CHAPTER I: THE WORK OF THE LEAVES 



The swift unfolding of the leaves in spring is always a miracle. 

 One day the budded twigs are still wrapped in the deep sleep of 

 winter. A trace of green appears about the edges of the bud 

 scales — they loosen and fall, and the tender green shoot looks 

 timidly out and begins to unfold its crumpled leaves. Soon the 

 delicate blade broadens and takes on the texture and familiar 

 appearance of the grown-up leaf. Behold! while we watched the 

 single shoot the bare tree has clothed itself in the green canopy of 

 summer. 



How can this miracle take place? How does the tree come 

 into full leaf, sometimes within a fraction of a week? It could 

 never happen except for the store of concentrated food that the 

 sap dissolves in spring and carries to the buds, and for the remark- 

 able activity of the cambium cells within the buds. 



What is a bud? It is a shoot in miniature — its leaves or 

 flowers, or both, formed with wondrous completeness in the 

 previous summer. About its base are crowded leaves so hardened 

 and overlapped as to cover and protect the tender shoot. All the 

 tree can ever express of beauty or of energy comes out of these 

 precious little "growing points," wrapped up all winter, but 

 impatient, as spring approaches, to accept the invitation of the 

 south wind and sun. 



The protective scale-leaves fall when they are no longer 

 needed. This vernal leaf fall makes little show on the forest 

 floor, but it greatly exceeds in number of leaves the autumnal 

 defoliation. 



Sometimes these bud scales lengthen before the shoot spares 

 them. The silky, brown scales of the beech buds sometimes add 

 twice their length, thus protecting the lengthening shoot which 

 seems more delicate than most kinds, less ready to encounter 

 unguarded the wind and the sun. The hickories, shagbark and 

 mockernut, show scales more than three inches long. 



Many leaves are rosy, or lilac tinted, when they open — the 

 waxy granules of their precious "leaf green" screened by these 



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