What is a noxious weed?

Noxious weeds are non-native plants that were brought into Idaho through human actions. Because they grow aggressively and have no natural enemies in our area, these species of plants can be destructive to wildlife habitat, competitive with crops and difficult to control. Legally, a noxious weed is any plant designated by a Federal, State or county government as injurious to public health, agriculture, recreation, wildlife or property. Some characteristics of noxious weeds include:

  • They produce large numbers of new plants each season.
  • They tolerate many soil types and weather conditions.
  • They spread easily and efficiently, usually by wind, water, or animals
  • They grow rapidly, allowing them to displace slower growing plants.
  • Spread rampantly when they are free of the natural checks and balances found in their native range.

Learn more on our Weeds page.

Show All Answers

1. Is there a law in Idaho that requires landowners to control the noxious weeds on their property?
2. I thought the Noxious Weed Control Office took care of all the weeds in the county?
3. Who takes care of the noxious weeds on private roads?
4. What is a noxious weed?
5. How did noxious weeds get here and where did they come from?
6. My neighbor has spotted knapweed it looks bad and it is blowing into my yard. What can I do?
7. The spotted knapweed on my neighbor's property looks awful! Would you please do an inspection and make them spray it?
8. What is a surfactant and why should I use one?
9. Every year I spray the weeds on my property and the next year it seems I have as many or more than before. How can I stop the weeds?
10. I would like to know what types of weeds are growing on my property. Can the Noxious Weed Control Department help me with this?
11. Does your office provide herbicide to private landowners or can they purchase it from the county?
12. Why should I care about noxious weeds? I want my land to be natural!
13. What is an EDRR Weed?