70 



OHIO EXPERIMENT STATION: BULLETIN 208 



form beneath the clay if the inner bark or cambium be not entirely 

 destroyed. It is safer, however, to insert a few long scions as shown 

 in the accompanying picture. 



This is called "bridge-grafting." The sap circulation of the 

 tree, cut off by the wound made by the rodents, is resumed through 

 the scions which become a part of the tree — enlarging- and growing 

 together until, in after years, only a slight enlargement or "bulge" 

 on the trunk of the tree thus treated will be noticeable. 



In bridge-grafting, the wounds should be made clean and smooth 

 with a sharp knife and covered entirely with grafting wax. 

 The scions should be cut a trifle longer than the span to be bridged 

 so that, when they are inserted, their curving form will tend to keep 

 them firmly fixed in position. The two ends of the scions are cut 

 to a thin, wedge form. Incisions are made in the bark with a narrow 

 chisel — those above the wound sloping upward and those below slop- 

 ing downward. Insert the scions firmly and wax heavily and 

 securely all wounds made in the operation, especial care being 

 exercised to press the wax in firmly and neatly about the points of 

 union of scions with the body of the tree. The sectional drawing 

 will show more clearly than printed description the manner of 

 making the "bridge." 



RECEIPT FOR STANDARD GRAFTING WAX 



Melt together four parts (by weight) of resin, two parts of bees- 

 wax and one part of tallow. Pour the mixture into a pail or tub cf 

 cold water. As the mass begins to cool so that it can be handled, 

 grease the hands with tallow and pull and work the lump of wax 

 until it becomes quite light in color. Form into small balls or sticks 

 for convenient use. This wax will keep in good condition indefinitely. 



