Noxious Weeds and Invasive Species Management

Identifying and Managing Noxious Weeds

Noxious weeds and invasive species disrupt native vegetation and ecosystems. Their removal and control is important to protect drinking water supply, agricultural crops, pasture lands and native habitats.

What is a Noxious Weed?

According to the Colorado Noxious Weed Act, a noxious weed is an alien plant or parts of an alien plant that have been designated by rule as being noxious or has been declared a noxious weed by a local advisory board, and meets one or more of the following criteria:

• Aggressively invades or is detrimental to economic crops or native plant communities;
• Is poisonous to livestock;
• Is a carrier of detrimental insects, diseases, or parasites;
• The direct or indirect effect of the presence of this plant is detrimental to the environmentally sound management of natural or agricultural ecosystems.

Identifying a Weed

• View the Colorado Department of Agriculture webpage – Colorado Noxious Weed List

Controlling Noxious Weeds

According to the Colorado Department of Agriculture website, there is no one best way to rid the state of noxious weeds. Weeds, like all plants, vary in how they reproduce, have varying root structures (extensive root systems or a single taproot), and how they respond to herbicides. That’s why an integrated weed management approach is necessary. This approach assesses the best techniques for a given species, from a choice of manual (mowing, pulling, digging up), cultural (land management practices such as irrigation, cultivation, types of cover or crops), biological (using plant pests that are native to the source of the weed); or chemical (herbicides). Other tools and techniques can be used on larger, woody weeds such as Russian olive and tamarisk.

Noxious Weed Management on Boulder County Open Space

Boulder County Parks and Open Space is responsible for weed management on open space areas, certain agricultural leased lands, and designated county maintained roads.

• Learn how noxious weeds are managed on open space property.

Noxious Weeds of Colorado Guide

The Noxious Weeds of Colorado Guide can be purchased through the Colorado Weed Managment Association.

Report a Concern

Report issues or concerns to the Boulder County Community Planning & Permitting Department:

• Online form: Report a Community Planning and Permitting Code Violation
• Phone: 303-441-3930
• Mail:
  Code Enfocement, Community Planning and Permitting
  PO Box 471
  Boulder, CO 80306