The Luna Moth (Actias luna) is one of North America’s largest and most easily recognized silk moths. This species features a delicate, pale green coloration and a wingspan that typically ranges from three to four and a half inches. Its large size and distinctive, long, sweeping tails on the hindwings make it easily identifiable. It is sometimes referred to as the American Moon Moth.
Geographic Distribution
The range of the Luna Moth primarily covers the eastern half of North America. It is found from southern Canada (Nova Scotia westward to Saskatchewan) south through the United States, reaching the Gulf Coast states, including Florida and eastern Texas. The western boundary is generally defined by the Great Plains, meaning sightings are concentrated east of this line.
The moth is present in nearly every eastern state, thriving in the broad stretch of forested land that characterizes this region. While the moth is widespread, its density can vary significantly based on the local environment.
Preferred Habitats and Host Trees
The species exhibits a strong preference for deciduous woodlands and temperate forests, which provide the necessary resources for its life cycle. The presence of specific larval host plants is a determining factor for where populations can establish themselves.
Luna Moth caterpillars are herbivores that feed on the foliage of numerous deciduous trees, including Sweetgum, Walnut, Hickory, and Birch. In northern parts of the range, White Birch often serves as a primary host, while Southern populations tend to rely more heavily on Sweetgum and Persimmon.
The adult moths are often spotted near forest edges or in wooded suburban areas where these host trees are abundant. Searching near these specific tree types increases the chances of a sighting, as the female lays her eggs on the leaves of these plants.
Timing the Search
Observing an adult Luna Moth requires precise timing. The adult moth is strictly nocturnal, flying only at night, and its entire adult lifespan lasts only about one week. This short window exists because the adult lacks functional mouthparts and survives solely on energy reserves stored during its caterpillar stage.
The flight season, or the time when adults emerge, varies significantly with latitude. In far northern areas, such as Canada and the northern U.S., the moth is typically univoltine, producing one generation per year from late May through June. Farther south, in the Ohio Valley and mid-Atlantic states, the species is bivoltine, completing two generations between late spring and late summer. In the deep South, the warmer climate allows for up to three broods, with the first adults appearing as early as March.
Identifying and Observing
Identifying a Luna Moth is straightforward due to its unmistakable physical characteristics. The adult moth features a bright lime-green color that often fades to a more yellowish hue in later-season broods. Each wing displays a prominent, transparent eyespot, and the long, graceful tails extend from the hindwings. The male can be distinguished from the female by his larger, more heavily feathered antennae, which he uses to detect the female’s pheromones over long distances.
The most practical way to observe these nocturnal insects is by using artificial light sources near wooded areas. Luna Moths are strongly attracted to white or ultraviolet (UV) light, which is more effective than standard yellow bug lights. Setting up a white sheet illuminated by a UV or bright white light can draw them in after dark. Moths are also frequently found resting on screens, porches, or the walls of buildings near exterior lights early in the morning.