Summit County Noxious Weeds

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Noxious weeds are non-native plants that disrupt native vegetation because they have no natural controls and are able to adapt to varied conditions.  


As a result of the Colorado Noxious Weed Act, these weeds have been placed on three separate lists.

List A Plants: Eliminate everywhere

List B Plants: Spread should be stopped

List C Plants: Control is recommended

The Summit County Weed Brochure (pdf) contains a list of noxious weeds found in Summit County and includes photos and characteristics to help identify noxious weeds.  Call Summit County Weed Control at (970)668-4218 to inquire about the best method of eradication for each weed species.

Daisy Comparison
If you are confused about whether or not your daisies are noxious, take a look at these photos (pdf) - Oxeye Daisy and Scentless Chamomile are noxious weeds; Shasta Daisy is not!

Thistles - Native or Non-Native?

Colorado's native thistle species are valuable to pollinators, seed-feeders and browsing wildlife.  However, several non-native species threaten agriculture and natural areas.  Use this Thistle Identification and Management Guide (pdf) to learn the difference between native and non-native thistles.