LUTHER BURBANK 



which almost invariably bear the second year 

 from my grafting. Indeed, so universal is this, 

 that not one unfruited cion in a thousand will be 

 saved for the third year unless it possesses some 

 remarkable quality of growth, or shows peculiarly 

 prominent and rounded buds, associated with the 

 broad foliage that betokens unusual possibilities 

 of future fruit-bearing. 



The reader who has followed the accounts 

 of the long series of experiments necessary to 

 develop say an early-bearing cherry or a stoneless 

 plum will appreciate in some measure the value 

 of a system of grafting which shortens by two 

 or three years the interval between successive 

 generations. 



It will be readily comprehensible that by the 

 use of these grafting methods I have been able 

 to attain success in development of new varieties 

 of fruits in half the term of years that would 

 otherwise have been required. 



General Principles of Grafting 



The single principle that underlies all success- 

 ful grafting, is that the layer of tissue called the 

 cambium layer, lying just beneath the bark of 

 the twig, shall be brought in intimate contact with 

 the corresponding layer of tissue of the stock on 

 which it is grafted. The life-giving sap flows 

 through this thin layer of tissue only. As to the 



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