Luna moths are one of the important insect pests of walnuts

What are luna moths?

The luna moths (Actias luna) are one of the largest and most beautiful moths in North America, strong fliers, active during nights, attracted to lights and belong to an insect order Lepidoptera. These moths have light green colored wings with yellow stripes, a false eyespot on each forewing and hindwing with long curving tails (Photo 1). The life cycle of luna moths contain four developing stages including eggs, caterpillars, pupae and adults.

Female moths generally lay whitish- brown colored eggs on both sides of the leaves. These eggs hatch in a week into small green colored caterpillars that develop through five stages. Mature larvae pupate in the silken cocoons, which are wrapped in the leaves. Under favourable conditions, luna moths can complete their life cycle within a month.

Photo 1. Luna Moth

Damage caused by luna moths

Only caterpillars of luna moth cause feeding damage to the leaves of a variety of trees including white birch (Betula papyrifera), persimmon (Diospyros virginiana), hickory nuts (Carya spp.) and walnuts (Juglans spp.) but damage caused by them is not considered significant and therefore, do not have to worry about controlling them.

Natural enemies

Although there is no need to control luna moths, several natural enemies like predators and parasitoids may be helping to keep their populations in check.