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Zeuzera pyrina

Leopard moth caterpillar. Photo: Jean-Paul Grandjean, Office National des Forêts, Bugwood.
Scientific Name: 
Zeuzera pyrina
Common Name: 
Leopard Moth
Growing Degree Days (GDD's): 
None available at this time.
Host Plant(s) Common Name (Scientific Name): 
Apple (Malus spp.)
Ash (Fraxinus spp.)
Beech (Fagus spp.)
Birch (Betula spp.)
Blackcurrant (Ribes spp.)
Cherry (Prunus spp.)
Chestnut (Castanea spp.)
Cotoneaster (Cotoneaster spp.)
Elm (Ulmus spp.)
Hawthorn (Crataegus spp.)
Lilac (Syringa spp.)
Maple (Acer spp.)
Mountain ash (Sorbus spp.)
Oak (Quercus spp.)
Pear (Pyrus spp.)
Plum (Prunus spp.)
Poplar (Populus spp.)
Quince (Chaenomeles spp.)
Rhododendron (Rhododendron spp.)
Walnut (Juglans spp.)
Willow (Salix spp.)
Insect Description: 

Zeuzera pyrina was introduced from Europe and North Africa accidentally into the United States and first reported in New Jersey in 1887. It has since increased its range westward and southward. Adult leopard moths are white with numerous black spots on the thorax and wings, and can be up to 1.5 inches long. They can be found approximately from May to September during the growing season. (This varies upon geographic location. In New Hampshire, adults may be most common from early-July through mid-August.) Adults are described as heavy-bodied, weak flyers. Male moths are noted to be strongly attracted to lights. Eggs (light yellow to bright salmon/pink in color) are laid in masses or clusters in bark crevices and females are capable of laying up to 800 eggs in a single season. Larvae bore in through the bark and feed, eventually in the heartwood. Caterpillars may also be referred to as "carpenterworms" because this life stage is found developing in the wood of host plants. Larvae are also capable of relocating to new branches if the one it selects is too small for its full development. Mature caterpillars can be up to 2 inches long, pale yellow in color, with black heads and black dots on the body. Larvae are commonly found in branches as well as the trunk. The life cycle of the leopard moth typically takes two years to complete, with pupation occuring in a larval gallery.

Damage to Host: 

Smaller diameter trees and branches are often most harshly impacted by this insect. In these scenarios, dieback can occur. Frass (large, coarse pellets) may be seen falling from cracks in the bark. Similar species also referred to as carpenterworms (ex. Prionoxystus robiniae) may cause similar damage and symptoms on overlapping hosts. Exit holes from adult moths leaving the host plant can sometimes be found in limbs, with the old pupal case remaining in the hole. Over 125 species of deciduous trees have been recorded as hosts of the leopard moth. Even though this insect is widespread, it historically has not been considered to be an important pest in New England because populations generally remain low. In other countries, it is a significant pest of olives, apples, and pears and there is concern about range shifts of the leopard moth due to climate change (Fekrat and Farashi, 2022). 


Look for branch dieback and frass sticking out of deep bark cracks or gallery openings. Check stressed trees first. 

Cultural Management: 

Promoting tree vigor with appropriate practices for the host plant, especially adequate watering, can help prevent leopard moth attacks. Prevent mechanical damage to trees, as this may be attractive to the leopard moth and other woodboring insects.

Natural Enemies & Biological Control: 

Woodpeckers and certain other bird species are the main predators of the leopard moth. Additional natural enemies of this insect have been noted, including but not limited to: Copidosoma truncatellum (egg parasitoid), Diadegma terebrans (ichneumonid wasp parasitoid), and other parasitoid wasps depending upon geographic location (CABI; Invasive Species Compendium). Natural enemies also include certain species of nematode, such as Steinernema carpocapsae and Steinernema feltiae (CABI; Invasive Species Compendium).

Chemical Management: 

Abamectin (NL)

Acephate (NL)

Azadirachtin (NL)

Bifenthrin (NL)

Chlorantraniliprole (NL)

Chlorpyrifos (N)

Cyantraniliprole (NL)

Emamectin benzoate (L)

Indoxacarb (L)

Permethrin (L)

Spinetoram+sulfoxaflor (N)

Spinosad (NL)

Tebufenozide (NL)


Active ingredients that may be injected include: Abamectin (injection), acephate (injection), and chlorantraniliprole (soil drench).

When used in a nursery setting, chlorpyrifos is for quarantine use only.

Make insecticide applications after bloom to protect pollinators. Applications at times of the day and temperatures when pollinators are less likely to be active can also reduce the risk of impacting their populations.

Note: Beginning July 1, 2022, neonicotinoid insecticides are classified as state restricted use for use on tree and shrub insect pests in Massachusetts. For more information, visit the MA Department of Agricultural Resources Pesticide Program.

Read and follow all label instructions for safety and proper use. If this guide contradicts language on the label, follow the most up-to-date instructions on the product label. Always confirm that the site you wish to treat and the pest you wish to manage are on the label before using any pesticide. Read the full disclaimer. Active ingredients labeled "L" indicate some products containing the active ingredient are labeled for landscape uses on trees or shrubs. Active ingredients labeled "N" indicate some products containing the active ingredient are labeled for use in nurseries. Always confirm allowable uses on product labels. This active ingredient list is based on what was registered for use in Massachusetts at the time of publication. This information changes rapidly and may not be up to date. If you are viewing this information from another state, check with your local Extension Service and State Pesticide Program for local uses and regulations. Active ingredient lists were last updated: January 2024. To check current product registrations in Massachusetts, please visit: .