leaves are, therefore, branches.—The buds at _bbbb_ have no leaves, and they remain the same size that they were a year ago. They are dormant. The only way for a mature bud to grow is by making leaves for itself, for a leaf will never stand below it again. The twig, therefore, has buds of two ages,—those at _bbbb_ are two seasons old, and those on the tips, of all the branches (_aaaa_, _h_), and in the axil of every leaf, are one season old. It is only the terminal buds that are not axillary. When the bud begins to grow and to put forth leaves, it gives rise to a branch, which, in its turn, bears buds.—It will now be interesting to determine why certain buds gave rise to branches and why others remained dormant. The strongest shoot or branch of the year is the terminal one (_fh_). The next in strength is the uppermost lateral one, and the weakest shoot is at the base of the twig. The dormant buds are on the under side (for the twig grew in a horizontal position). All this suggests that those buds grew which had the best chance,—the most sunlight and room. There were too many buds for the space, and in the struggle for existence those that had the best opportunities made the largest growth. This struggle for existence began a year ago, however, when the buds on the shoot below _f_ were forming in the axils of the leaves, for the buds near the tip of the shoot grew larger and stronger than those near its base. The growth of one year, therefore, is very largely determined by the conditions under which the buds were formed the previous year. _Other bud characters._ =125.= It is easy to see the swelling of the bud in a room in winter. Secure branches of trees and shrubs, two to three feet long, and stand them in vases or jars, as you would flowers. Renew the water frequently and cut off the lower ends of the shoots occasionally. In a week or two the buds will begin to swell. Of red maple, peach, apricot, and other very early-flowering things, flowers may be obtained in ten to twenty days. =126.= The shape, size, and colour of the winter buds are different in every kind of plant. By the buds alone botanists are often able to distinguish the kinds of plants. Even such similar plants as the different kinds of willows have good bud characters. =127.= Distinguish and draw fruit-buds of apple, pear, peach, plum, and other trees. If different kinds of maples grow in the vicinity, secure twigs of the red or swamp maple, and the soft or silver maple, and compare the buds with those of the sugar maple and the Norway maple. What do you learn? [Illustration: FIG. 157.—BUDS OF THE HICKORY.] CHAPTER XVI BUD PROPAGATION