INFLUENCE OF TIIP: GRAFT UPON LONGEVITY. Y3 



a vigoixms stock, wliicli is the product of a seed ; and 

 hence possesses the elements of independent life, and 

 the power of infusing much of its own principle of 

 longevity into the engrafted scions or buds. 



It would be more nearly correct to say, that the 

 duration of a variety is limited more or less by that 

 of its original, and that any inherent disease in it will 

 be continued, in all its buds and grafts, although 

 the superior vitality of the stock may mitigate its 

 virulence, or protract its dormant 2:>eriod. 



Certainly, a settled conviction is obtaiuing among 

 pomologists, that some of our finest varieties, that have 

 been in existence for but the short time of fifty to 

 seventy years, have nearly reached the culmination — 

 as they can now only be produced, in any degree of 

 excellence, by the utmost care. 



The White Doyenne, the Chaumontel, and others, 

 are notable instances of the justice of this conviction. 

 Some localities still ju-oduce fruit of tliese varieties of 

 great beauty and excellence ; but even there, theinvis- 

 iljle hand of disease has stealthily touched their fruits, 

 and the plague-spot is appearing upon their golden 

 cheeks. 



The influence of the stock upon grafts is very 

 marked. The fruits of early summer varieties are 

 retarded in their ripening when grafted upon winter 

 varieties ; and pears that should keep until Easter, will 

 ripen in December, if the tree which produced them 

 was grafted upon a summer variety. 



Similarity in growth and color of wood, and in style 

 and color of leaf, between stock and graft, is important 



4 



