A printable checklist for walking your own property, tree by tree, if you’d rather work through this on paper than online. Print it out and keep a copy for each ash tree you’re evaluating — check off what applies, and use the decision section at the bottom to help sort out treat, remove, or keep watching.
Part 1: Identification
Check any that apply to the tree you’re evaluating:
Opposite branching — branches grow in pairs directly across from each other on the twig (one of the few common Northeast trees that does this)
Compound leaves with 5 to 9 leaflets per leaf
Diamond-shaped bark ridges on mature trunks
Small, D-shaped exit holes in the bark, roughly 1/8 inch across
Bark splitting or flaking off in patches (“blonding”), often from woodpecker feeding underneath
Canopy dieback starting at the top and working down
Epicormic sprouting — a burst of small new shoots low on the trunk
If you checked the first two items but nothing else: this is likely a healthy or lightly-affected ash. Continue to Part 2. If you checked several of the bottom five: this tree likely has active EAB damage. A hazard assessment can confirm it and tell you how advanced it is.
Part 2: Treat, Remove, or Keep Watching?
Canopy dieback is under roughly 30% — treatment is more likely to be effective at this stage
Canopy dieback is over roughly 30-50% — treatment success rates drop considerably; removal is usually the more realistic call
The tree has real shade, landscape, or sentimental value worth an ongoing treatment commitment
The tree is positioned over a house, driveway, or anywhere people regularly walk or park — weigh risk more heavily than value here
You’re prepared to keep up a recurring treatment cycle, not just a one-time treatment
Treatment is a real option for a tree you’re prepared to keep treating on a cycle, and where you caught the damage early. Once dieback is significant, or if the tree is positioned somewhere a sudden limb failure would be dangerous, removal is the more honest recommendation regardless of sentimental value.
