ST PAUL, Minn. — An invasive insect that feeds on lilies and other popular plants has been discovered in Minnesota for the first time.
The Minnesota Department of Agriculture (MDA) says a St. Paul resident recently noticed an unusual insect on an Asiatic lily and called the department. Inspectors responded and confirmed the presence of an adult lily leaf beetle.
MDA says the invasive insect is native to Europe and Asia, but is currently found in Canada, the northeastern United States, Washington state and Wisconsin. Lily leaf beetle larvae cause significant damage to true lilies and fritillaries. Adult beetles are known to occasionally feed on other plants, like hollyhocks, hostas, lily of the valley, potato and Solomon's seal.
They do not do damage to daylilies, canna lilies, or calla lilies, according to MDA.
“This insect is a major concern for gardeners and homeowners with lilies,” said Angie Ambourn, Supervisor of the MDA’s Pest Detection Unit. “Both lily leaf beetle adults and larvae chew irregular holes and notches in lily leaves, stems, and developing buds, but larvae cause the most damage to plants and can completely defoliate plants and destroy flowers.”
MDA says adult lily leaf beetles are bright red and very distinctive-looking. The insect's eggs are reddish and laid in lines on the undersides of leaves. Bumpy, black lily leaf larvae can also be found on the undersides of leaves. The larvae cover themselves with their own excrement, likely to protect themselves from predators.
Since this is the first reported discovery of lily leaf beetle in Minnesota, MDA officials want to better understand where this insect may be and how widespread the problem is. Residents can report suspected lily leaf beetles via email, or by calling the MDA’s Arrest the Pest line at 1-888-545-6684. Those spotting the invasive bug are urged to include clear photos.
For more on the lily leaf beetle, check out the MDA website.