Your ash tree is dead. Here is what happens next

How to tell if it is ash, and whether it is gone

Ash has a distinctive diamond-pattern bark on a mature trunk, opposite branching (twigs come off in matching pairs, which is unusual), and compound leaves made of five to eleven leaflets on a single stem. If your tree has all three, it is almost certainly ash.

The signs it has been hit are consistent and easy to read once you know them. Thinning that starts at the very top of the crown and works down. Shoots sprouting from the trunk and the base, which is the tree's last attempt to make leaves somewhere the borer has not reached. D-shaped exit holes about three millimetres across in the bark. Serpentine tunnels underneath if a patch of bark comes away. And woodpecker damage: heavy flaking of the outer bark, sometimes called blonding, where birds have been working the trunk over for larvae.

The last of those is the one people misread. Woodpeckers stripping your ash is not the problem, it is the diagnosis. They are there because the tree is full of larvae.

Why a dead ash is a different job from any other dead tree

Ash goes brittle fast, and it does it from the top down. Within roughly two seasons of dying, the upper limbs stop bending and start snapping. Within three or four, the wood in the crown can fail under a climber's weight with no warning and no sound, and the bark begins shedding in sheets.

That changes the method completely. A recently dead ash can often still be climbed and dismantled conventionally. One that has been standing dead for several years cannot be climbed safely at all, so it has to come apart from a machine, a lift, or be felled whole if there is genuinely somewhere to put it. Fewer options means a harder job.

This is the part worth understanding: a dead ash gets more difficult and more dangerous every single year it stands. Most tree problems can wait a season without changing. This one actively degrades. If you are weighing up whether to deal with it now or next year, the tree is not going to make the decision easier for you.

How urgent is yours, honestly

It depends almost entirely on what is underneath it. A dead ash at the back of five acres, standing over nothing, is not an emergency and arguably not a problem at all. Standing dead trees are genuinely good wildlife habitat, and if it can fall in any direction without hitting anything, leaving it is a legitimate choice.

A dead ash over a house, a driveway where cars park, a garden anyone sits in, a fence line, a road, a play structure or a hydro service drop is a different matter, and the honest answer there is that it should have come down already.

The in-between case is a dead ash near a boundary. Falling limbs do not respect property lines, and a limb from your tree that lands on a neighbour's roof is a conversation you would rather not be having. Worth dealing with before the wind decides.

What about treating it instead

Injection treatments for emerald ash borer do exist and they do work, but only as prevention on a tree that is still healthy. The product moves through living tissue, so it needs a functioning vascular system to distribute it. Once a significant share of the crown is gone, there is not enough live tree left to carry it, and treating at that stage is spending money on a tree that is going to come down anyway.

Treatment is also not one-and-done. It has to be repeated on a cycle, indefinitely, for as long as you want the tree. That can be entirely worth it for a specimen tree you genuinely value, in a spot that would be much poorer without it. It is not worth it for an average boulevard ash.

If you have an ash that still looks good and you want to keep it, that is a conversation worth having now rather than in two years. If the crown is already thin at the top, the decision has effectively been made for you.

What removal involves, and what comes after

A dead ash has to be planned around brittleness rather than around size. That usually means taking it apart from the grapplesaw rather than putting a climber into it, working in smaller pieces than the wood looks like it should need, and not assuming any union will hold.

The wood itself is worth knowing about. Ash is excellent firewood, genuinely one of the best, and it burns well at a lower moisture content than most hardwoods. If you burn, say so and it can be left cut to length rather than chipped. What you should not do is move ash firewood any distance, because that is exactly how the borer spread across Ontario in the first place. Burn it where it fell.

Then there is the stump. Ash does not sucker aggressively the way locust or Manitoba maple does, so a cut stump will not usually fight you. But if the ground needs to be mowable, plantable or buildable, it needs grinding out. Worth deciding at the same time so it can be handled in one visit.

If you have more than one dead ash, and a lot of properties around Courtice, Whitby and Oshawa do, mention all of them when you call. Planning them together is far less disruptive than the same crew coming back three times.