Bud, the part of a plant that develops into a leafy shoot, a flower, or both. The leaf bud consists of a small, pointed shoot surrounded by rudimentary leaves. As the bud opens, the tiny shoot and miniature leaves develop into the stem and foliage leaves. Flower buds are structurally similar to leaf buds and develop in much the same manner. Mixed buds, which give rise to both leafy shoots and flowers, develop in some plants such as the apple, blackberry, and pear.
Buds that grow at the ends of stems are called terminal buds. As they open, the stem increases in length. Branches form by means of lateral, or axillary, buds, which develop at the base of the leaf stalk where it joins the main stem. Stem, illustration titled A Typical Stem.) Adventitious buds are buds that form on parts of the plant other than at the base of a leaf stalk—roots, stems, and even leaves.
Plants growing in warm regions usually have naked buds (buds without an outer covering). The buds of perennial plants growing in cold regions are usually protected during winter by small leaves called bud scales. These scales help prevent the bud from drying out, and protect it from injuries, disease-causing organisms, animals, and excessively low temperatures. Bud scales are sometimes covered by hairs, wax, or resinous substances for added protection. In the spring, the bud scales fall off and the young leaves unfold.