One of the most common questions we hear from Detroit Lakes homeowners right now is a simple one: "How do I even know if I have an ash tree?"

It is the right question to ask. Emerald Ash Borer is confirmed in counties surrounding Becker County and moving our direction. Before you can decide whether to treat and protect your trees — or whether EAB is even a concern for your property — you need to know what you have. Here is exactly how to tell.

The Three Things That Identify an Ash Tree

Ash trees have three specific characteristics that, when you see all three together, confirm what you are looking at. You do not need any tools or expertise — just your eyes and a few minutes in your yard.

1. Opposite Branching

Look at how the branches grow off the main limb. On an ash tree, branches grow directly across from each other in matched pairs — one on the left, one on the right, at the same point on the stem. This is called opposite branching and is one of the most reliable identifiers. Most common trees in Minnesota — oak, maple, basswood — have alternating branches that stagger up the stem. Ash does not.

2. Compound Leaves

An ash leaf is not a single leaf — it is a group of individual leaflets joined along a central stalk, which then attaches to the branch. Each stalk carries five to nine leaflets depending on the species. The leaflets have smooth or very lightly toothed edges. If you pull a single "leaf" off an ash tree, what you are actually holding is an entire compound leaf with multiple leaflets attached to one stem.

3. Diamond-Pattern Bark on Mature Trees

On older ash trees, the bark develops a distinctive interlocking diamond or X-shaped ridge pattern. It is one of the more recognizable bark patterns of any Minnesota tree once you know what to look for.

If your tree checks all three boxes — opposite branching, compound leaves with five to nine leaflets, and diamond-pattern bark — you almost certainly have an ash tree.

The Minnesota DNR has a detailed visual identification guide specifically built to help homeowners confirm whether their tree is an ash: Minnesota DNR — Identify Ash Trees

Which Type of Ash Do You Have?

There are three ash species common in the Detroit Lakes area and across Becker County:

Green Ash is the most widely planted ash in Minnesota and is extremely common on residential properties, along roads, and in shelterbelts across the lakes area. It grows 40 to 60 feet tall with a rounded crown and turns yellow in fall.

Black Ash is the most common ash in northern Minnesota woodlands and is especially prevalent in wet, low-lying areas near lakes and streams — exactly the kind of shoreline and lakeshore properties common throughout Becker County. If you have trees in a low or wet area of your property, there is a strong chance some of them are black ash.

White Ash is less common in our area but is found in southern Becker County. It tends to be larger, with a more graceful trunk, and reaches 50 to 80 feet in height.

All three species are fully susceptible to EAB. There is no ash species that is immune.

What About Mountain Ash — Is That the Same Thing?

No — and this is one of the most common points of confusion we hear from homeowners.

Mountain ash is not a true ash tree at all. It belongs to an entirely different plant family and is not susceptible to EAB. Mountain ash is typically a smaller ornamental tree, rarely exceeding 20 to 30 feet, and produces clusters of distinctive bright orange-red berries in fall. Its leaves are also compound, but they are alternate on the stem rather than opposite — and it has significantly more leaflets, typically 13 to 17.

If the branches alternate rather than grow in opposite pairs, it is not a true ash. EAB is not a concern for mountain ash.

What to Do If You Have Ash Trees

Now that you know what to look for, walk your property this week. If you have trees with opposite branching, compound leaves, and diamond-pattern bark — you have ash trees, and EAB should be on your radar.

The good news is that ash trees can be protected. Treatment is most effective on healthy trees before infestation takes hold, which is exactly why identifying your trees now — before EAB pressure intensifies in Becker County — puts you in the best possible position. We have a cerfified arborist on staff and are fully licensed and insured. 

We recently published a full guide on what EAB is, what the warning signs of infestation look like, and how our trunk injection treatment program works. If you have ash trees, that is the right next read: Emerald Ash Borer Is Moving Into Becker County — Is Your Ash Tree at Risk?

If you would rather have one of our team come out and assess your trees directly, give us a call.

(218) 849-9794

Frequently Asked Questions

Q: What is the easiest way to identify an ash tree? A: Start with the branching pattern. If the branches grow directly across from each other in matched pairs, that is opposite branching — and ash is one of the only common Minnesota trees that does this. Combine that with compound leaves carrying five to nine leaflets and you have a very reliable confirmation.

Q: I have a tree with berries — is that an ash tree? A: Almost certainly not. True ash trees produce flat, winged seeds called samaras — sometimes called helicopter seeds — not berries. If your tree has clusters of small orange or red berries, it is likely mountain ash, which is not a true ash and is not affected by EAB.

Q: Can I identify my ash tree in winter when there are no leaves? A: Yes. Opposite branching and diamond-pattern bark are visible year-round. In winter you can also look for the stout, dark brown buds that grow in opposite pairs at the tips of branches, which are characteristic of ash.

Q: If I have ash trees, do I need to do something right now? A: You should at minimum have them assessed. EAB is confirmed in surrounding counties and is considered an active and growing threat throughout the Becker County region. The earlier a treatment decision is made, the more options you have.