Winter Tree Identification Tips
In our region, deciduous trees—those that lose their leaves during the colder winter months—dominate the forests, making tree identification more difficult. Luckily, there are other characteristics we can turn to when the temperature drops and the days get shorter.
Winter tree identification might seem daunting, but with some practice, anyone can identify any deciduous tree at any time of the year and with a greater degree of certainty. Species identification involves synthesizing multiple “clues” to arrive at an answer. Some species are very distinct and might only require one or two clues to make a positive identification, while others might require several. In this article, we’ll discuss a few different clues to consider in the winter months when confronted with an unfamiliar tree.
Bark
Though it might be tempting to rely on a tree’s bark for identification, the bark is often an unreliable indicator. Variations in appearance can occur within a species across different ages, with younger trees often having smoother and lighter bark than older trees. Additionally, even different individuals of the same species and age can look different due to permanent external effects, such as scarring or warping, and temporary external effects, such as shadows or wet bark.
That said, some species do have distinct bark. Black cherry (Prunus serotina), red maple (Acer rubrum), and American beech (Fagus grandifolia) are all fairly unique species commonly found in the Piedmont. Look for the dark, flaky bark that resembles kettle-cooked potato chips to find black cherries, the bullseyes and tic-tac-toe boards to find red maples, and the light-gray, smooth, and often-graffitied bark to find American beeches.
Buds
Terminal buds, also known as apical buds, are the buds found at the very tip of a twig and contain next year’s woody growth. These shouldn’t be confused with lateral buds, which grow along the sides of a twig and contain next year’s leafy growth, or false terminal buds, which are lateral buds that assume the role of the apical bud when the true apical bud is lost. Each species has terminal buds that are unique to it alone and, because there is less variation between terminal buds than there is between bark within a species, terminal buds are the most reliable characteristic to use for making an identification.
However, they’re not necessarily the easiest or most useful method. Different species within the same genus often have similar terminal buds. Oaks (members of the Quercus genus) are a good example of this. Additionally, given that these buds appear on the end of a tree’s branches, they are often impossible to see from the ground on live, mature trees.
Other Clues
Winter tree identification often comes down to a combination of bark, buds, and other clues. These other clues could include things like site conditions, growth form, or dropped leaves and fruits. Site conditions, as we mentioned in our Dry Oak - Mixed Hardwood Forests Spotlight, are the abiotic features of a growing site that limit what can survive there. If you’re struggling to determine whether a tree is a red maple or a silver maple (Acer saccharinum), for example, think about where the tree is growing. If it’s growing in a drier, upland site, it’s more likely to be a red maple, as silver maples have a lower drought tolerance.
Growth form refers to the shape that a tree takes on and is largely determined by branch positioning. Tuliptrees (Liriodendron tulipifera) tend to grow very straight, vertical trunks with a small canopy relative to the total height of the tree. Black gums (Nyssa sylvatica) also tend to grow straight trunks but will often have limbs growing lower on the trunk and distinctly perpendicular to it. Black walnuts (Juglans nigra), especially those growing on field edges, will often develop a forked trunk.
Finally, it can often be just as helpful to look at the ground as it is to look at the tree itself. At the base of a tree, you’ll find dropped leaves and potentially fruits, such as oak acorns or maple samaras. This gets tricky as you’ll likely find many different kinds of leaves and fruits, all in varying stages of decomposition, but this can be the last piece of evidence needed to confirm a guess.
Effectively identifying trees with the help of site conditions requires an understanding of tree growth strategies. The USDA Forest Service’s Silvics of North America is a great resource for learning about the moisture, soil type, and sunlight preferences for most native trees in North America.
Tips
Fundamentally, the only way to get better is to read and practice. Read about the site conditions, commonly-occurring trees, and the life histories of those trees in your area. The US EPA has a good map of ecoregions in the US, accompanied by detailed descriptions. These will help to establish a broad baseline of what to expect in your area. Then, look for trees you can already confidently identify and pay attention to the clues found on them. Tree identification is a skill that builds on itself and gets progressively easier as you can mentally eliminate more options. Forestry Images has an extensive collection of tree images that are vetted; look for bud or bark images of unfamiliar species there to ensure you’re looking at the right thing.
Header image photo credit: DuoTone via Pixabay.