Boxelder Leafminer: Appearance, Territory, Damage and Life Cycle

Latin Name: Caloptilia Negundella

Appearance: Caloptilia Negundella (Boxelder Leafroller Moth) is a Lepidoptera species of the leaf blotch miner moth family. The Boxelder Leafroller Moth is 5.5 mm long, with a smooth scaled vertex, an inverted labial palpi, nearly straight segments, and a purple-brown and yellow pattern on the proboscis. The adult is a tiny orange to yellow fly that emerges in early May. Eggs are deposited, and the larval stage proceeds to mine leaf tissue. The boxwood leafminer is a little yellow to orange maggot that lives inside mined leaves.

Hosts Plants: Larvae are leaf miners on Boxelder.

Territory: West of Mississippi, into Ohio, in southern Canada and the United States.

Damage Insect Cause: Leafminers eat green tissue from the spaces between the top and lower leaf surfaces. The presence of yellow to brownish blotch like mines or a blistered, thickened look to the top surface of leaves indicate leafminer feeding. The damage is mostly cosmetic, but severe infestations on a regular basis might harm bushes. Pick off infected leaves or shear affected terminals before the flies arrive. The clippings should be taken out and discarded. Plant resistant variations include ‘Suffruticosa,’ ‘Pendula,’ and ‘Argenteo-variegata.’

Life History and Habits: The bug spends the winter as a larval in the mined leaves. They become active and develop quickly in the spring. Before the adult fly emerges, the orange pupae may be seen clinging to the leaf. Female flies place their eggs on the top of the current season’s development. Throughout the summer, the larvae hatch and mine the leaves. Each year, one generation is born.