New invasive insect found in Minnesota for first time

The caterpillar of the purple carrot-seed moth
The caterpillar of the purple carrot-seed moth. Minnesota agriculture officials announced Wednesday that the invasive moth had been confirmed in the state for the first time.
Courtesy of PJ Liesch, UW Insect Diagnostic Lab

Agriculture officials are asking Minnesotans to be on the lookout for an invasive moth species that's been found in the state for the first time.

The purple carrot-seed moth feeds on plants in the carrot family — that includes dill, fennel and coriander. A resident near Stillwater found one of the insects on their dill plants and reported it to the Minnesota Department of Agriculture; a few days later, another was found in Montgomery, Minn.

A purple carrot-seed moth
A purple carrot-seed moth
Courtesy of PJ Liesch, UW Insect Diagnostic Lab

The moth is native to western Europe, China and Russia, but turned up in North America 14 years ago. It was first detected in Wisconsin in 2018, and Iowa in 2020.

“The impact of this insect is currently unknown, but because it is associated with the flowers and not the roots of plants, impact on carrots, celery, and parsnip crops should be minimal,” Angie Ambourn, supervisor of the state Agriculture Department's Pest Detection Unit, said in a news release. “Crops that are commonly grown for seed, like fennel, dill and coriander, might be where we see the greater impact.”

The moth's caterpillars are dark green or reddish, with many white spots on their bodies. They feed on the plants' flowers and also create webbing on the flowers, potentially rendering herbs unusable. The caterpillars pupate in that webbing and then emerge as moths.

Ag officials are asking anyone who sees the moths or caterpillars to report them to the Minnesota Department of Agriculture online, or by calling (888) 545-6684.

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