Meet your mostly harmless neighbors
Moths can cause problems, but many are pretty pollinators
My mother called moths pests because they chewed up clothes in closets and infested food pantries.
I later learned that pesky clothes moths in the Tineidae family lay eggs on clothes, where larvae hatch to feed on animal fibers such as wool and felt. Pantry moths are in the Pyralidae family and lay eggs in foods including grains and pasta, where larvae hatch to a ready-made meal.
Corn earworm moths in the Noctuidae family harm agriculture. They lay eggs in food crops, and the larvae emerge to eat the vegetation. Thank goodness for bats that gobble up tons of these pesky moths every night.
Most North American moths are harmless and outnumber butterfly species by approximately 11,000 to 765. Unlike butterflies that dazzle us by day, most moths fly at night. They pollinate multiple species of plants and are thereby crucial to our ecological system.
But why do moths flit around streetlamps and porch lights? We don’t know, but one explanation is transverse orientation wherein moths and other nighttime insects maintain flight orientation by the light of stars and the moon. Artificial lights apparently simulate celestial lights.
Which brings us to the luna moth that people frequently see on walls by a porch light. What a handsome moth with its shimmering lime-green color, long streaming and wings spanning 3 to 4 inches. The moth’s twisting tail during a seemingly languid flight disrupts sound waves to disorient the echolocation ability of predatory bats.
The luna moth gets its name from the Roman goddess Luna, often depicted with half-closed eyelids. The namesake moth’s hindwings have small disks with dark edges resembling eyelids or a waxing Gibbous moon, take your pick.
Luna moths are among the group of giant silkworm moths in the Saturniidae family that are relatively common in our area.
Their larvae spin silk cocoons where they pupate and later emerge as moths with captivating colors and wing patterns.
Among other pretty silkworm moths is the Io moth, with a 2-inch tawny wingspan. Big eyespots like the eyes of owls on the hindwings deter predatory songbirds.
My wife and I used to raise cecropia moths with bodies trimmed in red and white and with 5- to 6-inch wingspans of gray-brown accented by red lines. We’d place their cocoons looking like dead-leaf litter on our dining-room windowsill, which inadvertently caused guests to freak out.