Natives, Aliens and Noxious Plants

Non-native plants, also called introduced or alien plants, are plant species that were introduced into an area by humans either accidentally or deliberately.

A native plant is one that naturally occurred in an area prior to European-American settlement.

A weed is a plant growing in an undesirable location – it can be non-native or native, and what some people consider a weed in one location is a valuable plant in another location. Red alder, for example, is an important native pioneer and streamside tree in Western Washington but is considered a nuisance weed by many people because it spreads aggressively and grows quickly in fields, driveways, and yards.

Noxious weed is a legal term that is used to describe an invasive, non-native plant species that threatens our natural resources or economy – the plant’s presence poses a risk to agricultural production, water quality, or ecology. Washington State as well as each County maintains a noxious weed list.

You can learn more about Noxious Weeds and Noxious weed identification at the Washington State Noxious Weed Control Board Website or Snohomish County Noxious Weed Control Board

Graphic showing the difference between invasive and noxious weeds