Click on the common name of the noxious weed below and you will be directed to the Colorado Department of Agriculture's description of that species.  

List “A” Species

Myrtle Spurge (Euphorbia myrsinites)          

Orange hawkweed (Hieracium aurantiacum)             

List “B” Species

Absinth wormwood (Artemisia absinthium) 

Black henbane (Hyoscyamus niger) 

Bull thistle (Cirsium vulgare)

Canada thistle (Cirsium arvense) 

Chamomile Daisy: Scentless and Mayweed  (Tripleurospermum perforatum and Anthemis cotula)

Chinese clematis (Clematis orientalis)

Common tansy (Tanacetum vulgare) 

Dalmatian toadflax (Linaria dalmatica) 

Dame’s rocket (Hesperis matronalis) 

Diffuse knapweed (Centaurea diffusa) 

Hoary cress/Whitetop (Cardaria draba) 

Houndstongue (Cynoglossum officinale) 

Leafy spurge (Euphorbia esula) 

Musk thistle (Carduus nutans) 

Oxeye daisy (Leucanthemum vulgare) 

Perennial pepperweed (Lepidium latifolium) 

Plumeless thistle (Carduus acanthoides) 

Russian knapweed (Acroptilon repens) 

Russian Olive (Elaeagnus angustifolia) 

Scotch thistle (Onopordum acanthium, tauricum) 

Spotted knapweed (Centaurea stoebe) 

Sulfur cinquefoil (Potentilla recta) 

Tamarisk/Salt Cedar (Tamarix ramosissima) 

Wild caraway (Carum carvi) 

Yellow toadflax (Linaria vulgaris) 

List “C” Species

Cheatgrass/Downy brome (Bromus tectorum)  

Common mullein (Verbascum thapsus)         

Field bindweed (Convolvulus arvensis)

Poison hemlock (Conium maculatum)