HEALING OF LARGE WOUNDS 189 



of the Cascades. Trees on the west of the mountains 

 should be treated a little differently. In most sections on 

 the west side, and especially in the warmer valleys, trees 

 make an extraordinary wood growth. It is no uncommon 

 thing to find young prunes and cherries making a growth 

 of six to ten feet in a single season. The excessive mois- 

 ture in soil and atmosphere, and the mild climate, are con- 

 ducive to this rapid growth. Trees grow late in the 

 season, and there is some difficulty in securing thoroughly 

 ripened wood. To cut back severely in winter aggravates 

 the evil, and more and longer wood is the result. The 

 way to check this excessive growth is to resort to sum- 

 mer pruning and pinching and even to root-pruning. 



18. The healing of large wounds is influenced 

 chiefly by the kind of plant, the general 

 vigor of the plant, their position on the 

 plant, the length of the stump, and the 

 character as to smoothness or roughness 

 of the surface ; other factors are the 

 healthfulness of the ivood, and the sea- 

 son in which the cut is made. 



These questions have been considered in detail 

 in Chapter III. Theoretically, the best time to 

 make the cut, so far as healing is concerned, is 

 in the early part of the growing season, for the 

 healing process then begins without delay; but 

 other factors exert much greater influence than 

 the mere season of cutting. Wounds on pome- 

 fruits (apples and pears) heal more readily than 

 those on stone-fruits. Those on the common 

 shade and timber trees (except pines and spruces) 

 usually heal very quickly. 



