A pretty pink flower popping up more frequently across Minnesota is actually a “nasty” weed that the state agriculture department is calling a threat to agriculture and the environment.

The spotted knapweed, which is not native to Minnesota, is an aggressive, fast-growing plant that displaces beneficial plants, according to a Minnesota Department of Agriculture press release.

“It is not a good neighbor,” MDA Plant Protection Director Geir Friisoe said in the release. “When it becomes established in an area, it crowds out forage plants and other desirable vegetation.”

As a result, pasture productivity can drop, Friisoe notes, and erosion and habitat degradation are concerns.

The weed hasn’t been identified as a problem in southeastern Minnesota, but Monica Chandler with the MDA plant and weed protection program said it definitely could spread to the area.

“It’s on the move and we really want to get ahead of it,” she said.

Chandler noted that spotted knapweed has been seen popping up along Highway 61 between Wabasha and Winona.

Knapweed can spread in various ways, Chandler said, such as being picked up by vehicles or released into the air when roadside grass is mowed.

The weed, which is native to Europe and Asia, was introduced to northern Minnesota nearly 100 years ago but has only recently become a concern in central Minnesota.

To combat infestations, the MDA employs biocontrol agents — seedhead weevils and root weevils. These insects are natural enemies of knapweed.

Landowners or farmers that notice an infestation can hand-weed the area or, if the problem is too large, use biological control after consulting with a county agricultural inspector.

For more on spotted knapweed, visit www.mda.state.mn .us/plants/badplants/knapweed.htm.