With the fall colors around the corner, you may be wondering how we can tell what type of trees we are working with. Even in the summer, and spring, how do you identify the trees you are looking at? Of course there are apps you can use to help identify trees. However, they aren’t always reliable. If you have the ability to use a tree identification book, you should. These books have keys. In the key, you will go through multiple options, which eventually lead you to the tree you are looking to identify.
Tree Identification Step 1; Leaves:
First, you will need to determine whether the leaves are simple or compound. Simple leaves mean that there is one leaf attached to the stem or branch. Compound leaves are several leaflets, most often with 5 or more, that form one leaf. These several leaflets are attached to one petiole, which is then attached to the stem or branch. You are going to be asked whether it is a hardwood or evergreen. The identification we are discussing is not related to evergreens.
Step 2; Leaf Arrangement:
Second, you will need to determine the leaf arrangement. There are three different options when it comes to leaf arrangement. 1st you can have an opposite leaf arrangement. This is where the leaves attach to the stems directly across from each other. 2nd you can have an alternate leaf arrangement where the leaves attach to the stem one after the other, similar to a ladder. And the 3rd arrangement is called whorled, this is where there are 3 or more leaves attached at the same point on the stem.
Step 3; Veins:
Next, you will be asked if it is pinnately, or palmately compound. Pinnately veined is where the veins on the leaf attach to the midrib separate from each other. Palmately veined is where they attach at the same point at the base of the leaf.
Step 4: Branches and Leaf Margins:
Furthermore, you may have to answer questions about the branches and how they look. Most often, the key will take you to the leaf’s edge. This is called the leaf margin. There are a few options that you can choose from to explain the leaf margin. Your options include entire, undulate, finely serrate, double serrate, crenate, and lobed. Some examples are also pictured below. An example of a lobed margin is the oak leaf. And example of an entire margin is the witch hazel leaf.
Step 5: Specifics:
Lastly, you will be asked the size and shape of the petioles. You will also be asked about fruits. You can be asked about the twig and the shape of the leaves, and bud arrangement. Questions referring to the twig may ask about the color, size, etc. The shape of the leaves can be linear, lanceolate, elliptical, ovate, cordate, etc. Examples of these are pictured above. Questions about the buds may refer to the type of bud, size, shape, color, and arrangement on the twig. These questions can be difficult to answer, but gets easier with practice.
Here is an example of what a key might look like for a common tree in the Grand Rapids area:
- Leaves simple.
- Leaves broad.
- Leaves alternate.
- Leaf is entire or somewhat undulate.
- Leaf is ovate.
- Branches don’t have spines. Fruit is small.
- Fruit is an acorn. Leaves feel leathery. …………………………….Quercus, Pg #
There are more options in between these, and you have to choose from usually 2-3 options and follow the numbers down until you reach the scientific genus name, which above is Quercus. From here, you flip to the page number provided and answer more questions.
- Deeply lobed.
- Leave lobes rounded.
- Deep sinuses near middle of leaf. (Answer: no)
3. Sinuses not as above. Branches are not corky or ridged. Nut size…. Q. alba, pg #
Tree Identification Step 6; Identified Tree:
And now you flip the page number and get to see the Characteristics of Quercus alba, otherwise known as White Oak. Information on its size, form, bark, leaves, twigs, buds, wood, flowers, habitat, distribution, and any other important characteristics about the tree can be found in the profile. You also are provided with drawings of the leaf, twig, branching and leaf arrangement, buds, fruit, etc. for reference as well!
Why Tree Identification is Important:
This is a fun experience to do when you are with your family, or even if you are walking by yourself. There are many different tree keys available, including ones that are pocket sized. We recommend getting one for Michigan trees. Here is one that we use!
In conclusion, tree identification is a very important tool. We use it to communicate among our clients, estimators, office staff, and crew. With the knowledge of tree names, we ensure that the right trees are removed, or trimmed. We also are able to determine what precautions needs to take place when it comes to removing them, or trimming them. For example, Red oaks, or Quercus rubra, cannot be trimmed when temperatures are above 50 degrees. This is because of Oak Wilt, which you can find more information on below. Next time you are on a walk, we hope you enjoy keying out some trees!