How to Attract Luna Moths to Your Garden.

Delhi: The luna moth’s sole purpose is to mate, so it neither offers any specific benefits nor poses any threats to gardens. Seen primarily during spring and early summer, the moth typically produces two generations each year. Male luna moths are particularly strong fliers and may fly over relatively long distances. Female luna moths release a sex-attractant pheromone that is used to attract the male moth from a great distance. The mating usually occurs during the first couple of hours after midnight.

How would you react to seeing a Luna moth (Actias luna) for the first time, especially if you lived in an improbable setting like Maine? Spectacular and unmistakable, the moth looks as if it belongs in the tropics. Indeed, it closely resembles the Indian moon moth of Asia, the continent where most moths in the genus Actias are found.

Early American colonists were not slow to notice Luna. It was the first giant silk moth (family Saturniidae) to be mentioned in the scientific literature of North America. Detailed accounts and illustrations had been published decades before it was described by Linnaeus in 1758.

Medium-sized by Saturniid standards (its wingspan is 3-4), the Luna gains length from its delicately curved tails. Each pale-green, translucent wing bears a small eyespot; the forewings top edge is pink-to-purple. If a second generation occurs in the same year, these moths will be more yellowish-green in color, with a yellow edge. All have dark-pink legs on a stocky body that is covered with white hairs. Broad, feathery antennae are wider on males than on females.

Named after the Roman moon goddess, the Luna occurs in the eastern half of the U.S. and from southern Saskatchewan through Newfoundland. Northern populations produce one brood per year, with adults active in late spring/early summer. A mild-winter year may cause adults to eclose (emerge) from their cocoons earlier than usual, allowing time for a second brood during late summer. In the South, two to three broods are common.

When the final-instar (last molt) larva is ready to pupate, it leaves its perch in the tree and crawls or drops to the ground below. There it spins a cocoon inside a loose wrapping of leaves, which will be well-hidden in the leaf litter. Some larvae pupate in an attached leaf on the tree and then fall to the ground in autumn.

Bill Oehlke, who rears Lunas on Prince Edward Island, observes that larvae turn dark amber or burgundy-brown just before pupating if they will overwinter in the pupal stage. In areas where there are multiple broods, only the final brood darkens in color. Luna cocoons are paper thin; the active pupa can be seen if held to the light. Cocoons of individuals that will enclose the same summer are usually nearly white in color; those that will overwinter are tan or brown.

The adult moth normally closes from its cocoon in mid-morning. Says Oehlke, “The moth makes quite a racket as it heaves against one end of the cocoon, tearing at the silk with hornlike projections near the base of the forewing. A secretion called cocoonase helps to break down the sericin binding the silk.”