Wintertime Tree Identification

Being able to identify the wide variety of trees found in Frederick County can be very challenging task. This is especially true during the winter when trees have shed their leaves. Identifying leafless trees means that you have to focus on other characteristics of the tree, such as the general shape or size of the tree, the bark, the buds, branching pattern, fruits or nuts that might be present, smell, discarded leaves on the ground, location of the tree, and neighboring trees and shrubs. You can often successfully determine what kind of tree you have by the process of elimination, knowing that it can’t be acertain variety.

The most obvious tree characteristic during the winter is whether or not the tree has foliage. If the tree has foliage, it is an evergreen such as a pine, spruce, fir, cedar, evergreen holly, rhodendron, or mountain laurel. Most evergreens are easy to identify once you determine how the needles attach to the small branches. If it doesn’t have foliage, it is a deciduous tree. This could be trickier. Let’s pretend you’re trying to identify a very large tree in a nearby forest. Your first impression is that this tree has no leaves. Therefore it can’t be a pine, spruce, cedar or other evergreen.

Another useful characteristic in wintertime tree identification is observing the general shape of the tree. Trees, like people, come in all shapes and sizes. Some trees have a dominant central trunk and the branches are located on the side of this dominant leader. Some examples of these kinds of trees are poplars, pin oaks, aspen, and gum trees. Other trees have numerous large branches that come out of the main trunk so that there is no real central leader; these trees usually have a wide crown. Some examples of these trees include beech, white oak, black walnut and elm. Some trees have a very distinct outline if you look at them from a distance; for example, the drooping branches of a weeping willow or the V shape of a large elm tree.

The size of the tree may help you narrow down what you are looking at. Some trees like dogwoods, witch hazel, muscle wood, ironwood, and black haw do not grow very large. Others like red maple, persimmon, black willow, birch, and most pines are medium-sized trees. There are some trees that grow rather large at maturity like sycamore, white oak, red oak, beech, tulip poplar, and cottonwood. If the tree you’re trying to identify has a large diameter and is 100 feet tall you can be pretty sure that it isn’t a dogwood or smaller tree. So far we have been looking at our mystery tree from afar and have determined that it is a large growing deciduous tree with a wide spreading crown. We’re not quite sure what it is, but we know what it can’t be. Next we will move in for a closer look.

Credit: frederick.forestryboard.org - Mike Kay
Credit: frederick.forestryboard.org - Mike Kay

We continue our winter time quest to determine the identity of our mysterious large tree located in the adjoining woodlot. From a distance, we have narrowed down our choices. As we enter the woods we note the surrounding terrain and vegetation.

Sizing up the topography and forest cover type is important because most tree species are found in specific “ecological” communities. For example, a bottomland, floodplain area contains trees that are tolerant of wet conditions. In these areas we would normally find trees such as sycamore, silver maple, willow, green ash, river birch, and pin oak. Other trees prefer moist conditions, but they will not tolerate being underwater very long. These trees would be found on level to slightly upland areas. Examples of these trees are tulip poplar, red and white oak, pignut hickory, black walnut, white ash, and white pine. Other trees are found in steep rocky areas where there is not much soil. Some trees commonly found in these ridge top sites include chestnut and scarlet oak, Virginia and pitch pine, and black gum. Knowing a little about the “silvics” of trees will allow you to narrow down your possibilities. For example, pin oak and scarlet oaks look a lot alike but pin oaks are found in low lying areas while scarlet oaks are found in rocky uplands. So if you’re looking at a tree that is either a pin or scarlet oak at the High Knob area at Gambrill State Park, chances are pretty good that this is a scarlet oak.

Looking at the ground vegetation can also help us narrow down our choices by providing clues what type of community we are entering. For instance most oak-dominated forests have a dense leaf litter that is present year round. This is because oak leaves do not decompose quickly. If your standing in a forest that has a lot of leaves on the ground chances are most of the trees present are oaks. If on the other hand, the forest you are in surrounds a large creek or river you can bet you will find trees tolerant of periodic flooding like sycamore, silver maple, boxelder, hackberry, and black willow.

Suppose once you enter the forest you notice that it’s somewhat hilly, and there are a lot of leaves on the ground. You correctly assume that you are entering an oak forest. Next week ... let’s take a closer look at this big tree.

Let's assume that you found the large tree and walked up to it. We already know this is a large deciduous tree and that we are standing in an oak forest from our previous observations. Now we can take a closer look to narrow down our choices and finally identify this tree.

The way branches attach to the main trunk or smaller branch attachments is a helpful method of narrowing down your choices. Most trees have alternate branch attachment, meaning that if you have a large branch, the smaller side branches attach in alternate fashion. A few trees have opposite branch attachment, meaning that the branch attaches directly opposite of the other.

