200 On the Effects of different Kinds of Stocks in Grafting. 



ture to hope, that my experience enables me to draw a few 

 conclusions, which may prove useful. 



Whenever the stock, and graft, or bud, are not perfectly 

 well suited to each other, an enlargement is well known 

 always to take place at the point of their junction, and gene- 

 rally to some extent, both above and below it. This is par- 

 ticularly observable in Peach trees, which have been grafted, 

 at any considerable height from the ground, upon Plum 

 stocks ; and it appears to arise from obstruction, which the 

 descending sap of the Peach tree meets with in the bark of 

 the Plum stock; for the effects produced, both upon the 

 growth and produce of the tree, are similar to those which 

 occur when the descent of the sap is impeded by a ligature, or 

 by the destruction of a circle of bark, in the manner recom- 

 mended by Mr. Williams in a former volume of the Horticul- 

 tural Transactions.* The disposition in young trees to pro- 

 duce and nourish blossom buds and fruit, is increased by 

 this apparent obstruction of the descending sap ; and the fruit 

 of such young trees ripens, I think, somewhat earlier than 

 upon other young trees of the same age, which grow upon 

 stocks of their own species ; but the growth and vigour of 

 the tree, and its power to nourish a succession of heavy 

 crops, are diminished, apparently, by the stagnation, in the 

 branches and stock, of a portion of that sap, which, in a tree 

 growing upon its own stem, or upon a stock of its own spe- 

 cies, would descend to nourish and promote the extension of 

 the roots. The practice, therefore, of grafting the Pear tree 

 on the Quince stock, and the Peach and Apricot on the Plum, 

 where extensive growth and durability are wanted, is wrong ; 



* Vol. i. page 108. 



