The buds that appear on roots are unusual or abnormal,—they occur only occasionally and in no definite order. Buds appearing in unusual places on any part of the plant are called adventitious buds. Such usually are the buds that arise when a large limb is cut off, and from which suckers or water-sprouts arise.
Fig. 144.—Opening Pear Leaf-bud.
How Buds Open.—When the bud swells, the scales are pushed apart, the little axis elongates and pushes out. In most plants the outside scales fall very soon, leaving a little ring of scars. With terminal buds, this ring marks the end of the year’s growth. How? Notice peach, apple, plum, willow, and other plants. In some others, all the scales grow for a time, as in the pear (Figs. [142, 143], [144]). In other plants the inner bud scales become green and almost leaf-like. See the maple and hickory.
Fig. 145.—Opening of the PEAR-BUD.
Sometimes Flowers come out of the Buds.—Leaves may or may not accompany the flowers. We saw the embryo flowers in Fig. [138]. The bud is shown again in Fig. [142]. In Fig. [143] it is opening. In Fig. [145] it is more advanced, and the woolly unformed flowers are appearing. In Fig. [146] the growth is more advanced.
| Fig. 146.—A single Flower in the Pear cluster, as seen at 7 A.M. on the day of its opening. At 10 o’clock it will be fully expanded. | Fig. 147.—The opening of the Flower-bud of Apricot. | Fig. 148.—Apricot Flower-bud, enlarged. |
