The moth is a federally regulated species due in part to its destructive nature to the boxwood plant, which the state says is a popular ornamental shrub across many environments in Delaware.
Jeffrey Brothers is the Delaware Department of Agriculture’s Plant Industries Administrator.
“Their preferred main host, which is primarily box woods, they can completely defoliate it in a short period of time” he told DPM.
Traps set up on the Kent-New Castle County border caught a handful of the species, which indicates some have begun to spread north. The moth was initially found in Kent County in July 2024.
Brothers says owners of boxwood plants should keep a keen eye this spring looking for potential infestations of the insect so they can take action against them.
“They need to act fast and, really, their only option right now is an insecticide treatment. It’s a caterpillar, so anything that will kill a caterpillar will probably kill the box tree moth caterpillar as well.” he said.
Brothers notes the caterpillars of these moths are distinguishable as bright green with black stripes, white hairs, and a shiny black head, while the adult moth generally has white wings with a brown border; the box tree moth is sometimes confused with the melonworm moth.
Specific recommendations for insecticides and other pest management tools are available by calling the Delaware Cooperative Extension Master Gardeners:
New Castle County: 302-831-8862
Kent County: 302-730-4000
Sussex County: 302-831-338
Isolating an infested shrub and cutting the plant at its base is also an option; your plant should be able to regrow from its roots.
