HomeMy WebLinkAbout217 W. TRILBY ROAD SUBDIVISION - PDP - PDP120006 - REPORTS - ENVIRONMENTAL REPORTEcological Characterization Report
Affordable Roofing Property
City of Fort Collins
Larimer County, Colorado
prepared for:
Landmark Engineering Ltd.
3521 W. Eisenhower Blvd., Loveland, Colorado 80537
&
Affordable Roofing Inc.
50 East North Temple Street, 10th Floor, Salt Lake City, Utah 84150
prepared by:
Western Ecological Resource, Inc.
711 Walnut Street, Boulder, Colorado 80302
March 2013
Acknowledgement
Wildlife Sections prepared by:
Michael C. Figgs
Landscape, Resource, Ecosystem Planning Inc.
PO Box 5
Allenspark, CO 80501
Table of Contents
Section / Title Page
1.0 Introduction ........................................................................................................................... 1
2.0 Environmental Setting ............................................................................................................. 1
3.0 Methods ................................................................................................................................. 1
3.1 Vegetation .......................................................................................................................... 1
3.2 Wildlife .............................................................................................................................. 1
4.0 Vegetation Resources ............................................................................................................. 2
4.1 Agricultural Grassland ........................................................................................................ 2
4.2 Disturbed Weedy Habitat ................................................................................................... 2
4.3 Weedy Irrigation Ditch ....................................................................................................... 2
4.4 Ornamental Trees ............................................................................................................... 3
4.5 Federally Listed & Sensitive Species .................................................................................... 3
4.5.1 Federally Listed Plants .................................................................................................. 3
4.5.2 Sensitive Plants, Potential Conservation Areas, Natural Communities, & Natural Areas . 3
5.0 Wildlife Resources ................................................................................................................. 4
5.1 Wildlife Habitats................................................................................................................. 4
5.2 Special Habitats .................................................................................................................. 4
5.2.1 Raptor Habitat .............................................................................................................. 4
5.2.2 Concentration Areas for Nesting and Migratory Shorebirds and Waterfowl ................... 4
5.2.3 Migratory Songbird Concentration Areas ...................................................................... 4
5.2.4 Key Nesting Areas for Grassland Birds .......................................................................... 4
5.2.5 Fox and Coyote Dens ................................................................................................... 5
5.2.6 Mule Deer Concentration Area ..................................................................................... 5
5.2.7 Prairie Dog Colonies .................................................................................................... 5
5.2.8 Concentration Areas for Rare, Migrant, or Resident Butterflies ...................................... 5
5.2.9 Areas of High Terrestrial or Aquatic Insect Diversity ..................................................... 5
5.2.10 Irrigation Ditches that Serve as Wildlife Corridors ....................................................... 5
5.3 Federally Listed & Sensitive Wildlife Species ....................................................................... 5
5.3.1 Bald Eagle .................................................................................................................... 5
5.3.2 Ferruginous Hawk ........................................................................................................ 5
5.3.3 Yellow-Billed Cuckoo .................................................................................................. 6
5.3.4 Preble's Meadow Jumping Mouse ................................................................................ 6
5.3.5 Black-Tailed Prairie Dog ............................................................................................... 6
5.3.6 Swift Fox ...................................................................................................................... 6
5.3.7 Common Garter Snake ................................................................................................. 6
5.4 Records Search ................................................................................................................... 6
6.0 Proposed Development .......................................................................................................... 7
6.1 Details ................................................................................................................................ 7
7.0 Impacts .................................................................................................................................. 7
7.1 Vegetation .......................................................................................................................... 7
7.1.1 Vegetation Types.......................................................................................................... 7
7.1.2 Ornamental Trees ........................................................................................................ 7
7.1.3 Ditch Relocation & Design ........................................................................................... 7
7.1.4 Federally Listed, Sensitive Plants, Potential Conservation Areas, Natural Communities,
& Natural Areas .................................................................................................................... 7
7.2 Wildlife .............................................................................................................................. 7
8.0 Proposed Natural Area ........................................................................................................... 8
Table of Contents (continued)
Section / Title Page
9.0 Figures ................................................................................................................................... 9
10.0 Tables ................................................................................................................................ 15
11.0 Photos ................................................................................................................................ 24
12.0 References ........................................................................................................................ 27
List of Figures
Number / Title Page
Figure 1. Vicinity Map ............................................................................................................... 10
Figure 2. Project Location Map .................................................................................................. 11
Figure 3. Vegetation Type Map .................................................................................................. 12
Figure 4. Development Plan ...................................................................................................... 13
Figure 5. Concept Natural Areas Plan ........................................................................................ 14
List of Tables
Number / Title Page
Table 1. Plant Species List ......................................................................................................... 16
Table 2. Trees on Project Site .................................................................................................... 17
Table 3. Federally Listed Threatened, Endangered and Candidate Plants of Colorado ................. 18
Table 4. Federally & State Listed Threatened & Endangered Wildlife Species & State Listed
Species of Concern ............................................................................................................. 20
Table 5. Native Upland Prairie Seed Mix ................................................................................... 21
Table 6. Native Mixed-Grass Prairie/Wetland Seed Mix ............................................................. 22
Table 7. Native Woody Prairie Plantings ................................................................................... 23
List of Photos
Number / Title Page
Photo 1. Agricultural Grassland, looking north (01/15/13). ........................................................ 25
Photo 2. Large plains cottonwood, which likely exceeds 100 years in age (01/15/13). .............. 25
Photo 3. North Louden Ditch Lateral, looking north from south end of property (1/15/13). ........ 26
Photo 4. Existing office building (1/15/13). ................................................................................ 26
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1.0 Introduction
The Affordable Roofing Company Inc. has plans to develop their ~2.5 acre property located at
217 West Trilby Road in Fort Collins, Larimer County, Colorado (Figure 1). Specifically, the
property is located in the northeast quarter of Section 14 of Township 6 North and Range 69 West
(Figure 2). The existing property would be divided into four lots. The existing office building
would be incorporated into Lot 1 and each of the other three lots would have an office building.
