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 Moreover, branches grow from buds: branches, therefore, should show a definite arrangement; usually, however, they do not show this arrangement because not all the buds grow and not all the branches live. (See Chaps. II and III.) It is apparent, however, that the mode of arrangement of buds determines to some extent the form of the tree: compare bud arrangement in pine or fir with that in maple or apple.

How are the leaves borne with reference to the annual growths?

The uppermost buds on any twig, if they are well matured, are usually the larger and stronger and they are the most likely to grow the next spring; therefore, branches tend to be arranged in tiers (particularly well marked in spruces and firs). See Fig. 154 and explain it.

Winter Buds show what has been the Effect of Sunlight.—Buds are borne in the axils of the leaves, and the size or vigor of the leaf determines to a large extent the size of the bud. Notice that, in most instances, the largest buds are nearest the tip (Fig. 157). If the largest ones are not near the tip, there is some special reason for it. Can you state it? Examine the shoots on trees and bushes.