FRUIT TREES. Chap. IV. 69 



it will become excessively forceful & harmful to the nearby branches & sometimes to the 

 rest of the tree. 



As soon as some branches get to be much stronger than the others, they have to be 

 removed or restricted to prevent or to stop the ill effects they have on the other branches 

 & on the roots. 



Proposition 3. In nature, sap propelled by a root is carried mainly to the branches 

 on the same side as the root. 



If one side of a tree flourishes excessively & overcomes the other side, and 

 pruning can't reduce its vigor, the source of this energy undoubtedly lies in its 

 corresponding roots. So some of the strongest roots have to be exposed and cut back to 

 their origins to balance the two sides of the tree. But this drastic remedy should be used 

 only in extreme circumstances & with great care, because it sometimes happens that roots 

 don't correspond to branches on the same side, but to those on the opposite side. In that 

 case the weaker branches necessarily would be lost as a result of the operation. 



Proposition 4. Sap moves forcefully & abundantly inside a branch depending on 

 how close it is to the vertical. 



A tree tends to grow to a height typical of its species; as the vertical branches 

 alone favor its height, the tree strives to extend & and strengthen them more than the 

 horizontal ones. Additionally, the top of an espalier tree always fills out sufficiently due 

 to the tendency of the sap to rise up to it. 



So if you permit strong branches to grow up vertically, the sap will carry its 

 richness & its main activity up to them, 



