Webworm, common name applied to the caterpillars of various widely distributed moths for their habit of spinning large communal webs. The fall webworm reaches a length of 1.9 cm (0.75 in). Members of this species spin a common web, enclosing several leaves or whole branches of trees; after devouring the leaves on one tree, they move on to another. The fall webworm is usually dark green in color and is covered with rough, long hairs. The garden webworm feeds on garden vegetables by drawing the leaves into its web. It is yellow, spotted with black, and averages 2.5 cm (1 in) in length. The corn root webworm spins a web around the stalks and roots of various grasses. It is dark brown above and lighter below and feeds only at night. During the day, corn root webworms retire to a tube of cut grass and silk below the surface of the ground. Methods of protecting crops against webworms include the burning of webs and plowing early in the fall.
Scientific classification: Webworms belong to the order Lepidoptera. The fall webworm belongs to the family Arctiidae. It is classified as Hyphantria cunea. The garden webworm and corn root webworm belong to the family Pyralidae. The garden webworm is classified as Achyra rantalis and the corn root webworm as Crambus caliginosellus.