MUST COME INTO CONTACT, 337 



similarly modified, in order to unite readily and firmly j and 

 also, that, although the cellular horizontal system, through 

 which union hy the first intention takes place, may be alive on 

 all parts of the section of a branch, yet that it is in the bark, on 

 the surface of wood, and in the space between the bark and 

 wood, that its development is most rapid, and its tendency to 

 growth most easily excited and maintained. 



Nor are these the only circumstances to which it is neces- 

 sary to attend, in order to ensure the success of these 

 operations. It has abeady been seen (p. 267), that the 

 youngest buds of the Potato are more excitable than those 

 more completely matured ; and the same appears to be true of 

 the buds in other fruits. 



"The mature bud," says Mr. Knight, "takes immediately 

 with more certainty, under the same external circumstances : it 

 is much less liable to perish during winter ; and it possesses the 

 valuable property of rarely or never vegetating prematurely in the 

 summer, though it be inserted before the usual period, and in 

 the season when the sap of the stock is most abundant. I have, 

 in different years, removed some hundred buds of the Peach- 

 tree from the forcing-house to luxuriant shoots upon the open 

 waU ; and I have never seen an instance in which any of such 

 buds have broken and vegetated during the summer and 

 autumn ; but when I have had occasion to reverse this process 

 and to insert immature buds from the open wall into the 

 branches of trees growing in a Peach-house, many of these, 

 and in some seasons all, have broken soon after being inserted, 

 though at the period of their insertion the trees in the Peach- 

 house had nearly ceased to grow." Hort. Trans., iii. 136, 



This property was turned to practical account by Mr. Knight 

 in budding the Walnut. Owing to the excitability of its buds, 

 this tree is diflScult to work, because its buds exhaust aU their 

 organizable and alimentary matter before any adhesion can be 

 formed between themselves and the stock ; but by taking the 

 small, fully matured, and little developed buds, found at the 

 base of the annual shoots of this plant, time is given for an 

 adhesion between them and the alburnum before they push 

 forth, and then they take freely enough. 



