Pocket Botanist
Check these first
- Examine the spots for fungal growth or spores.
- Check if the spots are concentrated on lower branches.
- Look for fallen leaves around the base.
Likely causes
Anthracnose
Most likelyHow to tell: Irregular brown or black spots appear on the leaves, often following the veins. In wet springs, this can cause premature leaf drop.
What to do: Rake up and dispose of all fallen leaves to remove fungal spores. Prune out dead branches to improve air circulation through the canopy.
Leaf Spot Fungi
PossibleHow to tell: Small, circular spots with dark borders appear on the leaf surface. These are generally cosmetic and do not threaten the tree's life.
What to do: Ensure the tree is not crowded by other plants to allow for good airflow. Avoid overhead watering that keeps the foliage wet for extended periods.
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.
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When to worry
If the spots lead to massive leaf drop early in the summer, the tree may need a fungicide treatment. Most leaf spots are minor and do not require intervention.
Stopping it coming back
Keep the area under the tree clear of debris and ensure the canopy has enough space for air to move freely. Water at the base of the tree rather than sprinkling the leaves.
White Ash: spots? 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.
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Questions people ask
- Will leaf spots kill my tree?
- Usually no. Most fungal leaf spots are unsightly but do not cause long term damage to a healthy, established White Ash.
- Should I use a fungicide?
- Fungicides are rarely necessary for mature trees. They are only helpful if applied preventatively before the symptoms appear in early spring.
Guides to these causes
More problems with White Ash
This article was generated with AI on from the plant’s care profile and is general information, not horticultural advice. Read about how we build these guides.