Pocket BotanistCheck these first
- Examine the trunk and branches for sunken bark.
- Check the soil moisture level 6 inches deep.
- Look for signs of wilting before the leaves drop.
Likely causes
Canker disease
Most likelyHow to tell: You will see sunken, discolored patches on the bark of branches or the trunk. Leaves above these areas will wilt and drop prematurely.
What to do: Prune out infected branches about 6 inches below the visible canker. Sterilize your pruning shears with alcohol between every cut to avoid spreading the fungus.
Drought stress
PossibleHow to tell: Leaves turn yellow or brown at the edges before falling off. The soil around the base feels dry and cracked.
What to do: Water the tree deeply every 7 to 14 days during dry spells. Ensure the water reaches the root zone by letting the hose run slowly for an hour.
Find out what's wrong with your eastern cottonwood
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.
Scan with your phone's camera to get the app
Or go to pocketbotanist.app/get on your phone
When to worry
Worry if you see large sunken areas on the main trunk, as this can be fatal. Normal leaf drop is expected in the autumn as the tree prepares for winter.
Stopping it coming back
Avoid wounding the tree with lawn mowers or trimmers, as these wounds are entry points for canker fungi. Maintain consistent moisture during the growing season.
Eastern Cottonwood: leaf drop? Check yours with a photo
Every plant is a little different. Take a photo of your eastern cottonwood 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.
Scan with your phone's camera to get the app
Or go to pocketbotanist.app/get on your phone
Get the app · Or check it from a photo now, free
Questions people ask
- Is it normal for my tree to drop leaves in July?
- No, that is a sign of stress. It usually means the tree is either too dry or fighting a disease.
- How do I know if a branch has a canker?
- Look for bark that looks sunken, cracked, or has a different color than the rest of the branch. It often looks like a wound that will not heal.
Guides to these causes
More problems with Eastern Cottonwood
Back to the Eastern Cottonwood guide
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.