STUDIES OF SEED-PLANTS 



175 



the cambium, and allows the two branches to grow together. 

 Sometimes two trees may so 

 grow together when they are 

 small. 



The observation that stems 

 will grow together or natu- 

 rally graft probably led to 

 artificial grafting of fruit 

 trees. Essentially all graft- 

 ing consists in bringing the 

 cambium layer of a piece of 

 twig with a bud (scion) from 

 one plant into contact with 

 the same layer on stem of an- 

 other plant of the same or 

 sometimes a closely related 

 species. Various ways of 

 doing this are illustrated in 

 Fig. 51. Grafts are usually 

 placed on young plants near 

 the roots (" root-grafting") so 

 that after the graft grows and 

 the original stem is cut away, 

 only the variety of the graft 

 will be represented in the 

 stem above ground. Old 

 trees are grafted by cutting 

 off branches (" top-grafting") 

 and inserting scions or grafts. 

 If a new branch grows below 

 the graft, it will bear fruit of 

 the original variety. 



Budding is essentially the 

 same as grafting, but a single 

 bud with a slice of bark (Fig. 



FIG. 51. Upper row whip- or 

 tongue-grafting, a, stem or stock ; 

 6, scion or graft ; c, united and 

 wrapped. Middle row cleft 

 grafting, a, scion ; 6, two scions 

 inserted in cleft ; c, waxed. Lower 

 row budding. a, stem cut to 

 receive bud (6); c, bud inserted 

 beneath bark ; d, wrapped. Note 

 in all the figures that cambium of 

 scion and stock meet. (U.S. Dept. 

 Agriculture.) 



