Its use extends into the winter months when the leaves are no longer present on deciduous plants. However, if the key was based on bud and twig characteristics alone, it would eliminate the possibility of dividing the plants into the several groups mentioned at the beginning of this section. In most cases, the bud characters used in this key can be determined with the naked eye. However, a hand lens will always help in identification. Bud characteristics are difficult to use from late spring to early fall when rapid growth occurs and foliage is shading twigs and retarding color development.
Buds occupy a lateral or terminal position on the stem.
The lateral or axillary buds are those that develop in the leaf axis, or directly above the leaf scar. The terminal bud is formed on the end of the twig and denotes the end of the present year's growth. Often a number of buds develop at each node. These accessory, or collateral, buds are often a plump flower bud on either side of the leaf bud. Sometimes there are one or more buds above the normal lateral bud.