HOW WOUNDS HEAL 137 



or nearly horizontal limbs. Contrary to popular belief 

 that it is not wise to prune limbs that are frozen solid, ex- 

 periments have shown that the mere frozen condition has 

 no influence except, perhaps, as noted by Lewis (159). As 

 a summary of all the experiments as to season of pruning, 

 it may be said that the best time to prune is during the 

 six or eight weeks that precede the resumption of growth 

 in spring. 



124. How to remove large limbs. Next to making a 

 wound in the correct position is the importance of mak- 

 ing the surface smooth ; for a smooth surface will not 

 favor the development of fungi and bacteria to the same 

 extent as will a rough or splintered surface. It is folly 

 to remove a large limb with one cut, even if that cut is 

 made in the ideal position. The leverage of the limb will 

 surely split, splinter or tear the trunk more or less seri- 

 ously (Figs. 89, 92). Safety lies in making three cuts, the 

 first on the lower side of the limb and at a distance of a foot 

 or more from the main trunk, the second on the upper or 

 opposite side of the limb and close to the first cut (Fig. 

 90), the third close to the trunk where the final wound is 

 to be (Figs. 91, 93). In making the first cut it will not 

 be long ere the saw will bind or stick. When this occurs 

 the second cut is started. Often before the second cut 

 reaches the first the limb will fall, leaving a stub which 

 can be easily removed at the proper point when the third 

 cut is made close to the trunk. 



