Invasive Species

What Is an Invasive Species?

An invasive species is a plant or animal species that is not native to our area and has negative effects on health, the environment, and/or the economy.

Invasive species arrive in our area without the natural predators and diseases that would keep their populations in balance in their native homelands. They can reproduce rapidly, causing major changes to land or aquatic systems and impacting the native plants and animals in those systems.

Why Should I Care About Invasive Species?

Invasive species impact us in many complex ways.

  • Health risks. Some invasive species pose health risks to humans or animals. Wild parsnip, for example, can cause severe burns on human skin.
  • Agriculture. Species such as Canada thistle invade farm fields, lowering yields and requiring time and money to control.
  • Range lands and grass lands. Species such as leafy spurge and spotted knapweed can wreak havoc on ranch lands and native prairie, out-competing desirable vegetation and reducing forage yields and quality.
  • Natural areas. Species such as buckthorn and garlic mustard have spread aggressively in our native woodlands, crowding out native plants, leading to significant decreases in native shrubs and ground covers.
  • Recreation. Invasive aquatic plants such as Eurasian water milfoil can impact fishing and boating by degrading fish habitat and clogging boat motors.

The Midwest Invasive Plant Network (MIPN) has published an excellent booklet to address why we should care about invasive species: InvasivesBrochure.pdf ( 

Invasive Species Rules & Regulations

The City of Maplewood encourages residents and businesses to control invasive species on their properties. Some invasive plants are also considered noxious weeds. State law and Maplewood ordinance (Section 18-31) require that residents and businesses control noxious weeds on their property.

  • The Minnesota Noxious Weed Law lists invasive terrestrial plant species that are regulated in the state. They are divided into categories: Eradicate, Control, Restricted, and Specially Regulated. New species moving into Minnesota undergo a thorough scientific assessment by the Minnesota Invasive Species Advisory Council (MISAC) to determine whether it is necessary to add them to the list. Several of the species on this list are present in Maplewood.
  • The United States Department of Agriculture also prohibits importation and transport of some plant species in the United States through the Federal Noxious Weed Law.
  • The Minnesota Department of Natural Resources MN DNR) regulates aquatic invasive species (AIS). Prevention of invasive species spread is the most successful and cost-effective means to control invasive species. A Clean-Drain-Dry boat cleaning station will be installed at the Silver Lake boat launch at Joy Park in 2023. Information on Minnesota aquatic invasive species is available from the MN DNR website: Aquatic Invasive Species | Minnesota DNR ( and the Minnesota Aquatic Invasive Species Research Center (MAISRC): Finding Solutions to Minnesota’s Aquatic Invasive Species Problems. | Minnesota Aquatic Invasive Species Research Center (MAISRC) (

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