Common Moths in Pennsylvania That Resemble the Box Tree Moth

Box Tree Moth

Cydalima perspectalis

The box tree moth (Cydalima perspectalis Walker) (Lepidoptera: Crambidae) is an invasive species native to eastern Asia. Its caterpillars are voracious feeders, capable of completely defoliating their host plants. Once the leaves are consumed, they begin feeding on the bark, which can ultimately kill the plant. The box tree moth's most common host in the United States is boxwood. Although boxwood is not native to the U.S., it is widely used as an ornamental plant in many landscapes.

The box tree moth was first detected in the U.S. in 2021 in New York. Since then, it has been confirmed in Michigan, Ohio, Massachusetts, Delaware, and most recently Pennsylvania. In September 2024, the presence of this moth was confirmed in two cemeteries in Erie County, Pennsylvania. Due to its status as a federally regulated pest, Erie County is now under quarantine. Boxwood plants cannot be moved out of the county unless they have been treated, and the seller holds a compliance agreement with the Pennsylvania Department of Agriculture (PDA). This compliance agreement will require nurseries to conduct scouting, trapping, treatments, and training and maintain detailed records. Nurseries should contact the PDA to enter into a compliance agreement.

For the latest information on box tree moth identification and its spread, please refer to Dr. Michael Skvarla's article, Box Tree Moth. For management options, consult the Box Tree Moth: Management Guide.

While the known distribution of the box tree moth is currently limited to Erie County, if you are in other counties in Pennsylvania and believe you have found a box tree moth, please contact your local Penn State Extension office close to you or Contact the Pennsylvania Department of Agriculture at badbug@pa.gov or 866-253-7189.

Correct identification is crucial in preventing the spread of invasive species. Below are two moths found in Pennsylvania that resemble the box tree moth.

Melonworm Moth

Diaphania hyalinata Linnaeus

The melonworm moth is commonly found in the southeastern United States and may occasionally migrate to Pennsylvania in the fall. Although it bears some resemblance to the box tree moth, the melonworm moth has distinct characteristics:

• Adults have white wings bordered by a dark brown or black edge.
• The body is mostly white with some dark markings.
• Caterpillars are slender, light green, and have long white stripes running along their bodies.

Despite these similarities in appearance, the melonworm moth does not feed on boxwood. Its primary hosts are plants from the cucurbit family. The larvae feed on foliage, causing defoliation, and may also damage fruits.

Pickleworm Moth

Diaphania nitidalis Stoll

The pickleworm moth is a tropical insect that typically survives the winter only in southern Florida and possibly southern Texas. In North Carolina and South Carolina, crop damage caused by pickleworms usually doesn't occur until late in the season, around August or September. In some years, the moths can be found as far north as Michigan and Connecticut. While the pickleworm moth is more distinct than the melonworm moth, it can sometimes be mistakenly identified as the box tree moth.

• Adults have translucent, golden-brown wings with purple borders.
• The body is golden or brown.
• Caterpillars are pale yellow to green with small spots along their body length, becoming more orange as they mature.

They feed primarily on the fruits of cucurbit plants, such as cucumbers, squash, pumpkins, and melons.