There are over 1400 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.
Bagworm ‑ mostly evergreen
Birch skeletonizer ‑ birch
Cankerworm ‑ elm, maple, oak, etc.
Cecropia moth ‑ many trees
Eastern tent caterpillar ‑ cherry, apple
Fall webworm ‑ pecan, elm, etc.
Forest tent caterpillar ‑ maple, oak, poplar
Greenstriped mapleworm ‑ maple, oak, etc.
Hemlock looper ‑ hemlock
Hickory horned devil ‑ hickory, walnut
Imperial moth ‑ many trees
Io moth ‑ various trees and shrubs
Juniper webworm ‑junipers
Luna moth ‑ many forest and shade trees
Pinkstriped oakworm ‑ oak
Polyphemus moth ‑ many trees
Poplar tentmaker ‑ poplar, willow
Promethea moth ‑ many trees
Redhumped caterpillar ‑ cherry, dogwood
Redhumped oakworm ‑ oak, elm, etc.
Saddled prominent ‑ maple, beech, etc.
Regal moth (hickory horned devil)
Spiny oakworm ‑ oak
Stinging caterpillars ‑ oak, many others
Uglynest caterpillar ‑ cherry, etc.
Walnut caterpillar ‑ pecan, walnut, etc.
Yellownecked caterpillar ‑ hickory, oak
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.
Dusky birch sawfly ‑ birch
Elm sawfly ‑ elm
Pin oak sawfly ‑ oak
Redheaded pine sawfly
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 Office can help.
Bacillus thuringiensis (B.t.) or acephate (Orthene) are labeled for caterpillars control. B.t. Will be most effective on caterpillars when they are small and less effective as they grow larger. Other insecticides may be labeled for certain types of caterpillars. As with any pesticide application, be sure the plant you are applying the chemical to is listed on the label.