72 TREATISE ON 



Proposition 7. Leaves have a considerable effect on the quantity & the movement 

 of sap, increasing or decreasing it in proportion to their number & their condition. 



If a good deal of the leaves have been removed, if insects have devoured them, if 

 they've been damaged by blight or by some other disease, the activity of the sap will 

 decline or stop; the fruit drops off & the tree deteriorates. 



So the excessive growth of a vigorous branch can be curtailed by stripping off 

 some of its leaves, that are attached like so many suckers and that supply much 

 nourishment to the branch. 



Proposition 8. The elongation of shoots is inversely related to the hardening of 

 their woody layers. 



The less hard the woody layers are, the farther out the shoot extends, & vice 

 versa. But hardening of its woody layers is slowed to the extent that it draws more sap. 

 And the sap is more abundant & active the more the shoot is oriented away from the 

 horizontal toward the vertical (4), supplied more with leaves (7), and shaded more from 

 the sun that could make it transpire & harden. 



Favoring these three causes increases elongation of a branch. Eliminating or 

 diminishing them stops or slows its progress. 



§. 1 1. Definitions. 



THERE ARE seven kinds of branches on fruit trees: wood branches, fruiting 

 branches, stunted branches, twig branches, suckers, false wood branches, and small 

 fruiting branches. 



Definition 1 . A wood branch is one that originates from the terminal bud. 



