There’s something special about West Virginia’s mountain landscapes in the winter. As autumn fades, denuded trees provide a glimpse beneath the canopy, revealing the intimate contours of the hills and hollows. The mountains take on a distinct appearance with far more dimension, depth, and detail than that of summer. The vivid gradient of winter sunsets produces scraggly silhouettes of barren crowns stretching to greet glinting stars. Rime ice encases every twig, displaying the intricate and highly varied patterns in which plants grow. Powdery snow blends these features, giving a cozy feel to the frozen forest.
As humans, our inherent admiration of nature inspires us to understand our wild surrounding. The dormancy of winter grants clarity to a once jungled environment. The lack of leaves shifts attention to other forest features, present year-round but accentuated in the cold. “I see the trees and twigs differently,” says Andy Dalton, head of the Canaan Valley Chapter of the Master Naturalists of West Virginia. “Nothing is as simple as it looks.”
In West Virginia, there are over 100 species of native trees, presenting a formidable challenge for those seeking to tell them apart. But with close observation and time, trees become more readily recognized. “Every tree is a face to me,” says Kevin Moore, a forest ranger with the Maryland Forest Service, “like knowing a friend.”
Leaves are the primary feature used to identify trees, but they aren’t always reliable attributes. Deciduous trees drop their leaves in the winter. Leaves can also be difficult to observe when the closest branches are high in the canopy, or when various trees appear intertwined on a distant slope. Along with temporal and spatial challenges, a single tree can produce drastically different leaf forms, like the classic egg, mitten, and ghost-shaped leaves of the sassafras (Sassafras albidum). In contrast, trees of different species can produce very similar looking leaves, such as black birch (Betula lenta) and American hornbeam (Carpinus caroliniana).
Bark is another critical feature from which naturalists distinguish species. Bark can take many forms and textures from smooth to scaly and flaky to furrowed. Some species have such distinct bark that this feature alone can be used for identification. Hackberry (Celtis occidentalis) has warty bark, created from stacked puzzle-piece flakes. Long, shaggy strips of bark are unique to shagbark hickory (Carya ovata). Like any feature, bark can vary in appearance depending on the age of a tree as well as the location and conditions in which it grows.
The overall shape of a tree provides additional ID clues. These features are more easily seen during the winter when leaves are absent. “You can see the bark and crown of the tree more clearly, and you can see if it has alternate or opposite branching,” says Moore. Branching pattern is one of the easiest ways to narrow down the pool of potential species because opposite branching is far less common than alternate branching. Trees with opposite branches can be remembered using the mnemonic device: MADCapHorse. The overall shape of the tree can also be used to tell species apart, especially from a distance. Elm trees have a distinct vase-shaped form, whereas sugar maples have a distinctive, broad crown.
Cap for shrubs and vines in the Caprifoliaceae family (honeysuckle and Viburnum)
Horse for horse chestnut and buckeye trees.
Shape of an elm (left) and sugar maple (right).
An inch-long twig often has enough characteristics to identify a species. Traits such as terminal buds (buds on the tip of every twig where growth occurs) and leaf scars (where a leaf was previously attached to a twig) can be excellent indicators. Stipule scars occur just above leaf scars and indicate points where leaf-like structures were attached. Black walnut (Juglans nigra) twigs have a distinct “monkey-face” leaf scar pattern. Tulip poplar (Liriodendron tulipifera) twigs have duck-bill-shaped terminal buds and stipule scars that encircle the twig.
In addition to physical characteristics, it’s helpful to know in which environment a particular tree species grows. “You’re not going to find a lodgepole pine growing in the east or a sugar maple growing on a dry, south-sloping mountain,” says Moore. Environmental determinants can range from water and soil content to shade availability and elevation. The native red spruce (Picea rubens) typically occurs at elevations above 3,500 feet in the Allegheny Mountains.
Interested in learning more about winter tree identification? Take a winter tree ID class through the Master Naturalists program in West Virginia, check out Trees of West Virginia by Ray R. Hicks and Bark: A Field Guide to Trees of the Northeast by Michael Wojtech, or search for some winter tree keys online that use twig characteristics.
Nikki Forrester, PhD, is associate editor of Highland Outdoors and loves trees—can you tell?