If you remember the phrase MAD Horse, you will know which trees are opposite -- maple, ash, dogwood and horse chestnut. If the large tree you are trying to identify does not have opposite branching pattern, you know that it can't be a maple, ash, dogwood or horse chestnut.

The relative size of the small terminal branches is another clue. Elms have small branchlets while trees such as the black walnut have very stout terminal branches. Some terminal branches can be colorful, like the boxelder, which has green branches, or the silky dogwood that turns bright red in the winter.

Another somewhat distinctive feature is the shape, texture and color of the bark. Some trees, such as beech, serviceberry, muscle wood and young maples, have smooth bark. Other trees, such as chestnut oak, black oak and black cherry, have rough bark.

Some bark is flaky, like that of river birch or shagbark hickory. Some bark has distinct patterns, like the tight v-shaped bark of the ash or walnut, or the splotchy almost camouflage pattern of the sycamore. Some bark is distinctive, like the corky ridges found on the hackberry or the shaggy bark of the shagbark hickory. Bark can also be colorful. It can vary with different shades of black, brown, tan, gray, white, green, orange, pink or red.

Looking at the mystery tree we determine that the bark is whitish to gray in color and it has long blocky strands.

The wintertime buds on a tree can be distinctive and also provides clues. Winter buds can be round (spicebush), pointy (beech) or egg shaped (basswood). There may be hairs on the bud (mockernut hickory) or they could be bald (pignut hickory). Buds can have a protective covering around them (most trees) or they could be naked so all you have is a small leaf (bitternut hickory).

There can be a wide range in the color of buds as well. Buds can be very tiny (persimmon) or quite large (black walnut). We really can't see the winter buds on our large tree without binoculars. We'll have to remember to bring them next time.

Some trees such as black locust or hawthorn have spiny thorns on them, which can be an aid to identification. Some trees have distinctive smells, especially when you peel back the bark on a small twig or leaf. Some examples of this are the distinctive citrus smell of a sassafras or spicebush, the wintergreen aroma of a black or yellow birch, or the rotten peanut scent of the ailanthus tree. Some trees have a foul odor, such as a black cherry. The nearest small twig in our tree is 50 feet above our heads, so smelling this twig is not an option.

The bark of the mystery tree.

Through our previous detective work we uncovered clues on the mystery tree. We could make an educated guess at the identity of this tree now, but are not 100 percent sure that we would be correct. Instead, let's look on the ground below the tree.

Another productive means of identifying a tree is to root around on the ground under the tree to find some discarded leaves, fruit or other tree parts. Many wintertime leaves are still present on the ground, especially around those trees that have decay-resistant leaves like oaks, beech and sycamore. Unfortunately these leaves are also mixed with surrounding trees, so you have to take an educated guess that you have the correct leaf.

Sometimes there might be some dried leaves still on the tree so you can compare what you have in hand with what still remains on the tree. Likewise, the fruits or husks of many seeds may still be present during the winter. Many times you will notice acorns, hickory nuts, walnuts, beech nuts, maple, ash or tulip poplar samaras, locust or catalpa seed pods, sumac berry clusters, the large "monkey brains" fruits of Osage orange around the base of the tree.

After some detective work, you uncover what appears to be an oak leaf with smooth leaf margins and some medium-sized, round acorns that have already begun to sprout.

To summarize, we have a large deciduous tree, with no central leader per se, located in an upland forest, dominated by oak trees, the branches are alternate, the bark is whitish-gray, and we found a round medium-sized acorn that has germinated, along with an oak leaf with smooth margins on the ground.

Knowing this, we can open up our trusty tree identification book, turn to the oaks page, and compare. Studying the guide, we determine that the tree can either be a white oak or swamp white oak. Looking around, it sure doesn't look swampy and the leaves are not hairy so it must be a white oak.

Using these clues and obtaining a good tree identification book can help guide you with tree identification. Most local bookstores and libraries have a wide assortment of books that you can utilize on your quest. Look through some and choose the book you like best.

There are also a number of excellent websites that cover wintertime tree identification. Using the search word "trees in winter" will land you right in the thick of them. Getting out in the woods with someone who knows their trees provides invaluable experience.

Also, you can visit local arboretums or hiking trails that provide guided tree tours for tree identification. A tree identification course has been recently set up at Gambrill State Park's Red Trail. Here you will find a wide variety of trees that have been identified for you with descriptive signs. Good luck and remember to bring your binoculars this time.

Article by FCFCDB member

Nature Notes for 1/9-16-23-30/2011