74 PRINCIPLES OF PLANT CULTURE 



vigorous young plants than in old ones; in the main, 

 central shoot than in the branches, and when growth is 

 well started in spring than during its decline in autumn. 

 The diameter of young internodes that are not unduly 

 shaded is generally in proportion to their length, hence 

 rapidly-growing shoots are usually thicker than slower- 

 growing ones. We can judge of the comparative vigor 

 of nursery trees by observing the length and diameter of 

 the internodes. 



118. The stem elongates fastest just behind the 

 growing point (66), and at least in young plants, just 

 behind the primary original growing point .(55). When 

 we desire to check the growth of the stem, therefore, we 

 remove the terminal growing point by pinching (416). 



119. Pinching stimulates branching because removing 

 the terminal growing point stimulates the development of 

 other growing points farther back (104). 



