First Occurrence of Mile-a-Minute Weed Confirmed in Maine, Urgent Action Required

August 8, 2023

For more information contact: Jim Britt at: Jim.Britt@maine.gov

Augusta, Maine - The Department of Agriculture Conservation and Forestry (DACF) has recently verified the first known occurrence of mile-a-minute weed (Persicaria perfoliata) in Maine. This fast-growing invasive vine, native to India, Asia, and the Philippine Islands, poses a significant threat to nurseries, Christmas tree farms, reforestation projects, and restoration areas, as it can smother young plants and trees under its dense growth.

The discovery was made at a private residence in Boothbay Harbor, where the alert landowner reported finding a mile-a-minute weed plant while cleaning up weeds that came with newly installed landscape plants. This invasive species is one of 33 plants listed on the DACF's do-not-sell list, notorious for hitchhiking on nursery stock and spreading rapidly.

Mile-a-minute weed derives its name from its astonishing growth rate of up to 6 inches per day or 25 feet in six to eight weeks. It features distinctive triangular leaves, spikes of pea-sized blue fruits, and recurved barbs along the stems and leaf margins. The vine also displays peculiar circular leaves, known as ocreae, clasping the stem beneath each fruit spike.

Invasive species like mile-a-minute weed have the potential to cause severe harm to Maine's environment and economy. As part of our commitment to controlling and eradicating this invasive plant, the DACF urges the public to report any potential sightings promptly. If you encounter a vine resembling mile-a-minute weed, please visit the Maine Natural Areas webpage for identification information. If the plant matches the description, we encourage you to take photos, note the location, and report the finding via email to Invasives.MNAP@maine.gov or call (207) 287-7545.

"The timely reporting of invasive plants is crucial to our efforts in safeguarding Maine's natural areas," said State Horticulturalist Gary Fish. "With the public's support, we can respond rapidly and take necessary measures to eradicate any other mile-a-minute weed plants in the area."

For more information on mile-a-minute weed and other invasive species of concern in Maine, please visit MNAP's invasives plants webpage, Let's cooperate to protect our state's biodiversity and preserve its natural beauty.

Supporting documents

Mile-a-Minute Weed