What emerald ash borer does
Emerald ash borer (EAB) is an invasive beetle first found in southeast Michigan in 2002. Its larvae tunnel under the bark and cut off the tree's flow of water and nutrients. Untreated ash trees usually die within a few years of infestation, and EAB is now found across most of the state.
Is it an ash?
- Branches and buds grow directly opposite each other.
- Leaves are compound: usually 5 to 9 leaflets on one stem.
- Mature bark has a tight, diamond-shaped ridge pattern.
Signs of emerald ash borer
- Thinning and dieback starting at the top of the crown.
- Small D-shaped exit holes (about 1/8 inch) in the bark.
- Vertical bark splits with S-shaped tunnels underneath.
- Heavy woodpecker damage, with patches of lighter bark where they've stripped it.
- Clusters of new shoots sprouting low on the trunk.
Treat or remove?
| Situation | Usual answer |
|---|---|
| Healthy or lightly affected ash you want to keep | Treatment can work. Insecticide trunk injections are typically repeated every couple of years. Ask an arborist whether the tree is a good candidate. |
| A third or more of the canopy is gone | Treatment usually isn't worth it. Plan removal. |
| Dead ash near a house, drive, road, power line or play area | Remove it, the sooner the better. |
| Dead ash out in the woods, away from anything | Can often be left, as long as it can't fall on anything or anyone. |
Why dead ash shouldn't wait
Ash killed by EAB dries out and becomes brittle much faster than most dead trees. Limbs snap without warning, and the trunk can fail at the base. That makes a dead ash more dangerous to climb, so removal often needs a lift, a crane or more careful rigging, which can raise the price the longer it stands. A dead ash near the house is worth dealing with before the next ice storm.
What happens to the wood
Ash makes good firewood, and keeping it can lower the cost of a removal. Burn it locally: moving ash firewood is how EAB spread across the state. See the cost guide for typical removal prices, or tree removal in Big Rapids.
Common questions
How much does it cost to remove a dead ash tree?
It depends on size, how close it is to buildings or lines, and how brittle it's become. Dead ash that can't be safely climbed may need a lift or crane, which adds cost. Keeping the firewood can lower the price. Request an estimate with a photo for a real number.
Is it too late to treat my ash tree?
If more than about a third of the canopy is thin or dead, treatment usually isn't worth it. Healthier ash trees can often be protected with insecticide injections repeated every couple of years.
Can I leave a dead ash tree standing?
Only if it can't hit anything or anyone when it falls. Near a house, driveway, road or power line, it should come down. Dead ash gets brittle quickly and can drop limbs or fall without warning.
Can I use ash for firewood?
Yes. It burns well. Just use it locally and don't move it to other areas, since moving firewood spreads emerald ash borer.