GRAFTING. 



95 



the sections should coincide, not leaving any part exposed 



to the air. It should be assembled in such a way as to- 



keep quite rigid without the aid of a 



ligature. Whip-tongue grafts, which 



can only be made to coincide with the 



aid of a ligature, rarely give good 



knittings ; in this case the ligature 



simply serves to prevent the displacement 



of the joint in case of knocks. 



About one-fifth of an inch is the 

 minimum diameter for a stock to be 

 grafted, the operation being rendered too 

 difficult if it is smaller. The maximum 

 diameter is limited by that of the scion. 

 However, it is possible to graft with this 

 method a stock larger than the scion, 

 but the beneficial effect of the double 

 knitting is then lost ; two to three eyes 

 are left on the scion ; this depends on 

 the length of the internodes. However, 

 in the case of grafted cuttings, one bud 

 only is left, so as to keep a certain pro- 

 portion between the outside growth and 

 the development of the roots at the start, 

 and avoid the desiccation which would 

 result from the evaporation caused by 

 too large a number of leaves. 



The whip-tongue graft, which generally enables growers 

 to replace European vineyards by American vines within a 

 year, gives the best results with regard to the proportion of" 

 knittings and the constitution of the plants. This seems to 

 be due to the large area of the surfaces of contact, which 

 allows better knitting, facilitates the exchange of food 

 material between stock and scion, and forms a long and flat 

 cicatrice, which does not injure the ultimate development of 

 the plant. The whip-tongue graft, on account of these advan- 

 tages, will always be the most used in reconstitution of 

 vineyards, as soon as the number of operators capable of 

 performing it increases. 



The Champin Graft (Fig. 54) is only a modification of the 

 whip-tongue; it is more difficult to perform ; it gives less satis- 

 factory knittings, for a part of the section is exposed to the air; 

 and, moreover, it facilitates the growth of roots on the scion.. 



Fig. 53. - Whip-tongue 

 graft with short bevels. 



