Will the honeydew hurt my tree?

The honeydew itself is just a byproduct, but it can lead to sooty mold. The real issue is the aphids draining the tree's energy.

Can I use systemic pesticides?

It is best to avoid them on large trees like the American linden. They can harm beneficial pollinators that visit the flowers.

American linden: pests, causes and fixes

Check these first

Inspect the undersides of leaves for clusters of small insects.
Touch the leaves to see if they feel sticky.
Look for ants, which often farm aphids for their honeydew.

Likely causes

Aphid infestation
Most likely
How to tell: You will see sticky residue on leaves and branches, often accompanied by tiny soft bodied insects on the undersides of leaves.
What to do: Spray the foliage with a strong stream of water from your garden hose to dislodge the aphids. If the infestation is heavy, apply insecticidal soap directly to the affected areas every 5 to 7 days until they are gone.
Sooty mold growth
Possible
How to tell: A black, powdery coating appears on the leaves where the sticky honeydew has accumulated.
What to do: Wash the leaves with a gentle soap solution to remove the mold. Once you eliminate the aphids, the mold will stop spreading and eventually weather away.

Pests on other plants

Find out what's wrong with your american linden

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

A few aphids are normal, but if the tree is covered in sticky honeydew or the leaves start curling, you should take action. It is rarely fatal, but it can make a mess of your patio or sidewalk.

Stopping it coming back

Encourage natural predators like ladybugs and lacewings to visit your garden by planting diverse flowers nearby. Avoid heavy nitrogen fertilizers that encourage soft, succulent growth which aphids love.

American linden: pests? Check yours with a photo

Every plant is a little different. Take a photo of your american linden 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

Will the honeydew hurt my tree?: The honeydew itself is just a byproduct, but it can lead to sooty mold. The real issue is the aphids draining the tree's energy.
Can I use systemic pesticides?: It is best to avoid them on large trees like the American linden. They can harm beneficial pollinators that visit the flowers.

Guides to these causes

Aphids

Why are there sticky drops on my American linden leaves?