212 TIMBER AND SOME OF ITS DISEASES [chap 



remains of the proximal paits of the dead branches 

 are sticking out from the trunk like unsightly wooden 

 horns. Some of these branches may have been broken 

 off by the fall of neighbouring trees or large limbs ; 

 otheis may have been broken by the weight of snow 



l iG 27 —Portion of a tree from wliicTi a branch has been cut off cbbe to the stem 

 C, the cambium, of the branch B^ its cortex 



accumulating dunng the winter ; others again, may 

 have been broken by hand, or by heavy wmd ; and 

 yet others have died off, in the first place because the 

 overbearing shade of the surroundmg trees cut off the 

 access of light to their leaves, and secondly because 

 the flow of nutritive materials to them ceased, being 

 diverted into more profitable channels by the fliourish- 



