4(30 BOARD OF AGRICULTURE. [Pub. Doc. 



filled (a difficult task), if we are to prevent decay. But 

 suppose we succeed in this, and the callus grows well from 

 all sides of the wound, well overlapping the tarred or painted 

 surface of the wood, the callus can never become attached 

 to this dead wound-siu-face, but merely grows over it, leav- 

 inof an infinitesimal seam between it and the wood. In fif- 

 teen or twenty years the continual " seeping " of water into 

 the seam will convey decay to the dead wood at the bottom 

 of the wound. 



Some say that the removal of such branches is simply a 

 matter of skilful surgery ; but can they point to one branch 

 wound ten or more inches in diameter that has healed with- 

 out any trace of rot in the wood? Such wounds should 

 never be made if it can be avoided, for they are almost cer- 

 tain to ruin the trunk, sooner or later. They are permissible 

 only when an accident, like the breaking of a large limb, 

 occurs ; when dead or decaying limbs threaten the welfare 

 of the tree ; or when it becomes necessary to head back an 

 old tree, to increase its vigor or fruitfulness. In all these 

 cases decay may be deferred, but not prevented. 



The removal of large limbs from a tree will lessen its 

 capacity for healing wounds, for it greatly reduces the leaf- 

 bearing members, and thereby the leaf surface, which nuist, 

 as we have seen, be depended upon for elaborating the sap 

 which is to deposit the materials to form the callus. The 

 larger limbs grow mostly from near the base of the tree, 

 where wounds do not heal so well as at the top. 



Another objection to their removal is that it is likely, as 

 we have alread}^ seen, to admit too much sunlight, Avhich 

 may result in " sun-scald," weakening the tree and facili- 

 tating the attacks of injurious insects. 



My observations have led me to believe that no limbs 

 over three to four inches in diameter should be removed 

 from any tree if it can be avoided. A large tree in good 

 health should heal three or four such wounds in six or seven 

 years ; some trees may do better than this, while some will 

 not do as well. 



A considerable number of small limbs or shoots may be 

 removed from a vigorous tree in winter in such a manner as 



