HomeMy WebLinkAbout1.23 Weed Management PlanPrepared for:
Spring Valley Holdings, LLC.
2600 South Oakhurst Court #14
Glenwood Springs, Colorado 81601
January 18, 2022
Prepared by:
SGM
118 West 6th St., Suite 200
Glenwood Springs, CO 81601
970-384-9017
2021-677.001
Weed Management Plan
Spring Valley Ranch PUD
Garfield County, Colorado
Table of Contents
1.0 Summary ............................................................................................................................. 1
2.0 Description of Survey Area .................................................................................................. 2
3.0 Results of Surveys ................................................................................................................ 4
4.0 Noxious Weed Management Recomendations ................................................................... 6
List of Tables
Table 1 – Noxious Weeds Present on Property ............................................................................................ 1
List of Figures
Figure 1 – Project Area Overview ................................................................................................................. 3
Figure 2 – Noxious Weed Occurrences ......................................................................................................... 5
Appendix
Appendix A – Colorado Listed Noxious Weeds .................................................................................... 7
Appendix B – Garfield County Listed Noxious Weeds .......................................................................... 8
Appendix C - Photo Documentation .................................................................................................. 9
Spring Valley Ranch Weed Management Plan
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1.0 SUMMARY
This Weed Management Plan was prepared at the request of Spring Valley Ranch PUD to fulfill the submittal
requirements of the Land Use and Development Code (LUDC). Spring Valley Ranch is proposing to develop
the existing pastures and associated areas into potential residential use. The proposed project is located in
Garfield County, Colorado in Sections 21, 22, 27, 28, 33 and 34, Township 6 South, Range 88 West (6th
Principal Meridian) (Figure 1).
SGM was retained by Spring Valley Ranch PUD to conduct a noxious weed survey to fulfill requirements of
Garfield County’s LUDC and Vegetation Management department. A field survey documenting and mapping
noxious weeds was conducted on November 4th, 2022, by Rachel Kattnig, SGM Environmental Consultant
III.
Both Garfield County’s noxious weed list and the State of Colorado’s noxious weed list were utilized for
survey efforts (Appendix A and B). To summarize, surveys found the following State and Garfield County
listed noxious weeds:
Table 1 – Noxious Weeds Present on Property
Noxious Weeds
Common Name Scientific Name Colorado Listed
Species
Garfield County
Listed Species
Cheatgrass Anisantha (Bromus) tectorum Yes (List C) -
Common mullein Verbascum thapsus Yes (List C) -
Plumeless thistle Carduus acanthoides Yes (List B) Yes
Canada thistle Cirsium arvense Yes (List B) Yes
Houndstongue Cynoglossum officianale Yes (List B) Yes
Field bindweed Convolvulus arvensis Yes (List C) -
Redstem filaree Erodium cicutrium Yes (List C) -
Scotch thistle Onopordum acanthium Yes (List B) Yes
Spring Valley Ranch Weed Management Plan
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2.0 DESCRIPTION OF SURVEY AREA
The property generally has four separate vegetation types. A large portion of the lower property is
dominated by grazed pasture areas with gently sloping topography, located on alluvial/colluvial material
which has been leveled by deposition. Pasture areas are dominated by agricultural cultivars including
smooth brome (Bromus inermis), orchardgrass (Dactylis glomerata), western wheatgrass (Pascopyrum
smithii), as well as some native fescues (Festuca spp.). The steep slopes above the pastures are dominated
by Gambel oak (Quercus gambelii) with mixed shrub component of sparse pinyon-juniper woodlands (Pinus
edulis and Sabina osteosperma), mountain mahogany (Cercocarpus montanus and C. ledifolius) and Utah
serviceberry (Amelanchier utahensis); these areas have minimal understory vegetation. The transitional
areas between the mixed mountain shrublands and pastures contain remnant stands of sagebrush
shrublands (Artemisia tridentata ssp. bonvillensis). The portion of the property immediately adjacent to
irrigation ditches support sparse wetland vegetation.
Typical conditions in Gambel oak woodlands on steep
slopes.
Typical conditions in pasture areas.
Typical conditions along irrigation ditches. Typical conditions in transitional areas of sagebrush
shrublands.
