Diseases of the Plum 



337 



Under this head may be 

 grouped several quite similar 

 mechanical injuries. Some- 

 times they are caused by the 

 names; sometimes by the hub 

 of the manure cart; sometimes 

 by the ladder of a careless 

 picker. 



Such wounds are to be 

 smoothed with a sharp pruning 

 knife and, where practicable, 

 should be dressed with a good 

 coating of grafting wax. In 

 cases of extreme damage, and 

 when the tree is especially val- 

 uable, an attempt may be made 

 to graft new pieces of bark over 

 the wound. This can best be 

 done in late summer, at bud- 

 ding time, when the bark peels 

 easily; but, though more dif- 

 ficult of performance in the spring, the work has a fair 

 chance of success if carefully performed then. Full 

 directions for doing this work are given in the para- 

 graph on mice in the next chapter. 



22 



SINGLE-TREE DISEASE 



