220 



PRINCIPLES OF PLANT CULTURE 



Tongue-grafting is also considerably used in some cli- 

 mates of severe winters, in top-grafting or " top-work- 

 ing " apple trees in the nursery, in order to give certain 

 slightly-tender varieties the benefit of an especially 

 hardy stock. This grafting is performed on two- or three- 

 year-old trees, that have been grown from root grafts. 

 The trunk is cut off at the height it is desired to form 

 the head of the tree, and a cion of the variety to be prop- 

 agated is inserted; or several cions are inserted in as 

 many branches. The latter method, while more expen- 



FiG. 114. — Shaping the cions for root-grafting. A, making the "long 

 cut" ; B, cutting the "tongue" ; C, cutting off the cion. These posi- 

 tions, and the movements they indicate, are adapted to rapid work. 



sive, has the advantage of giving to the top-grafted trees 

 the branch formation of the stock, which is sometimes 

 important. 



As growth starts on the top-grafted trees, shoots that 

 push out from the stock should be rubbed off to prevent 

 them from robbing the cions of nourishment. 



391. Root-grafting is commonly performed in-doors in 

 winter. The stocks are small trees, grown one or two 

 years from seed (seedlings). These are dug in autumn, 

 and stored as recommended for cions (386). When 

 ready for grafting, the roots are washed and trimmed by 

 cutting off the larger branch roots, after which the stem 



