An invasive beetle that feeds on and damages lilies and fritillaries has been discovered for the first time in Minnesota.
An adult lily leaf beetle was found in St. Paul after a resident reported an insect on their Asiatic lily to the Minnesota Department of Agriculture (MDA), a news release said.
“This insect is a major concern for gardeners and homeowners with lilies,” Angie Ambourn, supervisor of the MDA’s Pest Detection Unit, said in the release. “Both lily leaf beetle adults and larvae chew irregular holes and notches in lily leaves, stems, and developing buds."
But the MDA says the beetle's larvae are the problem as they can completely defoliate true lilies and fritillaries – though they don't damage daylilies, canna lilies or calla lilies. The adult beetles do occasionally feed on other plants, such as hollyhocks, hostas, lily of the valley, potato, and Solomon's seal.
The "distinctive-looking" lily leaf beetle is native to Europe and Asia. It was first found in North America (Canada) in the 1940s and now is found in most of Canada, including Thunder Bay, Ontario, and Winnipeg, Manitoba, as well as Wisconsin, Washington and the northeastern United States. It was first found in Wisconsin, near Wausau, in 2014, MDA's website notes.
Now that the beetle has been reported in Minnesota, MDA is hoping to better understand where it may be in the state and how big of an issue it is for homeowners.
Look for bright red beetles (the adults), reddish eggs laid in lines on the undersides of leaves and bumpy, black larvae, also on the underside of leaves (the larvae cover themselves in their own excrement, likely to protect against predators).