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Spring Valley Ranch Weed Management Plan
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3.0 RESULTS OF SURVEYS
The most common noxious weeds found within the project area include: cheatgrass, plumeless thistle,
houndstongue, and common mullein. The edges of irrigation ditches were noted as an area with a high
concentration of weeds, particularly Canada thistle. The pasture areas have widespread, low to high
densities of Scotch and plumeless thistle, low densities of cheatgrass, and some isolated areas of field
bindweed. Areas dominated by Gambel oak shrub communities, especially along two track roads and
pasture boundaries, have medium densities of houndstongue. Cheatgrass is present in low to medium
densities throughout the project area, in pastures, along the two track roads, and within native
shrublands. Common mullein occurs in pasture areas or and along two track roads. Figure 2 shows the
areas of noxious weed infestations and relative densities. Redstem filaree was present in two areas along
the two track roads. Nuisance species, notably Russian thistle (Kali tragus) was documented along the
two-track road in two locations. (Appendix C is a photo log documenting the noxious weed presence and
densities throughout the project area.
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Spring Valley Ranch Weed Management Plan
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4.0 NOXIOUS WEED MANAGEMENT RECOMMENDATIONS
To meet the requirements of the Colorado Noxious Weed Act and Garfield County guidance, the developer
shall conduct prescribed management techniques for noxious weeds included on one of three State weed
lists: List A – designated for statewide eradication; List B – managed to prevent further spread and, for
selected species, designated for eradication in large areas; and List C – of more localized concern, but for
which the State will provide education, research, and biological control assistance to jurisdictions that
choose to manage the species. The current State list is available in Appendix A.
If populations of List A species are present in the project area, every population shall be eradicated prior to
seed development. To stop the spread of List B species, populations of every species designated for
eradication in a particular county shall be eliminated prior to seed development.
Additionally, to meet reclamation objectives, the developer should eliminate or minimize those noxious and
invasive weeds designated as “undesirable species”. Undesirable species include redstem filaree, all List C
species (e.g., cheatgrass and field bindweed), and invasive species that commonly colonize disturbed or
reclaimed land and impede or prevent establishment of desirable species.
Control of invasive species is a difficult task and requires on-going control measures. Care must be taken to
avoid negatively impacting desirable plant communities and inviting infestation by other pioneer invaders.
Weed management is best achieved by employing aggressive control early on, and persistent control efforts
over several growing seasons, including direct treatments, prevention through best management practices,
monitoring of treatment efficacy, and subsequent detection efforts. Weed management is often limited to
controlling existing infestations and prevention of further infestations, rather than eradication, but through
effective weed management practices and eradication can be possible in small to medium sized weed
populations.
The following methods are recommended to manage noxious weeds, per Colorado State University’s
Extension program. The Garfield County Vegetation Management Program and the Garfield County Noxious
Weed Management Plan should be reviewed for additional guidance.
Preventive:
Methods include maintaining healthy pastures, using weed-free crop seed, weed-free manure and hay, and
clean harvesting and tillage equipment, as well as the elimination of weed infestations in areas bordering
cropland, and in irrigation ditches and canals.
Chemical:
Herbicide treatments can be highly effective and will vary based on time of year of treatment and species
treatment. Two yearly treatments would be recommended for the duration of the project, one in spring and
one in fall.
Cultural:
Methods include: Establishing and managing an adequate population of desirable vegetation to compete
with the weeds; utilizing livestock (cattle, goats, sheep) when possible; mulching; burning; and even plastic
weed barriers.
Mechanical:
Methods include: Hand-pull, hoe, mow and tillage.
Biological:
Biological weed control involves the utilization of natural enemies for the control of specific weed species.
This method can take many years to result in weed control and is often not 100% effective. However, this
method can dramatically help reduce weed densities and when combined with other methods can be very
beneficial. Methods include grazing, introduction of registered insects or diseases. Contact the Palisade
Insectary for more information.
