The Story-Book of the Fields 



must be removed neatly, not tearing them, 

 but cutting the stalk and leaving the base in 

 its place. 



The most direct path for the progress of the 

 sap from the roots to the foliage follows the 

 vertical line from the bottom to the top. 

 Anything that disturbs this direction inter- 

 feres with the ascensional force. Thus in 

 branches with abrupt angles or sharp curves 

 the impulse of the sap is slackened, as the 

 speed of a stream is impeded by the uneven- 

 ness of its bed. Also, in a branch forced to 

 bend towards the ground the sap can only 

 progress with difficulty, since its course 

 towards the end of the branch is effected in a 

 direction contrary to that which is natural. 

 The application of this principle is easily seen. 

 If we wish to moderate an over-strong branch 

 we shall bend it towards the ground, while if 

 we have to strengthen one that is weak we 

 shall draw it up in a vertical direction. 



We may also make use of the exhausting 

 effect of fruit. The more fruit that a branch 

 bears the weaker it becomes ; for the expendi- 

 ture of sap in fruit leaves less for the produc- 

 tion of the foliage which is its strength. So we 

 shall leave as much fruit as possible on the 

 stronger side and suppress it on the other. 



142 



