LUTHER BURBANK 



grafting, as applied to different varieties of plants, 

 will be detailed in a moment. But first I wish to 

 consider very briefly the mutual influence that 

 cion and stock exert upon each other. 



That there is an intimate chemical and vital 

 relation between the immediate living surfaces of 

 stock and cion admits of no question. The very 

 fact that we cannot cause plant tissues to make 

 union unless they are of allied species, is in itself 

 sufficient proof of this. Moreover, the fact that 

 the cion must receive its entire supply of water, 

 conveying all nourishment except carbon (which 

 is drawn from the air) through the medium of 

 the tissues of the stock, suggests that there must 

 be a uniformity of chemical composition between 

 the two that might be supposed to amount almost 

 to identity; particularly after the cion has been 

 in place for a term of years, and has grown from 

 a tiny twig to a large limb. 



Yet, in point of fact, there is abundant evidence 

 that the cion maintains its original identity of 

 character from first to last. This may be more 

 readily understood when we know that all plant 

 food is developed within the foliage. To be 

 sure the roots supply water, the universal 

 solvent and transportation agent of all life, and 

 small quantities of certain minerals and organic 

 substances in solution, but these are not digested 



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