SHADK TREK AND TIMBER DESTROYING FUNGI. 231 



over. During this long time the fungus mycelium had an oppor- 

 tunity to enter, travel down the heart wood of the trunk and 

 reach the butt. It is interesting to observe that while the fun- 

 gus mycelium gained entrance through the broken area of the 

 leader in the top of the tree, and traveled downward, the greater 

 injury to the trunk was some distance below. This is probably 

 due to the greater amount of free resin in the younger portion 

 of the trunk above. While the mycelium traveled downward 

 through this, it did not spread rapidly here nor bring about 

 such a complete 

 disintegra t i o n of 

 the tissue. Sec- 

 tions of the trunk 

 just below the 

 point where the 

 fungus entered, 

 and for some dis- 

 tance below, show 

 the heart wood is 

 finer and harder 

 though invaded by 

 the mycelium. The 

 wood is also very 

 m uch stained, 

 brown irregular 

 areas often marked 

 off by black lines, 

 or divided up into smaller areas by black lines. The mycelium 

 also traveled upward in the newly established leader of the tree. 

 From the trunk it had invaded many of the branches in the 

 same way. As is usual in such cases a number of the branches 

 had been killed. These dead branches then yielded readily to 

 the disintegrating action of the fungus. 



On a few of the limbs fruit bodies of Tramctes abietis were 

 found. A branch bearing a fruit body and broken at this point 

 shows the gross structural characters of the wood affected by the 

 mycelium of this species. This is shown in the photograph. 

 At one stage in the decay of the wood there are numerous areas 



90. Rotten section front rotted log of red spruce. 



