Deciduous trees shed their leaves in the fall, unlike evergreens that keep their leaves year-round. When deciduous trees are bare in winter, some people may think it's impossible to identify a particular tree, but this is not true. Because twigs are arranged in the same way as leaves, they can provide valuable clues for identifying a particular tree, according to the Nature Conservancy website. Twig identification can quickly become a fun hobby of identifying dormant trees.
An understanding of basic botanical terms helps when identifying tree twigs. "Terminal buds" refers to the tips of branches or stems. "Lateral buds" are buds that grow on the sides of branches or twigs. "Lenticels" pertains to the tiny, lightly colored openings on backs of twigs that allow for the interchange of gases between twig tissue and the atmosphere. "Leaf scar" is the scar on a twig caused by a leaf falling. "Nodes" refers to a twig's leaf-bearing joints, notes the Nature Conservancy. "Pitch" is the word used to describe the spongy tissue of a twig.
Tree twigs come in various sizes, shapes and colors. While some twigs are stout, others are thin. Some have small buds and others have large buds. For example, elm twigs are thin, hairless and have a somewhat zigzag shape, with a reddish-brown color and buds more than ¼ inch long, notes the University of Vermont. White oaks twigs, which are shiny, reddish-brown or gray, have small, hairless, rounded buds.
Opposite twig arrangements have twigs arranged in pairs, located directly across from each other. Examples include dogwoods, ashes, maples and chestnuts, notes the University of Kentucky. Rather than being directly across from each other, alternate twigs are staggered. Trees with twigs in alternate arrangements include oaks and elms. Some trees have a whorled arrangement in which three or more twigs shoot out at the same point. This is rare in trees, and more commonly seen in smaller plants.
Note the texture of the twig. Is it smooth, rough or stocky? There are differences between new growth and old growth. Color, taste and smell are other considerations. Check the shape, size and color of the twig's pith. Most native twig species have solid piths, while some have a pith that has disks that are elongated with regularly spaced horizontal cells. Chambered piths have empty cavities divided by cross partitions, notes Texas A&M University.
Sometimes twigs have strange, unexpected variations, such those with "corky ridges" or "wings" found on a sweet gum tree twig. It's unclear why some twigs have such weird adaptations, but there are a few possible theories. Backyard Nature says these corky ridges are found on older twigs and may help twigs either dispel or hold heat. Another theory is that irregular adaptations hinder leaf-chewing caterpillars traveling from leaf to leaf.