Clear Creek County Noxious Weed Lists - November 30 -2009

List A Weeds: 

     All populations of List A species are designated for eradication.  List A species must be eradicated in accordance with all the provisions of the applicable state noxious weed management plans.   Bold font indicates the species is in Clear Creek County. 

(Note:  ~ Tilde symbol indicates mandatory management is required in Colorado)

~ African rue (Peganum harmala)
~ Camelthorn (Alhagi pseudalhagi)
~ Common crupina (Crupina vulgaris)
~ Cypress spurge (Euphorbia cyparissias)
~ Dyer's woad (Isatis tinctoria)
~ Giant salvinia (Salvinia molesta)
~ Hydrilla (Hydrilla verticillata)
~ Meadow knapweed (Centaurea pratensis)
~ Mediterranean sage (Salvia aethiopis)
~ Medusahead (Taeniatherum caput-medusae)
~ Myrtle spurge  (Euphorbia myrsinites)

~ Orange hawkweed  (Hieracium aurantiacum)  -  Map

~ Purple loosestrife (Lythrum salicaria)
~ Rush skeletonweed (Chondrilla juncea)
~ Sericea lespedeza (Lespedeza cuneata)
~ Squarrose knapweed (Centaurea virgata)

~ Tansy ragwort (Senecio jacobaea)
~ Yellow starthistle (Centaurea solstitialis)

List B Weeds (Designated for Eradication): 

            The following species are designated by the Commissioner of Agriculture for eradication (with certain exceptions) in accordance with provisions of the applicable state noxious weed management plans.  Bold font indicates the species is in Clear Creek County:

(Note:  ~ Tilde symbol indicates mandatory management is required in Colorado)

~  Black henbane  (Hyoscyamus niger)

~  Chinese clematis  (Clematis orientalis)  -  Map

~  Diffuse knapweed (Centaurea diffusa)   -   Map

~  Houndstongue  (Cynoglossum officinale) 

~  Oxeye daisy  (Chrysanthemum leucanthemum)  -  Map

~  Perennial pepperweed  (Lepidium latifolium)   -  Map

~  Spotted knapweed  (Centaurea maculosa)  -   Map

~  Yellow toadflax  (Linaria vulgaris)  -  Map

            (1)        All populations of List B species are designated for management unless                              designated for eradication.  List B species must be managed in accordance                         with all the provisions of this Section, including any applicable state                                   noxious weed management plans. Until a state noxious weed management                         plan for a particular species is developed and implemented by rule, all                                 persons are recommended to manage that species after consultation with                            the Weed Management Office.  Bold font indicates the species is in Clear                         Creek County.

                        List B noxious weed species have (or will have) a state noxious weed                                 management plan developed to stop their spread.  Developed plans MUST                         be utilized on the respective species.

List B Weeds:

Absinth wormwood (Artemisia absinthium)
~  Black henbane (Hyoscyamus niger)

~ Bouncingbet (Saponaria officinalis)
Bull thistle (Cirsium vulgare)
Canada thistle (Cirsium arvense)
~ Chinese clematis (Clematis orientalis)  -  Map

Common tansy (Tanacetum vulgare)
Common teasel (Dipsacus fullonum)
Corn chamomile (Anthemis arvensis)
Cutleaf teasel (Dipsacus laciniatus)
~ Dalmatian toadflax   broad-leaved (Linaria dalmatica)  -  Map
Dalmatian toadflax, narrow-leaved (Linaria genistifolia)         

~ Dame's rocket  Dame's rocket (Hesperis matronalis)
~ Diffuse knapweed (Centaurea diffusa)   -   Map

Eurasian watermilfoil (Myriophyllum spicatum)

~ Hoary cress (Cardaria draba)
~ Houndstongue  (Cynoglossum officinale)
~ Leafy spurge  (Euphorbia esula) Mayweed chamomile (Anthemis cotula)

Moth mullein (Verbascum blattaria)
~ Musk thistle  (Carduus nutans)
~ Oxeye daisy  (Chrysanthemum leucanthemum)
~ Perennial pepperweed (Lepidium latifolium)
Plumeless thistle (Carduus acanthoides)
Quackgrass (Elytrigia repens)
Russian knapweed  (Acroptilon repens)

Russian-olive (Elaeagnus angustifolia)
Salt cedar  (Tamarix chinensis, T.parviflora, and T. ramosissima)

~Scentless chamomile (Matricaria perforata)
~Scotch thistle  (Onopordum acanthium)

~Spotted knapweed  (Centaurea maculosa)  -  Map

Spurred anoda (Anoda cristata)
Sulfur cinquefoil  (Potentilla recta)

Venice mallow (Hibiscus trionum)
Wild caraway (Carum carvi)

Yellow nutsedge (Cyperus esculentus)
~Yellow toadflax (Linaria vulgaris)  -  Map

            (2)       Size and Location

                         All landowners and land manager with priority weed species are required
                         to implement the following minimal management strategies.

                        (a)       Isolated small populations of one acre or less:  Intensive best
                                    management practies applied with eradication goals in mind.
                                    Prevent seed formation and root spread on an annual basis.

                        (b)        Satellite populations (one acre or less) proximate to larger                                                     populations:  Intensive best management practices applied with                                           eradication, containment, and reduction goals in mind.  Prevent                                           seed formation and root spread on an annual basis.

                        (c)        Large populations of more than one acre:  Use of effective, best                                          management practices. Apply containment and perimeter buffering                                     management practices at a minimum of fifty feet wide each                                                 growing season.  Prevent seed formation and root spread on an                                           annual basis.

                        Additionally, containment and perimeter buffering/reduction practices                                shall be stepped inward toward the center of the infestation at a minimum                         of fifty feet wide each season thereafter until the desired goals of the weed                         management plan have been met.

            (3)        Priority Management Areas Consists of:

                       (a)          Infestations adjacent to property lines, easements, rights of ways,                                     ditches, canals, streams, rivers, creeks, trails, wildlife migration                                            routes, private and public roadways.  Buffering will be required                                          each growing season and applied to the entire perimeter of the                                             infestation at a minimum of fifty feet wide at the proper timing in                                       order to prevent seed formation and root spread.  Annual stepped                                       in buffering and reduction management is required.

List C Weeds:

               All Populations of List C species are recommended for voluntary management
unless they are designated as mandatory by the Board of County Commissioners.  Bold
font indicates the species is in Clear Creek County

Chicory (Cichorium intybus)
Common burdock (Arctium minus)
Common mullein (Verbascum thapsus)
Common St. Johnswort (Hypericum perforatum)
Downy brome (Bromus tectorum)
Field bindweed  (Convolvulus arvensis)

Halogeton (Halogeton glomeratus)
Johnsongrass (Sorghum halepense)
Jointed goatgrass (Aegilops cylindrica)
Perennial sowthistle (Sonchus arvensis)   

Poison hemlock (Conium maculatum)
Puncturevine (Tribulus terrestris)
~Redstem filaree (Erodium cicutarium)
Velvetleaf (Abutilon theophrasti)
Wild proso millet (Panicum miliaceum)