Mile-a-minute Vine (Persicaria perfoliata) syn. (Polygonum perfoliatum)

Family: Knotweed family (Polygonaceae)

Description

Mile-a-minute is an annual scrambling vine native to Asia that can grow to 25 feet in length. Small, curved barbs cover the stem, petioles, and leaf undersides. These sharply pointed barbs can rip clothing and skin. The plant’s bluish-green leaf is set on long petioles. It is as long as wide (0.75-3.0 inches) and looks like a slightly forked equilateral triangle. Circular bracts are located at nodes along the stem—the stem pierces through these bracts. Small white flowers are located on stalks that extend above these bracts. By June, the flowers have developed into green berries which turn blue later in the summer. Mile-a-minute infests wood edges, open wetlands, and roadsides.

Reproductive/Dispersal Methods

Birds and mammals eat and spread the fruits. Industrial and landscaping equipment picks up and spreads soil contaminated with mile-a-minute seed.

Similar Species

There are native and non-native species that resemble mile-a-minute, but none of these has the combination of barbs, triangular leaves on long petioles, circular bracts, and blue fruits. The University of Connecticut College of Agriculture and Resources (see Sources and Links below) has a visual guide that distinguishes these species.

Impacts

Mile-a-minute scrambles over and chokes native trees, shrubs, and herbaceous plants. It does best in open, disturbed conditions, where it can dominate acres of wetland and upland habitat.

Distribution

In the Unites States, Mile-a-minute occurs in Oregon and in eastern states from Massachusetts to Virginia, west to Ohio. In Massachusetts, it was first documented on Cape Cod and in Milton in 2006. Since then, it has been found in several more towns as far west as Greenfield.

 

 

Sources and Links

Pennsylvania Department of Conservation and Natural Resources

http://www.dcnr.state.pa.us/cs/groups/public/documents/document/dcnr_010249.pdf

USDA Forest Service-Northeastern Area-State & Private Forestry

http://www.na.fs.fed.us/spfo/pubs/pest_al/mm/pa_mam.pdf

Plant Conservation Alliance Alien Plant Working Group

http://www.nps.gov/plants/alien/fact/pepe1.htm