Ailanthus Webworm Moth

Natural Habitat

Found in areas where its host plant, the Ailanthus altissima (Tree of Heaven), is present. This includes urban and suburban areas, disturbed sites, roadsides, and woodlands.

Diet & Feeding

The caterpillars feed exclusively on the leaves of the Tree of Heaven (Ailanthus altissima) and sometimes other related plants in the Simaroubaceae family. Adult moths feed on nectar from various flowers.

Behavior Patterns

The Ailanthus Webworm Moth is active during the day and is often seen flying around its host tree. The caterpillars construct silken webs on the tree branches, within which they feed and develop. They are gregarious within these webs. There can be multiple generations per year, especially in warmer climates.

Risks & Benefits

Potential risks are minimal to humans, as they are not known to bite or sting. The primary risk is to the Tree of Heaven (Ailanthus altissima), an invasive species in North America, which the caterpillars defoliate. This can be considered a benefit as the moth acts as a natural biological control agent against this invasive tree, helping to reduce its spread and impact on native ecosystems.

Identified on: 9/26/2025