The Luna Moth (Actias luna) is a striking member of the giant silk moth family, recognizable by its pale, often lime-green coloration and large size. With a wingspan typically ranging from three to four-and-a-half inches, it is one of the largest and most spectacular moths found across North America. Each of its four wings features a prominent eyespot, and the hindwings trail into elegant, sweeping tails. This creature is largely nocturnal, meaning it is most active at night.
The Critical Role of Host Plants
The life cycle of the Luna Moth is entirely dependent on specific vegetation for the survival of its young. Adult moths live for only about a week and possess vestigial, non-functional mouthparts, meaning they do not feed. Their brief existence is dedicated solely to reproduction, relying on fat reserves accumulated during the larval stage. A female moth must locate a suitable plant upon which to lay her eggs. These plants are known as host plants, and the female must choose carefully, as the larvae cannot easily switch to a different species later on.
Primary Host Plants for Larvae
The preferred host plants for Luna Moth larvae belong to a few key tree families across its wide range. Sweetgum (Liquidambar styraciflua) is a primary host, favored throughout the moth’s distribution, especially in southern and central regions. Its foliage provides a reliable and abundant food source for the growing caterpillars. Various species of Hickory (Carya species) are also highly preferred, including pecan.
Trees within the Walnut family (Juglans species), including Black Walnut and Butternut, are consistently chosen by egg-laying females. The prevalence of these species in deciduous woodlands throughout the eastern United States makes them readily available choices. To attract Luna Moths, planting these native tree species is recommended. Maintaining a pesticide-free environment around these host trees is important, since the caterpillars are highly sensitive to chemical treatments.
Regional and Secondary Host Plants
The Luna Moth exhibits adaptability, and its host plant selection is strongly influenced by geography, leading to a variety of regional and secondary food sources. In the northern parts of the moth’s range, stretching into Canada, White Birch (Betula papyrifera) often takes the place of southern favorites as the most frequently used host tree.
Conversely, in the Deep South, American Persimmon (Diospyros virginiana) is a significant host plant, heavily used by the multiple generations of moths that emerge in warmer climates each year. This diversity in host plant selection ensures the moth’s survival across its extensive territory, from Florida to Quebec.
Other secondary host plants include several species of Sumac (Rhus species) and Willow (Salix species). These trees are utilized when primary choices are less available or as a supplementary food source. The female moth’s choice of a host plant is critical, as it determines the entire food supply for the next generation of larvae.