92 THE TREE BOOK 



against a snowy hillside, look black rather than 

 green. Cold and frost hats changed the chloro- 

 phyll grains to a somber and dingy tint. They 

 will take on greenness with the return of the 

 sun. 



''The junipers do not look very green in win- 

 ter either," says a lover of the trees, "but their 

 subdued color is caused by the position of the 

 leaves, which have turned their backs towards 

 the beholder. In summer these leaves bristle 

 outwards 'like quills upon the fretful porcu- 

 pine. ' In winter their tips are raised and their 

 upper surfaces are dose against the stem. 

 Thus cuddled together, they may mutually help 

 to keep one another warm. Their winter posi- 

 tion is like that taken on summer nights by the 

 tender foliage of the honey locust and the sensi- 

 tive plant." 



When we break a leaf from the branch, we 

 usually tear and injure the bud to which it is 

 joined. But when Nature removes the leaf no 

 harm is done. Why? Because she first builds 

 a layer of tissue across the end of the petiole, 

 or footstalk, of the leaf. This loosens the leaf 

 and the first slight breeze carries it to the 

 ground. A waterproof sear marks its place 

 on the twig. This is a wise provision of Mother 

 Nature. Sap cannot drip from the wound, and 



