Steele County SWCD
235 Cedardale Dr.
Owatonna, MN 55060

Ph: (507) 451-6730 - Ext.3

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Noxious Weed Program


It is against the law not to eradicate, control or restrict certain weeds in the state of Minnesota.

Please review this site -

Failure to comply with the Minnesota Noxious Weed Law may result in an enforcement action by a county or local municipality. Fines may be given.

Invasive Species

Buckthorn Buckthorn Berries

Common buckthorn (Rhamnus cathartica) was first brought to Minnesota from Europe in the mid‐1800s as a very popular hedging material. Shortly after its introduction here, it was found to be quite invasive in natural areas. The nursery industry stopped selling it in the 1930s, but many buckthorn hedges may still be found in older neighborhoods throughout Minnesota.

Glossy buckthorn (Frangula alnus), also from Europe, has been sold by the nursery trade in two different forms. The cultivar Columnaris has a narrow and tall form; the cultivar Aspenifolia spreads up to 10 feet and has narrow leaves that give it a ferny texture. This buckthorn aggressively invades wetlands including acidic bogs, fens and sedge meadows.

Why is buckthorn such a problem?
  • Out‐competes native plants for nutrients, light, and moisture
  • Degrades wildlife habitat
  • Threatens the future of forests, wetlands, prairies, and other natural habitats
  • Contributes to erosion by shading out other plants that grow on the forest floor
  • Serves as host to other pests, such as crown rust fungus and soybean aphid
  • Forms an impenetrable layer of vegetation
  • Lacks "natural controls" like insects or disease that would curb its growth
  • Buckthorn leafs out early and retains leaves late into the fall creating dense shade that helps it to out‐compete many native plants.

Regulations European or common buckthorn and glossy or alder buckthorn are listed as restricted noxious weeds in Minnesota. It is illegal to import, sell, or transport buckthorn in Minnesota.

Buckthorn is one of the most invasive species found in Minnesota.

Wild Parsnip  

Appearance: Monocarpic perennial herbaceous plant (plant spends one or more years in rosette stage, blooms under favorable conditions, and then dies), 6" high in the rosette stage and 4' high on stout, grooved stems in the flowering stage.

Leaves: Alternate, leaf is made up of 5 -15 egg shaped leaflets along both sides of a common stalk; leaflets sharply-toothed or lobed at the margins; upper leaves smaller.

Flowers: Flat-topped broad flower cluster 2 - 6" wide, numerous five-petaled yellow flowers; bloom from June to late summer.

Seeds: Small, flat, round, slightly ribbed, straw colored, abundant. Take 3 weeks to ripen before they can reseed; viable in the soil for 4 years.

Roots: Long, thick, edible taproot.

Warning - Avoid skin contact with the toxic sap of the plant tissue by wearing gloves, long sleeves and long pants. The juice of wild parsnip in contact with skin in the presence of sunlight can cause a rash and blistering and discoloration of the skin (phytophotodermatitis).

Ecological Threat:
  • Well established prairies are not likely to be invaded by wild parsnip, but it readily moves into disturbed habitats, along edges and or in disturbed patches. It invades slowly, but once population builds it spreads rapidly and can severely modify open dry, moist, and wet‐moist habitats.
  • It is primarily a problem in southeastern Minnesota in prairies and oak openings.
  • A native of Europe and Asia this plant has escaped from cultivation, it is grown as root vegetable.
Control Methods:
  • Mechanical: Do nothing in healthy prairies; natives can sometimes out compete the parsnip
  • Hand pulling and removing of plants
  • Cut the plant below the root crown before seeds set, and remove the cut plant
  • Mow or cut the base of the flowering stem and remove
  • Chemical: Use sparingly in quality habitats. Spot application with glyphosate or selective metsulfuron after a prescribed burn, parsnip is one of the first plants to green up

Queen Ann's Lace from Europe (Daucus carota) (Wild Carrot)

Appearance: Biennial herbaceous plant, 3 - 4' tall, consists of one or several hairy hollow stems, growing from one central stem, each with an umbrella-shaped flower cluster at the top. Plant smells like a carrot, it is the ancestor of the garden carrot. It appears as rosette in its first year. Its flowers and sets seed the second year.

Leaves: Alternate, start immediately below the flower, increasing in size down the stem. They are pinnately divided (leaflets are arranged on both sides of a common stalk).

Flowers: Compound, flat-topped umbels (small umbels within a large umbel) umbels becoming concave when mature; bloom May through October.

Seeds: Barbed small seeds, promotes dispersal by animals and wind. Seeds stay viable in the soil for 1-2 years.

Roots: Slender, woody taproot, carrot-like in smell and taste.

Ecological Threat:
  • It invades disturbed dry prairies, abandoned fields, waste places, and road sides. It is a threat to recovering grasslands and can be persistent on clay soils.
  • A native of Europe and Asia it now occurs throughout the U.S.
  • It tends to decline as native grasses and herbaceous plants become established.
  • Queen Ann's lace is on the MDA Secondary noxious weeds list in Minnesota.
Control Methods:
  • Mechanical
  • Hand pulling or mowing in mid to late summer before seed set