XXIV INTRODUCTION. 



downwards upon which the whole success of the prac- 

 tice depends. Secondly, great care should be taken, in 

 raising the bark of the stock for the insertion of the 

 bud, that the cambium be not disturbed or injured. 

 The cambium is a secretion between the wood and 

 bark, not only destined to support the descending fibres 

 of the buds, but also to generate the new cellular sub- 

 stance within which the descending fibres are finally 

 found imbedded. If, in the preparation of the bark for 

 receiving the bud, this cambium be injured or disturbed, 

 it becomes much less capable of effecting the cohesion 

 that is necessary, than if uninjured. In budding, there- 

 fore, the bark should be carefully lifted up, and not forced 

 from the wood with a bone or metal blade, as is usually 

 the case ; for although it is no doubt true, that an opera- 

 tion clumsily performed will often succeed, yet it should 

 be remembered, that if skilfully managed it would be 

 attended with much more perfect success; and that a 

 habit of constantly operating with delicacy will enable a 

 gardener to succeed with certainty in cases in which a 

 bungling practitioner would be sure to fail. Little do 

 those who crush with rude hands the tender limbs of 

 plants, reflect how delicate is that organisation upon 

 which the life of their victim is dependent. 



Transplanting is, perhaps, that operation in which the 

 greatest difficulty is generally found to exist, and in 

 which the causes of success or failure are often the least 

 understood. Volumes have been written upon the sub- 

 ject, and the whole range of vegetable physiology has 

 been called in aid of the explanation of the theory ; 

 yet I am much mistaken if it cannot be proved to 

 depend exclusively upon the two following circum- 

 stances : 1. The preservation of the spongioles of the 

 roots ; and, 2. The prevention of excessive evapora- 

 tion. 



It is well known that plants feed upon fluid contained 



