222 



PRINCIPLES OF PLANT CULTURE 



cion contains a bud on its thicker edge. When the stock 

 exceeds an inch in thickness, two cions are usually in- 

 serted (Fig. 117), to increase the chances of 

 success. The elasticity of the stock should 

 exert sufficient pressure to maintain very close 

 contact between it and the cion; otherwise it 

 should be tightly bound with cord or raffia 

 (393). The cions should contain at least one 

 bud beyond the end of the stock. The wedge- 

 shaped cut is usually made about one inch 

 long, and the cion should be inserted into the 



FIG. 116. 



FIG. 117. 



FIG. 118. 



FIG. 116. Cion shaped ready for insertion in cleft. 



FIG. 117. Cions inserted in cleft, ready for waxing. 



FIG. 118. Cross-section in Fig. 113 (after Maynard). C cambium 

 layer of stock; C' cambium layer of cion. The cambium layers of 

 the outer edge of the cion should form a continuous line with those of 

 the stock. The cion is made a little thinner at its inner edge to per- 

 mit the pressure of the stock to be exerted at the outer edge. 



cleft as far as the length of the wedge, after which 

 all the exposed wounded surfaces, including the distal end 

 of the cion, should be coated with grafting- wax (387). 



Cleft-grafting is most used in top-grafting old trees. 

 Four to six of the main branches, located as nearly equidis- 