Spring Valley Ranch Weed Management Plan
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APPENDIX A – COLORADO LISTED NOXIOUS WEEDS
Colorado Noxious Weeds (including Watch List), effective June, 2020
List A Species (25)
Common Scientific
African rue (Peganum harmala)
Bohemian knotweed (Fallopia x bohemicum)
Camelthorn (Alhagi maurorum)
Common crupina (Crupina vulgaris)
Cypress spurge (Euphorbia cyparissias)
Dyer's woad (Isatis tinctoria)
Elongated mustard (Brassica elongata)
Flowering rush (Butomus umbellatus)
Giant knotweed (Fallopia sachalinensis)
Giant reed (Arundo donax)
Giant salvinia (Salvinia molesta)
Hairy willow-herb (Epilobium hirsutum)
Hydrilla (Hydrilla verticillata)
Japanese knotweed (Fallopia japonica)
Meadow knapweed (Centaurea x moncktonii)
Mediterranean sage (Salvia aethiopis)
Medusahead (Taeniatherum caput-medusae)
Myrtle spurge (Euphorbia myrsinites)
Orange hawkweed (Hieracium aurantiacum)
Parrotfeather (Myriophyllum aquaticum)
Purple loosestrife (Lythrum salicaria)
Rush skeletonweed (Chondrilla juncea)
Squarrose knapweed (Centaurea virgata)
Tansy ragwort (Senecio jacobaea)
Yellow starthistle (Centaurea solstitialis)
List B Species (38)
Common Scientific
Absinth wormwood (Artemisia absinthium)
Black henbane (Hyoscyamus niger)
Bouncingbet (Saponaria officinalis)
Bull thistle (Cirsium vulgare)
Canada thistle (Cirsium arvense)
Chinese clematis (Clematis orientalis)
Common tansy (Tanacetum vulgare)
Common teasel (Dipsacus fullonum)
Cutleaf teasel (Dipsacus laciniatus)
Dalmatian toadflax, broad-leaved (Linaria dalmatica)
Dalmatian toadflax, narrow-leaved (Linaria genistifolia)
Dame's rocket (Hesperis matronalis)
Diffuse knapweed (Centaurea diffusa)
Eurasian watermilfoil (Myriophyllum spicatum)
Hoary cress (Cardaria draba)
Houndstongue (Cynoglossum officinale)
Colorado Noxious Weeds (including Watch List), effective June, 2020
List B Species Continued (38)
Common Scientific
Jointed goatgrass (Aegilops cylindrica)
Leafy spurge (Euphorbia esula)
Mayweed chamomile (Anthemis cotula)
Moth mullein (Verbascum blattaria)
Musk thistle (Carduus nutans)
Oxeye daisy (Leucanthemum vulgare)
Perennial pepperweed (Lepidium latifolium)
Plumeless thistle (Carduus acanthoides)
Russian knapweed (Rhaponticum repens)
Russian-olive (Elaeagnus angustifolia)
Salt cedar (Tamarix. ramosissima)
Salt cedar (T. chinensis)
Scentless chamomile (Tripleurospermum inodorum)
Scotch thistle (Onopordum acanthium)
Scotch thistle (O. tauricum)
Spotted knapweed (Centaurea stoebe L. ssp. micranthos)
Spotted x diffuse knapweed hybrid (Centaurea x psammogena)
Sulfur cinquefoil (Potentilla recta)
Wild caraway (Carum carvi)
Yellow nutsedge (Cyperus esculentus)
Yellow toadflax (Linaria vulgaris)
Yellow x Dalmatian toadflax hybrid (Linaria vulgaris x L. dalmatica)
List C Species (16)
Common Scientific
Bulbous bluegrass (Poa bulbosa)
Chicory (Cichorium intybus)
Common burdock (Arctium minus)
Common mullein (Verbascum thapsus)
Common St. Johnswort (Hypericum perforatum)
Downy brome, cheatgrass (Bromus tectorum)
Field bindweed (Convolvulus arvensis)
Halogeton (Halogeton glomeratus)
Johnsongrass (Sorghum halepense)
Perennial sowthistle (Sonchus arvensis)
Poison hemlock (Conium maculatum)
Puncturevine (Tribulus terrestris)
Quackgrass (Elymus repens)
Redstem filaree (Erodium cicutarium)
Velvetleaf (Abutilon theophrasti)
Wild proso millet (Panicum miliaceum)
Colorado Noxious Weeds (including Watch List), effective June, 2020
Watch List Species (19)
Common Scientific
Baby's breath (Gypsophila paniculata)
Caucasian bluestem (Bothriochloa bladhii)
Common bugloss (Anchusa officinalis)
Common reed (Phragmites australis)
Garden loosestrife (Lysimachia vulgaris)
Garlic mustard (Alliaria petiolata)
Himalayan blackberry (Rubus armeniacus)
Hoary alyssum (Berteroa incana L.)
