Can I save my tree from the Emerald Ash Borer?

If caught early, professional systemic treatments can protect the tree. Once the tree shows significant canopy dieback, it is usually too late.

Do I need to spray my whole tree?

Only spray if you identify a specific pest like the ash plant bug. Never spray the entire tree for the borer, as that requires specialized trunk injections.

Why are there pests on my White Ash tree? Causes and fixes

Check these first

Inspect the trunk for small D shaped holes.
Look for woodpecker activity on the bark.
Check the undersides of leaves for small insects.

Likely causes

Emerald Ash Borer
Most likely
How to tell: Look for D shaped exit holes in the bark and thinning leaves at the top of the canopy. You might also see woodpecker damage as they hunt for larvae.
What to do: Contact a certified arborist immediately to discuss systemic insecticide treatments. If the infestation is advanced, removal is often the only safe option to prevent spread.
Ash Plant Bug
Possible
How to tell: These small bugs cause yellow or white stippling on the leaves. You will see the insects on the undersides of the foliage.
What to do: Use a gentle insecticidal soap spray on the leaves during the early morning. Repeat the application every 7 to 10 days if the bugs persist.

Pests on other plants

Find out what's wrong with your white ash

The list above covers the usual causes. Pocket Botanist looks at a photo of your actual plant and tells you the likely cause, how serious it is, and what to try first. Identification and a health check are free.

When to worry

If you find D shaped holes, it is a serious emergency that requires professional help. Minor leaf bugs are usually just a cosmetic nuisance.

Stopping it coming back

Keep your tree healthy with regular deep watering and mulch to reduce stress. Consult a local arborist about preventative trunk injections if the borer is in your area.

White Ash: pests? Check yours with a photo

Every plant is a little different. Take a photo of your white ash and Pocket Botanist tells you which cause is most likely, how serious it is, and what to try first. A few checks a day are free. Save the plant and you get care reminders timed for it.

Get the app · Or check it from a photo now, free

Questions people ask

Can I save my tree from the Emerald Ash Borer?: If caught early, professional systemic treatments can protect the tree. Once the tree shows significant canopy dieback, it is usually too late.
Do I need to spray my whole tree?: Only spray if you identify a specific pest like the ash plant bug. Never spray the entire tree for the borer, as that requires specialized trunk injections.

Why are there pests on my White Ash tree?