2i GENERAL PRINCIPLES. 



all others, sliould be intelligent, will not allow themselves 

 to fall behind and perform their labors in the dark. 



Fully sensible of the importance of this preliminary 

 study, and confident that the minute and practical details 

 of culture cannot be well understood without it, I propose 

 here, before entering uj)on the main subject, to describe, 

 in as few and as plain words as possible, the structure, 

 character, connection, and respective offices of the various 

 parts of fruit trees, and the names by which each is 

 known in practice. 



Section 1. — ^Tiie Eoot. 



The Eoot is composed of several parts. 



1st, The collar {A^ fig. 1), which is the centre of gi'owth, 

 or ]3oint of union between the root and stem, usually at 

 or just below the siu-face of the ground. In root graft- 

 ing seedlings, this is the point where the graft is set. 



2d. The body or main root {Jj, fig. 1), which usually 

 penetrates the earth in a vertical direction, and decreases 

 in size as it proceeds downwards from the collar. It is 

 also called the tap root. A seedling that has not been 

 transplanted has usually but one descending or tap root, 

 furnished in all its length with minute hairy fibres. 



3d. The lateral rootsiC., fig. l)are principal divisions or 

 branches of the main root, and take more or less of a 

 spreading or horizontal direction. When seedlings are 

 transplanted, having a portion of the tap root cut ofij 

 these lateral or side roots are immediately formed. 



4th. The fibres or rootlets (i?, fig. 1) are the minute hair, 

 like roots which we see most abundant on trees that have 

 been frequently transplanted. Dift'erent species of treea 

 vary much in their natural tendency to produce fibres. 

 Thus the pear and the apple require frequent transplant- 

 ing, and often root pruning, to produce that fibrous condi- 

 tion which is necessary to great fruitfulness ; whilst the 



