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The Eastern Spruce Bark-beetle is the most serious enemy of Spruce in the East, 

 and pines, spruces, balsam and larch are all attacked by destructive species. There 

 -.ire more extensive injuries by these beetles in British Columbia forests. The 

 , pines, spruces, balsam, hcmflock, larch and Douglas fir are all attacked by de- 

 ^structive species. The buH pine and western white pine have suffered very se- 

 cverely. The trees which are killed by the destructive beetles are attacked by bor- 

 ' ing beetles of many species and the timber more or less quicqly ruined. 



In addition to the true Bark-beetles the Ipidae include the Ambrosia beetles, 

 or Timber-beetles, which excavate smal'l black tunnels into the wood for from less 

 than an inch to nearly a foot. These are common in freshly cut stumps and logs, 

 in weakened trees and fire injured or recently killed timber. They invariably select 

 green wood in which there is abundant sap; but usually prefer trees in a badly 

 weakened or dying condition. Their sma'll black tunnels often seriously reduce 

 the value of logs left out of water during the summer. 



The defoliating insects have been much in evidence during the past few years. 

 In Quebec, Ontario, and in British Columbia there have been extensive outbreaks 

 of Tent-caterpillars. Large sections of hard woods have been completely stripped. 

 The work of these caterpillars is over by the first of July, and the trees have consi- 

 derable opportunity for recuperation during the remainder of the season. It is 

 difficult to estimate the actual injury caused by these outbreaks of tent-caterpillars. 

 The trees usually recover in considerable measure, but the effect of the injury is 

 apparent in the dying branches and unthrifty condition of many of the trees 

 after such attacks. The tent-caterpillar outbreak in Quebec Province was very 

 severe in the season of 1913 ; but controlling factors were becoming evident in some 

 sections. In the Gatineau Valley immense numbers of the caterpillars died from a 

 wilt-disease just before reaching maturity. As a result doubtless of this high mor- 

 tality the egg-masses are much less numerous in that district this spring than in 

 the previous two seasons. About Ottawa, however, the egg masses are still very 

 abundant, the moths were attracted by the city lights and have reinfested a sec- 

 tion from which the egg-masses were almost entirely removed by hand in the 

 winter of 1912-13. 



The Larch Sawfly has spread as far westward as Saskatchewan, and Mani- 

 toba larch woods are reported as badly infested, with many trees dying. A se- 

 rious outbreak appears to be commencing in New Brunswick woods, and has been 

 preceded by an attack of the Larch Case-bearer. The adult sawflies lay their eggs 

 in slits cut along one side of the twigs in spring. The infested leaves become 

 curled and are thus readily distinguished. The caterpillar-like larvae, or young, 

 feed upon the needles and more or less completely strip the trees. Successive de- 

 foliations result in the death of the trees. The Case bearer is a very minute cater- 

 pillar which feeds on the substance of the leaves through a hole cut in the side. 

 Each caterpillar carries with it a minute case formed of a portion of a leaf which 

 it has hollowed out and a superstructure of silk. The injured leaves die, and more 

 or less defoliation results. 



The Spruce Budworm is another well known defoliator. It occurs through- 

 out Canada on vSpruces, Hemlock, Balsam, Douglas, Fir and Larch. In the East 

 it is most noticed in Spruce Forests. The catcrpiWars feed upon the buds and 

 needles of the outer twigs, so that the dead and brown foliage of the outer twigs 

 gives the trees a fire-injured appearance. Usually the trees recover, although at- 

 tacked two or three years in succession. After three years the parasitic enemies 



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