WOUNDS 251 



by the occluding callus, and which of course greatly reduces the 

 value of the tree for technical purposes (Fig. 145). 



Thus it is always a good plan, in the case of every variety of 

 tree, to remove as early as possible all the larger dead branches 

 that have succumbed to the natural shading processes. I do not 



FIG. 143. An oak-branch which 

 has succumbed to the natural 

 process of shading, its base, b, 

 however, stiil receiving nourish- 

 ment from the main stem. 



FIG. 144. The snag of an oak-branch which 

 has dropped off after being killed by the 

 natural process of shading. The basal por- 

 tion, b, of the branch which remained alive, 

 and originally projected from the stem, has 

 been grown over. After a callus has formed, 

 the dark brown zone, c, between the living, 

 b, and the much- decomposed wood, a, re- 

 mains unchanged in the interior of the tree, 

 as is shown in the case of a small branch at 

 d. The axis of the stem of a latent bud is 

 shown at e. 



propose to enter into the technique of the operation, merely 

 remarking that it is evident that the expense should be incurred 

 only in the case of such trees as promise to yield high-class 

 timber. With this limitation there is no doubt that as forestry 

 advances the pruning of dead branches will become general. 



