Pocket BotanistCheck these first
- Look for clusters of red and black bugs on the trunk.
- Check the soil moisture to see if the tree is dehydrated.
- Examine the fallen leaves for signs of disease or pests.
Likely causes
Boxelder bug infestation
Most likelyHow to tell: You will see large numbers of black and red bugs congregating on the bark and leaves. While they rarely kill the tree, heavy feeding can cause some leaf yellowing and drop.
What to do: Spray the bugs directly with a strong stream of water or an insecticidal soap. Focus on the trunk and branches where they cluster.
Severe drought
PossibleHow to tell: Leaves turn brown or yellow and fall off before the normal autumn season. The tree sheds leaves to conserve moisture.
What to do: Increase your watering frequency to every 7 days during hot weather. Apply a layer of mulch around the base to hold moisture in the soil.
Find out what's wrong with your box elder
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
Worry if the tree loses a significant portion of its canopy in mid-summer. It is normal for the tree to drop leaves as the seasons change in autumn.
Stopping it coming back
Keep the tree healthy with regular deep watering and monitor for bug clusters early in the season.
Keep your box elder healthy from here
Save your plant in Pocket Botanist and you get care reminders timed for this plant, plus a care history that shows what worked. Identification and a health check are free.
Questions people ask
- Are boxelder bugs harmful?
- They are mostly a nuisance and rarely cause significant damage to the tree itself. They are more annoying to homeowners than to the plant.
- Can I rake up the fallen leaves?
- Yes, it is good practice to remove fallen leaves to prevent fungal spores from overwintering in the soil.
More problems with Box elder
This article was generated with AI from the plant’s care profile and is general information, not horticultural advice. Read about how we build these guides.