WHEN TO PRUNE 107 



the wounds which are not reported in these pic- 

 tures. 



We are forced to conclude that some factor 

 other than season is the most important in de- 

 termining the healing of these wounds. It re- 

 quires but a superficial examination of the pic- 

 tures to show that these important factors are 

 two, the position of the wound in the tree, 

 and the length of the stub ; and of these the 

 former is the more important. Wounds on 

 strong limbs, especially those which are vertical 

 or ascending, heal best (compare Fig. 89, Fig. 

 90, and e, i, j, k, 1, in, w, y). Very long stubs die 

 back, instead of healing (see n, o, p). Wounds 

 lying close to the -parent branch heal best, and 

 those cut beyond the bulge or shoulder are inter- 

 mediate between these and the very long stubs. 

 (Compare, in the first category, Fig. 89, b, bb, 

 bbb, c, cc, ccc, ddd, e, i, j, k, 1, m, w, y, z; and 

 in the second category, d, dd, f, h, q, r, s, t, v, x, 

 zzz.) 



Three of the wounds were made when the wood 

 was solidly frozen. Of these, bb is healing well, 

 showing that pruning when the wood is frozen 

 does not of itself delay the healing process. 

 (See Section 3, Chapter IV., for a further dis- 

 cussion of this question.) Wounds o and zzz 

 are not healing well, but the reason is to be sought 

 in the position and nature of the wound, not in the 

 fact that the wood was frozen at time of cutting. 



