with numerous 

 isolated <lying or dead trees. Unless the condition of the timber trade will warrant ex- 

 tensive control measures in the near future, the outlook for the yellow piile in British 

 Columbia is very serious indeed. 



WHITE FIXE WOBST SUFFEFEF. 



The western white pine in the same section of country has suffered even more seriously 

 than the yellow pine, Vjut its loss is not so important because of much less extent. The 

 oldest outbreak in the white pine so far discovered is at Sugar Lake, east of Vernon. 

 There the destruction has been in j)rogress for about ei^t years and a large body of fine 

 timber has been killed. The outbreak was still spreading rapidly when last visited. The 

 Western White Pine Bark-beetle is the species responsible for the death of the trees. It 

 app>ears to be working everywhere throughout the province where the white pine occurs, 

 and if the present comlitions continue, it will ajiparently kill out the white pine entirely in 

 many sections. The owners of any valualtle stands of this timber should be on guard 

 against this most destructive enemy. Its injury is marked by dying trees, isolated or in 

 dumps, with the bark studiled with gum-tubes, with the foliage fading to yellow during 

 fall and winter and becoming red by the following July. 



The black pine of lodge pole pine, Pinus murraijana, is also readily attacked and 

 killed by the Western White Pine beetle; considerable destruction in this timber has been 

 locateil. 



The Douglas fir and western larch are subject to attack by the Douglas fir Ijark-beetle, 

 but serious outbreaks are not known to occur at present. This beetle usually finds sufficient 

 accommodation in slash and weakene<l or badly injured trees. 



The Englemann spruce and the Sitka spruce are each attacked by a destructive species 

 of liark-beetle. and in several places considerable loss has occurred. The western hemlock 

 and the western balsam also suffer from attacks by several species of destructive bark- 

 beetles. The bark-beetle outbreaks in the forests of British Columbia are fast becoming a 

 very serious problem. 



OUTBBEAKS CAN BE CONTFOLLED. ■- 



Fortunately, outbreaks of injurious bark-beetles can be controlled, if not neglected too 

 long, and usually without great expense. The habits of the beetles are such that it is 



