Will my tree die if it has webworms?

Usually not. While the webs look alarming and the defoliation can weaken a tree, most healthy trees will recover and push out new leaves once the infestation is gone.

Should I burn the webs out of the tree?

No. Burning the webs is dangerous and often causes more damage to the tree bark and branches than the caterpillars themselves.

Webworms

Symptoms by part

Leaves

You will see dense, white, silken webs enclosing clusters of leaves at the ends of branches, often containing small caterpillars and their dark droppings.

Causes

The presence of adult moths laying eggs on the undersides of leaves during the warm growing season.
A lack of natural predators like birds or parasitic wasps in the immediate area.
Warm, dry weather conditions that favor rapid larval development.

Could be confused with

Tent Caterpillars · Tent caterpillars build their nests in the crotches of branches rather than at the tips of branches like webworms.
Bagworms · Bagworms create individual, cone shaped cases made of plant debris that hang from twigs, whereas webworms create communal, messy silken webs.

Treatment

Use a long pole or a sturdy stick to physically break open the silken nests, which exposes the larvae to birds and other predators.
Prune out the infested branch tips containing the nests using clean, sharp shears and dispose of them in a sealed bag.
Apply Bacillus thuringiensis to the foliage surrounding the nest area to target the larvae as they feed, follow the label.

Without chemicals

Pruning away the webbed branch tips early in the season.
Using a high pressure water spray to blast the webs apart and dislodge the larvae.
Encouraging local bird populations to visit the garden.

Chemical options

Bacillus thuringiensis, spray directly onto the foliage where larvae are feeding, follow the label.

Preventing it

Keep trees and shrubs healthy through proper watering and mulching to help them withstand minor defoliation.
Remove any visible egg masses from the undersides of leaves during the early stages of the warm growing season.
Avoid using broad spectrum insecticides that kill off the beneficial insects that naturally hunt webworms.

Season

The warm growing season.

Spread risk

Moderate

Severity

Moderate

When to act

Act as soon as you notice the small, developing webs to prevent them from growing large and causing significant damage. If the webs are located too high in a tree to reach safely, contact a tree surgeon to handle the removal.

Think it's Webworms?

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Questions people ask

Will my tree die if it has webworms?: Usually not. While the webs look alarming and the defoliation can weaken a tree, most healthy trees will recover and push out new leaves once the infestation is gone.
Should I burn the webs out of the tree?: No. Burning the webs is dangerous and often causes more damage to the tree bark and branches than the caterpillars themselves.

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This guide was generated with AI and is general information, not horticultural advice. Read about how we build these guides.