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Noxious Weeds

myrtle spurge growing in a rock garden

Noxious Weeds

Noxious Weeds are non-native plants that threaten our native landscapes and open spaces by disrupting ecosystems. Their presence affects our waterways, wildlife, and recreation. They come to Colorado as seeds in ornamental planting mixes, as nursery stock, or as hitch-hikers on the undercarriage of vehicles. They have been transported from places as far away as Europe, Asia, or Africa and their natural controls, such as insects or diseases, did not arrive with them. Many of them may still be sold in local nurseries for planting in ornamental landscapes.

The Office of the City Naturalist aggressively manages noxious weed infestations within urban Natural Areas, native landscapes and open spaces, as well as in Denver Mountain Parks.

Management efforts lead to significantly reduced noxious weed populations which then allows for Colorado’s native plant species to thrive and provide biodiversity.

We also work to comply with the Colorado Noxious Weed Act which helps us prioritize our management efforts. Noxious weeds are often a symptom of broader ecological or land management issues. By better understanding how natural and man-made disturbances contribute to the introduction and spread of noxious weeds, we will be able to preserve and protect our Denver Parks.

Learn more about DPR's Integrated Pest Management Program (PDF)

View comprehensive list of pesticide/herbicide used (PDF)

Contact Us

Office of the City Naturalist

Kelly Uhing, City Naturalist