132 GLIMPSES INTO PLANT-LIFE 



In other trees, again, the unfolding of all the 

 buds is nearly simultaneous, but in the fir tribe 

 the bud which terminates the summit of the tree 

 and is destined to form its leading shoot and 

 increase its height is developed last ; this delay 

 seems a provision of nature for the safety of the 

 most important shoot which the tree can produce, 

 ensuring its height rather than its breadth, and 

 the production of timber by the preservation of 

 its permanent trunk rather than by its temporary 

 branches. 



If a willow is deprived of the upper part of 

 its stem and so made a pollard tree, it develops 

 a bushy head of small stems which spring from 

 the other buds thrown out to repair the loss of 

 the central stem. This pollarding is often re- 

 sorted to in order to obtain wood of the right 

 kind for basket-making, and young ash trees are 

 thus treated, so that slender rods suitable for 

 hop-poles and tool-handles ma}- spring from the 

 lopped stem. 



When buds are found growing on any other 

 part of a plant except those just mentioned, 

 they are called adventitious buds. These may 



