Description:

The adults are moths with a wingspan of about 1 inch (25 mm). They are satiny white and often have a few black or brown spots on their forewings.  Mature larvae are pale yellow, black-spotted, covered with long white and black hairs and are about an inch (25 mm) in length.

Damage:

The larvae feed in colonies and produce large, dirty-white webs on the tree branches in late summer and fall.  They

Seasonal History:

The fall webworm overwinters as a pupa.  Moths appear during April and May.  The moths lay their eggs on the leaves in masses partly covered with white hairs.  Larvae hatching from these eggs construct webs over the leaves and feed inside the webs. When mature, larvae crawl to the ground and spin flimsy, hairy cocoons beneath loose debris near the surface of the soil. 

When to Control: 

Control is necessary only when the insects are numerous in a grove, but it should be done when the larvae are small.  Removing the webs by hand may be preferable if infestations are few and damage is light.