HomeMy WebLinkAbout1.33 Weed Mgmnt PlanLake Springs Ranch
Subdivision Preliminary Plan/PUD Amendment December 2025
Exhibit 33 | Weed Management Plan
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Prepared for:
TGMC, LLC
402 Park Drive
Glenwood Springs, CO 81601
Prepared by:
RedMountain Environmental, LLC.
802 Palmer Avenue
Glenwood Springs, CO 81601
970-309-5190
November 29, 2023
Noxious Weed Management Plan
Lake Springs Ranch
Garfield County, Colorado
Lake Springs Ranch Weed Management Plan
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Table of Contents
1.0 Summary ............................................................................................................................. 1
2.0 Project Description .............................................................................................................. 1
3.0 Description of Survey Area .................................................................................................. 2
4.0 Results of Surveys ................................................................................................................ 5
5.0 Noxious Weed Management Recommendations ................................................................ 7
List of Tables
Table 1 – Noxious Weeds Present on Property ............................................................................................ 1
List of Figures
Figure 1 – Project Vicinity ............................................................................................................................. 3
Figure 2 – Proposed Development ............................................................................................................... 4
Figure 3 – Noxious Weed Occurrences ......................................................................................................... 6
Appendices
Appendix A – Colorado Listed Noxious Weeds
Appendix B – Garfield County Listed Noxious Weeds
Appendix C - Photo Documentation
Lake Springs Ranch Weed Management Plan
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1.0 SUMMARY
This Weed Management Plan was prepared at the request of TGMC, LLC. and Longhorn Opportunity Fund
#1, to fulfill the submittal requirements of the Land Use and Development Code (LUDC) for an amendment
to the preliminary plan approval for the Lake Springs Ranch development (Project). Lake Springs Ranch is
proposing to develop 84 single family lots and 8 multi-family lots on the approximately 203-acre property
for residential use. The Project is located in Garfield County, Colorado in Sections 33 and 34, Township 6
South, Range 88 West, and Section 4, Township 7 South, Range 88 West (6th Principal Meridian) (Figure 1).
RME was retained to conduct a noxious weed survey on behalf of TGMC, LLC to fulfill requirements of
Garfield County’s LUDC. A field survey documenting and mapping noxious weeds was conducted in the fall
of 2023 in support of this report.
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
2.0 PROJECT DESCRIPTION
The property is a 203.7-acre parcel located in the Spring Valley area southwest of Glenwood Springs. The
area is approximately 3.8 miles from State Highway 82 on County Road 114 (CMC Road). The proposed
project includes the development of residential lots as well as protection of 77.87-acres of open space (or
38 percent of the Project area (Figure 2).
Noxious Weeds
Common Name Scientific Name Colorado Listed
Species
Garfield County
Listed Species
Canada thistle Cirsium arvense Yes (List B) Yes
Common tansy Tanacetum vulgare Yes (List B) Yes
Hoary cress/ whitetop Cardaria draba Yes (List B) Yes
Houndstongue Cynoglossum officinale Yes (List B) Yes
Plumeless thistle Carduus acanthoides Yes (List B) Yes
Russian knapweed Acroptilon repens Yes (List B) Yes
Cheatgrass Bromus [Anisantha] tectorum Yes (List C) No
Common mullein Verbascum thapsus Yes (List C) No
Field bindweed Convolvulus arvensis Yes (List C) No
Redstem filaree Erodium cicutarium Yest (List C) No
Curly dock Rumex crispus No Yes
Lake Springs Ranch Weed Management Plan
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3.0 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 a mixed shrub component comprised 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) with an understory of crested wheatgrass
(Agropyron cristatum) and native forbs and grasses. The portion of the property immediately adjacent to
ponds support wetland vegetation. No wetlands extend beyond the immediate boundaries of the ponds,
and no development is planned to occur in wetland areas.
Typical conditions in mixed mountain shrublands at
the base of steep slopes. Typical conditions in pasture areas.
Typical conditions of wetland areas around ponds. Typical conditions of sagebrush shrublands.
Lake Springs Ranch Weed Management Plan
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Figure 1 – Project Vicinity
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Figure 2 – Proposed Development
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4.0 RESULTS OF SURVEYS
The most common noxious weeds found within the project area, in descending concentrations, include:
cheatgrass, hoary cress/whitetop, Russian knapweed, Scotch thistle, Canada thistle, plumeless thistle,
field bindweed, common mullein, common tansy, houndstongue, and redstem filaree. Areas that have
been used as local access roads, areas around previous vegetation disturbance features, and pasture areas
around the ponds (Figure 3) were noted for having a high to very high concentration of weeds, particularly
hoary cress, Russian knapweed, and Scotch thistle. Hoary cress is present in low to medium densities
throughout the pasture areas and appears to be spreading from areas of high concentrations. Curly dock
was observed in the fringe of wetland vegetation around the ponds. Figure 3 shows the areas of noxious
weed infestations, relative densities/percent cover, and acreage of infestation. It is possible that other
noxious weed species exist within the property but were not visible within the tall pasture grass during
the time of the site visit. Appendix C is a photo log documenting the noxious weed presence and densities
throughout the project area.
Lake Springs Ranch Weed Management Plan
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Figure 3 – Noxious Weed Occurrences
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5.0 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 (at this time there are no List A species on the property);
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.
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.
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APPENDIX A – COLORADO LISTED NOXIOUS WEEDS
Colorado Noxious Weeds (including Watch List)
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)
Lake Springs Ranch Weed Management Plan
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Hoary cress (Cardaria draba)
Houndstongue (Cynoglossum officinale)
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)
Lake Springs Ranch Weed Management Plan
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)
Lake Springs Ranch Weed Management Plan
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)
Lake Springs Ranch Weed Management Plan
APPENDIX C – PHOTO LOG
PHOTO LOG
Project Name: Site Location: Date:
Photo Point 1 (P1)
Photo Point 2 (P2)
Aug 8, 2023Lake Springs RanchLake Springs
Scotch thistle along access road
Access road
PHOTO LOG
Project Name: Site Location: Date:
Photo Point 3 (P3)
Photo Point 4 (P4)
Aug 8, 2023Lake Springs RanchLake Springs
Native thistle
Plumeless thistle in previously
disturbed vegetation (east side
of property in strip)
PHOTO LOG
Project Name: Site Location: Date:
Photo Point 5 (P5)
Photo Point 6 (P6)
Aug 8, 2023Lake Springs RanchLake Springs
Canada thistle
Scotch thistle under oak
PHOTO LOG
Project Name: Site Location: Date:
Photo Point 7 (P7)
Photo Point 8 (P8)
Aug 8, 2023Lake Springs RanchLake Springs
Russian knapweed along access
road
Russsian knapweed and Scotch
thistle along access road above
pond
PHOTO LOG
Project Name: Site Location: Date:
Photo Point 9 (P9)
Photo Point 10 (P10)
Aug 8, 2023Lake Springs RanchLake Springs
High cover Scotch thistle area
Whitetop, Russian knapweed
along pond/pasture areas
PHOTO LOG
Project Name: Site Location: Date:
Photo Point 11 (P11)
Photo Point 12 (P12)
Aug 8, 2023Lake Springs RanchLake Springs
Whitetop, Scotch thistle,
Russian knapweed along pond/
pasture areas
Russian knapweed in pasture
area
PHOTO LOG
Project Name: Site Location: Date:
Photo Point 13 (P13)
Photo Point 14 (P14)
Aug 8, 2023Lake Springs RanchLake Springs
Very high cover of Whitetop,
Russian knapweed, Scotch
thistle
Common tansy