(Ainddian Forcslri/ .Journal. Xorvmhcr, U)18 



1929 



of this kind should appear coincident 

 with the perfection of methods for util- 

 izing birch in the manufacture of pulp. 

 Control Measures. 

 The Bronze Birch Borer passes the 

 winter as a larva or grub in the sap- 

 wood of the infested trees, and it is 

 conceivable that if all or nearly all 

 the infested trees were marked while 

 the leaves were on, removed during 

 winter, and utilized before June in 

 such a way that the contained grubs 

 would be killed, the remaining healthy 

 trees would have a fair chance for 

 life. This method of control is per- 

 fectlv feasible on small areas and 



s,hould certainly be carried out wher- 

 ever small holdings become infested 

 but it is obviously impracticable on a 

 large scale under the present con- 

 ditions of logging birch. There ap- 

 pears to be no other method of check- 

 ing the spread of the disease. The 

 only recommendation we feel justi- 

 fied in making in this connection 

 is that, since the white birch in a 

 badly infested district are apparently 

 threatened w^ith destruction within 

 a few years, the white birch should 

 be removed and utilized as rapidly as 

 is commercially profitable. The Yel- 

 low Birch is not so seriouslv afTected. 



The High Mortality of Balsam Fir 



By Dr. C. D. Howe 



At Meeting of Woodlands Section, Can- 

 adian Pulp and Paper Association 



My studies have been restricted to 

 the mixed forests of the hardwood and 

 softwood type, in which the hard 

 wood may form anywhere from fifty 

 to seventy-five per cent, of the stand. 

 So far as the overhead is concerned, 

 the hardwoods are the dominant 

 trees. 



You know that it was in these 

 mixed forests that you first began to 

 cut spruce, taking only the largest 

 trees. You perhaps went over these 

 areas twice, cutting spruce saw-logs, 

 and taking away the best spruce and 

 taking away the last time you went 

 over it, fifteen or sixteen years ago, 

 or less, as the case may be, all the 

 spruce down to the twelve inch 

 diameter limit. You see the effect of 

 that. Cutting the spruce successive- 

 ly and leaving the balsam, you con- 

 stantly made conditions worse for 

 the spruce and better for the balsam. 

 Up to about ten years ago, you did 

 not look at balsam. Balsam was 

 left there and the opening that you 

 made in the crown-cover encouraged 

 its reproduction. Then later you 

 cut out both the spruce and the bal- 

 sam and that stimulated the growth 

 of hardwoods, and the hardwoods 

 grew up, filled in the spaces formerly 

 occupied by the softwoods, and thus 



you converted a mixed forest into a 

 hardwood forest; first by cutting the 

 spruce you gave the advantage to 

 the balsam, and in the past few years 

 you have been cutting a great deal 

 more thoroughly, and you have open- 

 ed up the crown-cover more, and 

 there again you made conditions 

 very favorable to the balsam repro- 

 duction, more so than to the spruce. 

 You go through the forests of the 

 Riordon limits, and the Laurentide 

 limits, and you will be impressed by 

 the abundance of balsam reproduc- 

 tion. You will go through thicket 

 after thicket of balsam, anf if you see 

 a spruce tree, it wdll be a little bit 

 of a suppressed fellow, under the 

 edge of the balsam thicket, or under 

 the hardwoods. 



Balsam versus Spruce. 



Now% this summer up on the Croche 

 River, I found the reproduction was 

 ninety-seven per cent, balsam, and 

 three per cent, spruce, where the cutting 

 had been chiefly spruce, until a few 

 years ago wdien the balsam was also 

 cut. Lower down in the St. Maurice 

 Valley, on areas cut over twice for 

 spruce and once for both spruce and 

 balsam, was seventy-live or eighty per 

 cent balsam. 



