PREVENTION AND REPAIR OF MECHANICAL INJURIES 145 



In spring when the buds begin to swell the grafting 

 should be done. The operation is performed as follows : 

 The injured, and perhaps dry bark, on both upper and 

 lower edges of the wound is pared back to living tissue. 

 .Several cions are cut long enough to extend a little be- 



FIG. 104— LIVING WOOD BRACE BETWEEN TRUNK AND LIMB OF NORWAY 

 MAPLE. SHOULD HAVE BEEN MADE HIGHER UP TO BE STRONGER 



yond these trimmed edges, and inserted beneath the 

 bark both above and below, thus making little "bridges" 

 across the gap. The ends of the cion are cut obliquely, 

 to insure fitting of the cambium layers of cions and trunk. 

 It is often a help to bow the cions outward slightly, be- 

 cause the spring thus formed aids in holding them in 

 place. But these and other minor details may be left to 

 individual preference. If placed an inch or so apart 

 around the trunk, enough cions should succeed to save 

 the tree. Both wound and cions should be completely 

 covered with grafting wa.x, preferably made warm so as 



