Fall Webworm Photos

Shaun Bennett MAF NPPRL

Newly hatched caterpillars spin a loose, silken web over the foliage they feed on. As the caterpillars grow, they enlarge the web to enclose more leaves. These webs are usually formed at the end of branches. It is easy to mistake a fall webworm web for a spider's nest which is smaller and tighter and will have small spiders in it instead of caterpillars.

Egg Mass

 

Lacy L. Hyche, Auburn University

Several hundred eggs (up to 500) are laid on the underside of a leaf in a hair covered mass. These small, yellow or light green eggs turn grey before they hatch.

Larvae (Caterpillars)

 

Lacy L. Hyche, Auburn University

Up to 3 cm long, these pale yellow to green caterpillars are covered with long white/grey silken hairs that arise in tufts from black or yellow bases. They have a black stripe down their back and yellow racing stripes down each side. They have black or reddish heads. They are likely to be found in or nearby a silken web.

Pupae (Cocoon)

 

Shaun Bennett MAF NPPRL

Develop inside grey cocoons made of silk, frass (insect poo) and debris. They are usually found on the ground in soil and leaf litter beneath or near the host tree. They can also be found in old nest remains or under loose bark.

Moths

 

Lacy L. Hyche, Auburn University

With a wing span of about 2.5-4 cm, the moths are snowy white. The bases of their front legs are orange or bright yellow.

Both images Shaun Bennett MAF NPPRL

Caterpillars spin a silken web around the foliage of a tree and feed on the enclosed leaves.

Page last updated: 30 April 2008