. 32 



ted period, and then die. All unions, there- 

 fore, between widely different genera and 

 species, are utterly impossible, as the graft 

 cannot live upon the sap supplied by the 

 stock, any more than a lion can be fed upon 

 grass. Virgil, and other writers of antiquity, 

 being ignorant of this principle, were led into 

 great errors a warning to those of modern 

 times, who publish dreams of imagination in- 

 stead of real facts. 



The practical limits within which grafting 

 is ordinarily confined, are, first, between vari- 

 eties of the same species, for standards; and 

 secondly, between varieties of different species 

 or genera, for dwarfs. The Apple upon an 

 Apple-seedling, is an example of the first, the 

 Apple upon the Pear, and the Pear upon the 

 Quince, are examples of the second. Other 

 things equal, grafting is successful in propor- 

 tion to the health and vigor of the stock upon 

 which it is performed. Recently transplanted 

 trees, therefore, are not in a favorable situation 

 to be grafted, although they often are grafted 

 successfully. 



The primary object of grafting has already 

 been stated. Among the secondary uses of 

 this curious and very ancient art are, 



