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XXXII. ON THE EFFECTS OF DIFFERENT KINDS OF STOCKS IN 



GRAFTING. 



[Read before the HORTICULTURAL SOCIETY, February 6th, 1816.] 



THE practice of propagating fruits of different species, by grafting upon 

 stocks of other species, has been so extensive, both in ancient and modern 

 times, that the good and ill effects of it can scarcely be supposed to have 

 escaped the observation of gardeners. Accurate information upon this 

 subject can, however, only be acquired by experiments accurately made, 

 and closely attended to, during many successive years, upon the com- 

 parative good and ill effects of stocks of different species, when growing 

 in soils of the same, and of different qualities : and no such experiments, 

 have, I believe, ever been made in this country, nor, to a proper extent, 

 in any other. Duhamel has pointed out, with his usual ability, the 

 erroneous opinions entertained by his countrymen upon this subject, and 

 has given some valuable information ; but he admits, that relatively to 

 some very important points, he only details the opinions of others ; and 

 he laments that he has not himself made the experiments necessary to 

 decide the questions, which he wishes to investigate. I also feel, that I 

 am not, by any means, master of the subject upon which I have taken 

 up my pen to write : but I believe that I have made and seen the 

 result of more experiments, during the last thirty-five years, than any 

 other person ; and I venture 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 generally to some extent, both above and 

 below it. This is particularly 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 Horticultural 

 Transactions *. The disposition in young trees to produce and nourish 

 blossom, buds, and fruit, is increased by this apparent obstruction of the 



* Vol. I. page 108. 



