CHAPTER XXIX. 



GRAFTS. 



Grafting Comparison with cuttings Effects of environ- 

 ment Relations between scion and stock Variation 

 in grafts Grafting atid parasitistn Infection 

 Pollination Grafts -hybrids Predisposition of 

 Natural grafts Root-fusions. 



Grafting is a process which consists in bringing 

 the cambium of a shoot of one plant into direct 

 union with that of another, and is practised in 

 various ways, the commonest of which is as follows : 

 One plant^-the stock rooted in the ground, is 

 cut off a short distance above the surface of the 

 soil, and a shoot from the second plant the 

 scion cut off obliquely with a sharp knife, is 

 inserted into a cleft in the stock, so that the two 

 cambiums (and sometimes the cortex and pith of 

 each as well) are in close contact : the scion is then 

 tied in position, the wounds covered with grafting 

 wax, and the whole left until union of the tissues 

 is completed. This union depends on the for- 



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