Can I use chemical pesticides?

Avoid harsh chemicals, as they often kill the beneficial insects that eat the pests. Stick to soaps or oils first.

Do these bugs kill the tree?

Usually no, but they can weaken it over time. Treat them early to prevent the tree from becoming stressed.

Are there bugs on my American hornbeam? Causes and fixes

Check these first

Inspect the undersides of the leaves with a magnifying glass.
Look for sticky residue on the leaves or the ground below.
Check for fine webbing between the branches.

Likely causes

Aphids
Most likely
How to tell: You might see tiny green or black insects on the undersides of leaves or sticky honeydew on the foliage. The leaves may look slightly curled or distorted.
What to do: Spray the leaves with a strong stream of water to dislodge the aphids. If the infestation is heavy, apply insecticidal soap according to the label instructions.
Mites
Possible
How to tell: Leaves look stippled or pale, and you might see fine webbing between the leaf veins. The tree may look generally lackluster and dull.
What to do: Increase humidity around the tree if possible, as mites dislike moisture. Use a horticultural oil spray to manage the population if the damage is widespread.

Pests on other plants

Find out what's wrong with your american hornbeam

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 the tree shows significant yellowing or branch dieback, the pest population is likely too high to ignore. It is normal to see a few stray bugs on any outdoor tree.

Stopping it coming back

Keep the tree well watered and healthy, as stressed trees are more attractive to pests. Encourage beneficial insects like ladybugs to visit your garden.

American hornbeam: pests? Check yours with a photo

Every plant is a little different. Take a photo of your american hornbeam 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 use chemical pesticides?: Avoid harsh chemicals, as they often kill the beneficial insects that eat the pests. Stick to soaps or oils first.
Do these bugs kill the tree?: Usually no, but they can weaken it over time. Treat them early to prevent the tree from becoming stressed.

Guides to these causes

Aphids

Are there bugs on my American hornbeam?