Noxious Weed ID

What is a noxious weed?

A noxious weed is a non-native plant which has no agricultural or health benefits, and degrades native plant and wildlife habitat while posing a threat to producing lands or human health.​
Who needs to control noxious weeds?​​

It is the landowner’s responsibility to control noxious weeds and noncompliance may be penalized under the Colorado Noxious Weed Act 35-5.5. The Archuleta County Weed and Pest Department controls noxious weed infestations on county property and may be contracted by private landowners. The department also provides herbicides and other pesticides as well as being a resource for alternative methods of control.​

See the presentation for the 2018 Weed Tour for a comprehensive guide of noxious weeds in Archuleta County 

See the presentation for the 2019 Weed Tour for ID of common weeds in Archuleta County as well as management guidelines

The links below describe some of the most common invaders in Archuleta County separated by flower color.​​​​​
Noxious weeds with white flowers:
Oxeye Daisy
​White Top
​Field Bindweed
​​​​​​​Noxious weeds with purple flowers:​​​
Russian Knapweed
​Spotted Knapweed
​Canada Thistle
​Bull Thistle
​Musk Thistle
​Scotch Thistle
​Houndstongue ​​
​Dames Rocket​ ​​​
Noxious weeds with yellow flowers:​​​​
Leafy Spurge
​Yellow Toadflax
​Common Mullein
​Black Henbane ​​​
​​​Noxious grasses:
​Bulbous Bluegrass ​​​
Noxious trees:
Salt Cedar ​​
​Russian Olive​ ​​​​​
​For the entire Colorado Noxious Weed List visit