How Trees Spend the Winter 



Look at the twigs of half a dozen kinds of trees, and find 

 the Httle raised dots on the smooth surface. They usually vary 

 in colour from the bark. These are leniicels, or breathing pores — 

 not holes, likely to become clogged with dust, but porous, corky 

 tissue that filters the air as it comes in. In most trees the smooth 

 epidermis of twigs is shed as the bark thickens and breaks into 

 furrows. This obscures, though it does not obliterate, the air 

 passages. Cherry and birch trees retain the silky epidermal 

 bark on limbs, and in patches, at least, on the trunks of old trees. 

 Here the lenticels are seen as parallel, horizontal slits, open 

 sometimes, but usually filled with the characteristic corky sub- 

 stance. They admit air to the cambium. 



There is a popular fallacy that trees have no buds until 

 spring. Some trees have very small buds. But there is no tree 

 in our winter woods that will not freely show its buds to anyone 

 who wishes to see them. A very important part of the summer 

 work of a tree is the forming of buds for next spring. Even 

 when the leaves are just unfolding, on the tender shoots a bud 

 will be found in each angle between leaf and stem. All summer 

 long its bud is the especial charge of each particular leaf. If 

 accident destroys the leaf, the bud dies of neglect. When mid- 

 summer comes the bud is full grown, or nearly so, and the fall of 

 the leaf is anticipated. The thrifty tree withdraws as much as 

 possible of the rich green leaf pulp, and stores it in the twig to 

 feed the opening buds in spring. 



What is there inside the wrappings of a winter bud ? "A 

 leaf," is the usual reply — and it is not a true one. A bud is an 

 embryo shoot — one would better say, a shoot in miniature. It 

 has very little length or diameter when the scales are stripped 

 off. But with care the leaves can be spread open, and their 

 shape and venation seen. The exact number the shoot was to 

 bear are there to be counted. Take a horse-chestnut bud 

 — one of the biggest ones — and you will unpack a cluster 

 of flowers distinct in number and in parts. The bud of the 

 tulip tree is smaller, but it holds a single blossom, and 

 petals, stamens and pistil are easily recognisable. Some buds 

 contain flowers and no leaves. Some have shoots with both 

 upon them. If we know the tree, we may guess accurately 

 about its buds. 



There is another popular notion, very pretty and sentimental, 

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