220 Principles of Plant Culture. 



h— Propagation by grafting. 



383. Grafting consists in placing together two' por- 

 tions of a plant or of different plants, containing living 

 cambium (68) in such a way that their cambium parts 

 are maintained in intimate contact. If the operation 

 is. successful, growth will unite the two parts (69), 

 and plant processes will go on much as if the parts 

 had never been separated. The union usually takes 

 place most rapidly when the cambium cells are in the 

 state of most rapid division, i. e., when growth is most 

 vigorous. 



The more intimate the contact of the cambium in the 

 parts brought together, and the less injury their cells 

 sustain in adjusting them, the more likely are they 'to 

 unite. ' 



The plant that it is desired to change by grafting is 

 called the stock, and the part designed to be united to 

 the stock is called the cion (scion), graft or bud. 



Although the tissues of two plants of differing char- 

 acter often unite in grafting, each of the united parts 

 almost always retains its individual character. For ex- 

 amiple, if one or more buds of the Ben Davis apple are 

 caused to unite by grafting with the stem of a Baldwin 

 apple the parts that grow thereafter from the Ben 

 Davis, buds, though nourished by sap that has passed 

 through the Baldwin roots and stem, with rare excep- 

 tions, continue to be Ben Davis, while the parts that 

 grow from the Baldwin stock continue to be Baldwin. 

 To this fact is due the chief value of grafting, viz., it 

 enables us to chang.e the character of a plant. 



