PLATE XVI. 



Sections of wood cut from Balsam Fir, showing rapid growth, after the old spruces 



die or are felled. 



1. Froui fir hy dead tree in cutting of about l^ v S, 



"2. From fir standing by dead spruce in old cutting of about 1886. 



3. From fir standing by dead tree that showed the work of the spruce beetle. Tree 



evidently died about 1SSS. 



4. From fir in blow down of about 1871, which was followed by another in about 



1SS5-S6. 



5. From fir in blow down of about 18S6. 



6. From spruce standing by large tree broken by a storm about 1886. Evidence 



was found in this tree that it was living when felled and that it had been 

 attacked after failing by the spruce beetle. Both galleries and remains of 

 beetles were found in the bark. 



7. Section of small suppressed spruce about 45 or 50 years old — ail natural size. 



o 



