GRAFTING. 



CHAPTER VI. 



GRAFTING. 



The object of grafting is the propagation of a plant by 

 fixing it on another plant called a graft bearer, which 

 furnishes it, by means of its roots, with the nourishment 

 necessary to its life. The graft-bearer is termed stock, and 

 the fragment to be propagated is called the scion. 



Grafting, like other methods of multiplication by segmen- 

 tation, insures the preservation of all the qualities belonging 

 to the scion ; the stock can only influence the scion in-so-far 

 as vigour and development are concerned, but special 

 properties, such as the constitution of the flowers, colour, 

 shape, and taste of fruit for instance, cannot be modified. 

 Sometimes the size and the saccharine strength of the grape 

 are increased; this happens even if a variety is grafted 

 on its own roots. All that has been alleged with regard to 

 the sterility of scions grafted on unfertile stocks, the altera- 

 tion in the taste of fruit of European varieties grafted on 

 American species having foxy grapes, or of the non-affinity 

 between stocks with white fruit and scions with black 

 grapes is quite erroneous, and must be regarded as simply 

 dictated by ignorance. The same thing applies .to the stock 

 which, when grafted with another variety, never modifies 

 the nature of its roots or stem tissues. 



Grafting can only take place between plants belonging 

 to closely related botanical families ; with regard to vines, 

 the limit of affinity seems to remain within the genus. 

 Inter-grafting of the different species of the genus Ampe- 

 lopsis, as also of the genus Cissus and Ampelocissus, has 

 always failed, and a fortiori also when the grafting of vines 

 on plants belonging to other families (mulberry, whortle- 

 berry, blackberry, clematis) was tried. Even the V. 

 rotundifolia, with its peculiar characteristics, does not knit 

 with other species of the same genus. 



The knitting which unites stock and scion is effected by 

 the contact of the generative layers, the tissues of which 

 unite and become modified for that purpose. The sur- 

 rounding conditions necessary for the performance of this 



