NC State Extension Publications

General Information

There are more than 1,400 kinds of moths and butterflies in North Carolina. Some of these lay eggs from which hatch destructive caterpillars that feed on our trees and shrubs.

The moths and butterflies (adults) cannot do any damage to plants themselves. The following caterpillars are commonly reported from ornamental plants. Not all occur in high numbers to be considered pests. Learn more about the species of your interest before applying pesticides.

Sawflies in the larval stage look very much like moth caterpillars. They may cause severe defoliation. Sawflies belong in the group of insects which includes ants, bees, and wasps.

Figure 1. Giant swallowtail.

Figure 1. Giant swallowtail.

Figure 2. Greenstriped mapleworm.

Figure 2. Greenstriped mapleworm.

Figure 3. Pinkstriped oakworm.

Figure 3. Pinkstriped oakworm.

Figure 4. Walnut caterpillar.

Figure 4. Walnut caterpillar.

Figure 5. Dusky birch sawfly caterpillar feeding on birch.

Figure 5. Dusky birch sawfly caterpillar feeding on birch.

Control

The single attack of a leaf-feeding insect will seldom kill a healthy tree or shrub. Repeated defoliations, however, may weaken and make them susceptible to destruction by other insects, diseases, severe cold weather, drought, etc. Most of those listed above are not a serious threat.

Try to identify the specific insect before taking control measures. Your local Cooperative Extension Center can help. Further information about some of the more serious caterpillar pests is contained in other specific insect pest notes.

The following pesticides are labeled for "caterpillars." Other pesticides may be labeled for certain types of caterpillars such as armyworms, bagworms, cankerworms, webworms. Some pesticides are labeled for specific caterpillars such as yellownecked caterpillars or eastern tent caterpillars.

A complete list of all such pesticides and all of their target pests is too long for this insect note. The Southeastern US Pest Control Guide for Nursery Crops and Landscape Plantings has a more complete list of pesticides and target pests. Bacterial insecticides such as B.t. are useful when caterpillars are small.

Other Resources

For assistance with a specific problem, contact your local Cooperative Extension center.

Authors

Professor and Extension Specialist
Entomology & Plant Pathology
Retired Extension Specialist (Home Ornamentals/Turf)
Entomology & Plant Pathology

Publication date: July 1, 2009

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