224 



PRUNING 



B C 



FIG. 203. Twigs pruned, 



Wounds and their Healing. The 



removal of a branch exposes the stem 

 tissues, and makes an opening where 

 destructive organisms, which may 

 injure or even destroy the plant, can 

 enter. Unless wounds are quickly 

 healed over, the plant will suffer. 



Since tissues that are much spe- 

 cialized, such as wood and corky 

 bark, have lost their ability to grow, 

 the meristematic tissues or cambiums 



showing the cuts at different dis- must be depended upon to heal the 



tances from the bud A, the cut wound Jf he conditk)ns are fayor . 



is too far from the bud. B, the . 



cut is so near the bud that the able for growth, the cambiums and 



bud is probably injured. C, the the cells newly formed from them 



cut is at the proper distance from develop a mass of tissue known as 



the bud. Why are the cuts made the ca u us ^ wmc h spreads over the 



wound and forms a cap-like covering. 

 The development of the callus depends very much upon the 



nature of the wound and 



where it is made. The cut 



should be made with a sharp 



tool, and so made that the 



stem will not be split. When 



a small branch is cut off, the 



cut should be made just above 



a bud, as shown in Figure 203, 



so that the leaves developed 



from this bud will supply food 



for the formation of the callus. 



If the wound is too far above 



a bud, or if the cut is so close 



that the bud is destroyed, 



then there will be a dead 



stump which will not heal. 



Side branches should be FIG. 204. An example of bad prun- 



pruned close to the main mg, showing the dead stubs of branches 



which may lead to the destruction of 



branch, so that the cambium the tree After Bailey< 



of the main branch can heal 



the wound. In Figure 204 is shown an example of improper 



