124 THE HEALING OF WOUNDS 



Among the most difficult wounds to treat are 

 the rotten cavities following careless pruning. 

 Such a cavity is seen in Fig. 71. The decay has 

 often progressed so far that it cannot be checked, 

 The things to be done are to remove all diseased 

 tissue and then to close the cavity. Cut out the 

 rotten and discolored tissue with a knife or bore 

 it out with an auger. Then soak it with an 

 antiseptic. Now drive a plug of wood tight into 

 the hole (A, Fig. 104), paint the surface, trim the 

 edges of the wound to live tissue, and let nature 

 take her course. Large wounds 

 are sometimes covered with tin 

 or zinc. This is good as far as 

 it goes, but the diseased tissue 

 should first be removed. It is 

 impossible, however, to cover the 

 wound so tight with the metal as 

 to keep out germs. If the cavity 

 is securely plugged, and the sur- 

 104. Plugging face smoothed and kept painted, 

 the results will usually be better. 

 What is to be done in such a case as Fig. 105? 

 It would probably be best to cut off the limbs at 

 A and B, and allow the remaining branch to form 

 the top. In that case, the wound at A must be 

 trimmed back smooth and clean, and painted or 

 otherwise protected. It may be desirable, how- 

 ever, to save the broken part. In that case, head 

 it back, raise it into position, and bolt it fast. 



