Even when the flowers and leaves disappear from the crabapple tree (Malus spp.) in winter, examining the twigs helps reveal its identity. Botanically identical to apples, crabapples differ from them only in the size of the fruits, remaining 1/2 inch or less in diameter. In the growing season, the twig is lined with green oval leaves with small serrated edges.
The smooth young bark on crabapple twigs range in color from powdery gray to a blended gray-brown. The youngest reaches of the twig, where elongation occurs, often are slightly hairy with minute grayish white hairs.
Small dormant buds, from which leaves emerge in spring, occur along the sides of the twig in an alternating pattern. The scaled buds are oval and gray and slightly hairy. At the tip of the twig, the terminal bud or buds are slightly larger and also hairy and gray. As winter transitions into spring, all buds swell until they reveal either flowers or leaves.
At the base of the buds on the sides of the twig, look for the leaf scar on the lower side of the bud. This is where last year's leaf petiole stem attached to the twig. Close examination of the scar reveals one to three vascular scars, which look like tiny round dots. The vascular scars mark where the main veins of the leaf stem attached to the twig and exchanged water, starches and nutrients.
Retreating back from the terminal bud of the crabapple twig reveals an area of ripped bark, a collar perhaps, transitioning from the smooth young twig to the previous year's twig growth. The further back you trace down the tree branch, the older the plant tissue and thicker the bark.
Looking at a crabapple twig in late fall or early winter may reveal lingering fruits. At the base of the dormant side buds, away from the tip of the branch, dangles a single or multiple cluster of plump or shriveled red to yellow apples. These crabapples range in size from 1/4 to 1/2 inch. By the end of winter the fruits naturally drop off, or are plucked away by hungry songbirds.