STOCK AND CION HANDLING 215 



results with riparia stocks. One and two-year rooted cuttings were 

 used in preference to plain cuttings, because of a gain of one year 

 and because a larger per cent will grow. In field practice he used 

 rooted cuttings just grafted and rooted resistant stock in alternate 

 rows. While he secured 85 to 90 per cent of the former, only 60 

 per cent of the latter grew, and these produced very few grapes the 

 year set out ; the former gave eight to eleven pounds a plant. Mr. 

 Gillett considers bench grafting resistant vines the best, cheapest 

 and quickest way to reconstruct a vineyard or start a new one. 



277. Influence of grape stock on crop. L. Ravaz, a French in- 

 vestigator, reports 28 years' consecutive yields of two varieties of 

 European grapes grafted on various American stocks. Though 

 much decadence is noted in the vines grafted on certain stocks, the 

 decline in yield and vigor is attributed to such causes as variation 

 in resistance to phylloxera (280), unseasonable weather, lack of 

 adaptation to soil, etc., rather than to influence of grafting and old 

 age. The general deduction is that under proper conditions grafted 

 vines do not deteriorate with age more than do ungrafted ones. 



273. Grafting green grape vines. In Rumania the tongue graft 

 has been successful with green wood not less than one-fourth inch 

 diameter at the point grafted, and the wood of both stock and 

 cion hard enough to be with difficulty compressed between thumb and 

 finger. The usual precautions of mature wood grafting must be 

 observed. After union the grafts may be handled like cuttings, or 

 roots may be started by layering on the stocks below the grafts. 

 The advantages claimed are : The method simplifies the operations 

 by obviating stratification of both stocks and cions ; 2, it is cheaper 

 and a larger percentage of grafts succeed ; 3, the chance element 

 is reduced to a minimum ; 4, it seems to promise greater success 

 with varieties difficult to unite when mature. 



279. Seedling vines as cions. Trabut suggests that new varieties 

 of grapes may be quickly brought into fruit by grafting the seed- 

 lings on green shoots of established vines. He has secured suc- 

 cessful results by the following method : In early June the seed- 

 lings which had only their cotyledons, were cut as for ordinary 

 cleft grafting and inserted in the tips of green shoots whose ends 

 were wrapped with small paraffined bands secured with raffia. The 

 completed grafts were then covered with paraffined paper bags to 

 preserve humidity. In about two weeks the parts united and the 

 cions grew vigorously. By October the unions were almost invisible 

 and the canes often 10 feet long. 



280. Phylloxera, a plant louse which in its nymph stage 

 feeds on roots of grapes, and forms galls on the leaves, 

 the latter being the most conspicuous sign of infestation. 

 The insect does little appreciable damage to American 

 species of grapes, hence these are used as stocks for 

 European varieties, which are so seriously attacked that, 

 except in California where the insect was unknown until 



