212 Principles of Plant Culture. 



Three principal kinds of grafting are in use, viz., cion 

 grafting, budding and approach grafting. 



386. Cion Grafting is used in grafting on roots (root- 

 grafting) and very often in grafting on the stem, espe- 

 cially on large trees. The cion is a portion of the dor- 

 mant stem, of the variety it is desired to propagate. It 

 should generally be of the preceding season's growth and 

 should always contain one or more healthy leaf-buds* 

 (132). Oions are usually cut in autumn or during mild 

 weather in winter or early spring, and are commonly stored 

 until needed for iise, in a cool cellar packed in moist saw- 

 dust, moss or lea^•es. In climates of severe winters, they 

 should always be cut in autumn. C'ions should not be 

 kept SCI moist as to cause swelling of the buds or the for- 

 mation of callus (73), nor so dry as to cause shriveling. 



In cion grafting, the proximal end of the cion (116) 

 is joined to the distal end of the stock in svich a ^\■ay 

 that the cambium layers of the two coincide in at least 

 one place. Cion grafting in the open air is usually most 

 successful when performed just before or during the 

 resumj)tion of active growth in spring, and the cion is 

 thought to unite more readily if in a slightly more dor- 

 mant condition than the .stock, possibly owing to its more 

 ready absoriDtion of water when in this state. 



The joints made in cion grafting are generallj^ coated 

 with a thin layer of grafting-wax to prevent evaporation 

 and to keep out water. Sometimes the whole exxjosed 

 part of the cion is waxed. 



387. To make Grafting-Wax for cleft-grafting (392), 

 melt together four parts, by weight, of unbleached rosin, 



* Flower-buds are occasionally used, but should be avoided except in 

 special eases. 



