Common Invasive Plants
Common Invasives
A quick list highlighting some of Minnesota’s most common invasive plants. Learn more about invasives and find other invasive species at the Minnesota Department of Natural Resources invasive species page.

Garlic Mustard (Alliaria petiolata)
Characteristics
- Appearance: kidney-shaped leaves with scalloped edge, grows 12-32 inches tall with white flowers at the top
- Spreads by transporting seeds that are stuck in mud
- Grows in thick clumps that shade and outcompete native plants
- Produces a chemical that stunts the growth of neighboring plants
Removal/Prevention
- Clean your boots, pets, and vehicles to remove any seeds
- Hand-pull entire plant, including roots
- Bag plants and let them decay or burn them, do not leave them on the ground

Common Buckthorn (Rhamnus cathartica)
Characteristics
- Appearance: tall shrub or small tree that reaches 20 feet tall, has dark green and glossy leaves, and produces red to dark purple fruit clusters
- Seeds can be spread by birds or wildlife
- Degrades wildlife habitat and contributes to erosion by outcompeting plants that grow on the forest floor
- Is a host plant for pests and fungus
- Has no natural controllers, like insects or disease, to curb its growth
Removal/Prevention
- Removal method depends on size
- If less than 3/8 inch in diameter, it can be removed by hand
- If greater than 3/8 inch in diameter, it can be removed with an uprooting tool
- If 2 inches or greater in diameter, cut the stem at the soil level and cover the stump to prevent resprouting
- Rooted or cut plants can be placed in a designated area to allow for decay
- Regular maintenance and monitoring is required, since the seeds can survive for two years before germinating

Wild Parsnip (Pastinaca sativa)
Characteristics
- Spends its first year as a clump of low-lying leaves then forms a stalk that produces small yellow flowers
- Seeds are viable in the soil for up to four years and are spread by human and animal movement, wind, and water
- Spreads rapidly and severely modifies habitats
- When in direct sunlight, sap can cause chemical burns that produces red rashes, blistering, and skin discoloration
Removal/Prevention
- Wear protective gloves, long sleeves, and pants when removing wild parsnip
- Clean off your shoes, pets, and vehicles to remove any seeds
- Pull, cut, or mow the plant for removal

Knotweed (Polygonum spp.)
Characteristics
- Appearance: large non-woody plant with many small white to greenish flowers at the base of the leaves
- Can spread vegetatively through rhizome root system and through seed dispersal
- Contributes to erosion of shorelines and makes them more susceptible to flood damage by suppressing growth of low-lying vegetation
- Can grow through concrete and building foundations, causing structural damage
Removal/Prevention
- Small infestations can be managed by digging or pulling the plant by hand
- Plants can resprout from stem fragments as small as 1/2 inch long, so mowing is not recommended
- Burn or cover piles of plants with a tarp to allow for decay

Creeping Bellflower (Campanula rapunculoides)
Characteristics
- Appearance: 2 to 3 foot tall flowering plant with bell-shaped, blue-purple flowers
- One plant produces up to 15,000 seeds and is hard to eradicate once established
- Spreads through extensive rhizome root system and through seed dispersal
- Outcompetes native species by forming dense stands
Removal/Prevention
- Hand removal is effective for small patches, ensuring all parts of the roots are removed to prevent regrowth
- Smother plant with a tarp