Meadow hawkweed (Hieracium caespitosum)
Onionweed (Asphodelus fistulosus)
Siberian elm (Ulmus pumila)
Scotch broom (Cytisus scoparius)
Swainsonpea (Sphaerophysa salsula)
Syrian beancaper (Zygophyllum fabago)
Tree of Heaven (Ailanthus altissima)
Ventenata grass (Ventenata dubia)
White bryony (Bryonia alba)
Yellow bluestem (Bothriochloa ischaemum)
Yellow flag iris (Iris pseudacorus)
Spring Valley Ranch Weed Management Plan
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APPENDIX B – GARFIELD COUNTY LISTED NOXIOUS WEEDS
Garfield County Listed Species (40)
Common Scientific
Absinth wormwood (Artemesia absinthium)
Black henbane (Hyoscyamus niger)
Bouncingbet (Saponaria officinalis)
Bull thistle (Cirsium vulgare)
Canada thistle (Cirsium arvense)
Chicory (Cichorium intybus)
Chinese clematis (Clematis orientalis)
Common burdock (Arctium minus)
Common tansy (Tanacetum vulgare)
Common teasel (Dipsacus fullonum)
Corn chamomile (Anthemis arvensis)
Curly dock (Rumex crispus)
Cutleaf teasel (Dipsacus laciniatus)
Cypress spurge (Euphorbia cyparissias)
Dalmatian toadflax (Linaria dalmatica)
Dame’s rocket (Hesperis matronalis)
Diffuse knapweed (Centaurea diffusa)
Hoary cress (Cardaria draba)
Houndstongue (Cynoglossum officinale)
Jointed goatgrass (Aegilops cylindrica)
Leafy spurge (Euphorbia esula)
Mayweed chamomile (Anthemis cotula)
Meadow knapweed (Centaurea pratensis)
Mediterranean sage (Salvia aethiopsis)
Musk thistle (Carduus nutans)
Myrtle spurge (Euphorbia myrsinites)
Oxeye daisy (Chrysanthemum leucantheum)
Perennial pepperweed (Lepidium latifolium)
Plumeless thistle (Carduus acanthoides)
Poison hemlock (Conium maculatum)
Purple loosestrife (Lythrum salicaria)
Russian knapweed (Acroptilon repens)
Russian olive (Elaeagnus angustifolia)
Salt cedar (Tamarix parviflora, Tamarix ramosissima)
Scentless chamomile (Tripleurospermum perforatum)
Scotch thistle (Onopordum acanthium)
Spotted knapweed (Centaurea maculosa)
Sulfur cinquefoil (Potentilla recta)
Yellow starthistle (Centaurea solstitalis)
Yellow toadflax (Linaria vulgaris)
Spring Valley Ranch Weed Management Plan
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APPENDIX C - PHOTO DOCUMENTATION
PHOTO LOG
Project Name:Site Location:Date:
Photo Point 1 (P1)
Photo Point 2 (P2)
Nov 4, 2021Spring Valley Ranch Spring Valley Ranch
Noxious Weeds Survey
General vegetation overview
Common mullein, Cheatgrass,
Houndstongue.
PHOTO LOG
Project Name:Site Location:Date:
Photo Point 3 (P3)
Photo Point 4 (P4)
Nov 4, 2021Spring Valley Ranch Spring Valley Ranch
Noxious Weeds Survey
Ditch & pasture area
Pasture area with Canada thistle
PHOTO LOG
Project Name:Site Location:Date:
Photo Point 5 (P5)
Photo Point 6 (P6)
Nov 4, 2021Spring Valley Ranch Spring Valley Ranch
Noxious Weeds Survey
Canada thistle
Redstem storksbill
PHOTO LOG
Project Name:Site Location:Date:
Photo Point 7 (P7)
Photo Point 8 (P8)
Nov 4, 2021Spring Valley Ranch Spring Valley Ranch
Noxious Weeds Survey
Cheatgrass & other weeds
along two track roads
Houndstongue, highest density
observed.