Fall Webworms Bring Early Halloween Look to Fredericksburg

The fall webworm has brought an early Halloween look to parts of Fredericksburg. The caterpillar's feeding strategy involves creating wispy webs on pecan trees, which can be mistaken for giant spider nests.

Fall webworms are typically yellow or green with white and black hairs, growing up to an inch long. Adult moths are white with occasional speckling on their wings and have a fuzzy thorax with toothed antennae.

The fall webworm has two to four generations per year in Gillespie County, mainly affecting pecan trees but also mulberries, willows, and boxelders. A female moth lays her eggs near the webby nest she came from, producing between 400 and 1,000 eggs in one batch.

If you've noticed an increase in webworms as summer progressed, it's because each generation only takes about 50 days to mature. The Gillespie County Extension Office notes that areas with higher concentrations of pecan trees tend to have more issues due to the increased number of targets and difficulty spraying for fall webworms.