In order to divide the property, the existing North Louden Ditch would be relocated.
Per the requirement of Fort Collins Land Use Code Division 3.4 Environmental, Natural Area,
Recreational and Cultural Resource Protection Standards, an Ecological Characterization Report
has been prepared to describe the natural habitats of the project site and assess the potential
impact of the development on the vegetation and wildlife resources of the property. A concept
plan for the creation of a Natural Area around the relocated ditch and detention ponds has been
developed to enhance the ecological value of the project site.
Please note, Figures are located in Section 9.0, Tables are in Section 10.0, and Photos are in
Section 11.0.
2.0 Environmental Setting
The Affordable Roofing property is located southwest of the intersection of West Trilby Road and
U.S. 287 (South College Avenue) (Figure 1). West Trilby Road forms the north boundary of the
property, which is surrounded by undeveloped land north of West Trilby Road and to the west.
Commercial areas occur to the immediate east, and there is a single family residence and
undeveloped land to the south. Single family residential neighborhoods occur further to the
south, west and northwest. The topography of the site slopes gently to the northeast from a high
of 5,069 feet to a low of 5,041. The North Louden Ditch extends across the project site for 560
linear feet. There are no streams or ponded water on the project site. However, the ditch has
been inactive for the past two years and weeds have colonized the bottom and sides of the ditch.
The property has an agricultural land use history and currently has a commercial business use.
There is one existing office building, two sheds, and a few shipping containers used for storage.
The past agricultural and the current commercial land uses have eliminated the native short grass
prairie which once characterized the project site.
3.0 Methods
3.1 Vegetation
The vegetation types and disturbed habitats of the project site were identified and described
during a site reconnaissance on January 15, 2013, and aerial photography was used to map the
location of these site features. All trees on the property were identified by species, and the height
and diameter-at-breast height (dbh) of each was ocularly estimated (Table 2).
Data from the U.S. Fish & Wildlife Service (2012), the Colorado Natural Heritage Program, and
site reconnaissance was used to determine the potential presence of federally listed and sensitive
plant species, as well as plant communities of importance.
3.2 Wildlife
Wildlife habitats were identified and described during a site visit on January 25, 2012. The
project site was inventoried to determine if any notable wildlife features, such as raptor nests and
fox and coyote dens were present. A second site visit was held on March 1, 2013 with Shane
Craig, Colorado Parks & Wildlife District Wildlife Manager.
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Projects documents were reviewed, as were applicable sections of the Fort Collins Land Use Code
and Natural Habitats & Features Inventory Map. Online data sources reviewed specifically
included the Natural Diversity Information Source (NDIS 2012), Colorado Natural Heritage
Program (2008) and Colorado Herptofaunal Atlas (2012).
4.0 Vegetation Resources
The project site is characterized by an agricultural grassland, a disturbed weedy habitat, a weedy
irrigation ditch, and ornamental tree plantings. A total of 21 species of plants were observed on
the project site, and 75% are non-native (Table 1). Seven plants are listed as Colorado noxious
weeds. Figure 3 and Photos 1 through 4 illustrate the vegetation resources of the project area.
Please note, almost half of the project site is disturbed and lacks any significant vegetative cover.
4.1 Agricultural Grassland
The 0.61 acre agricultural grassland, located east of the North Louden Ditch, is dominated by
smooth brome (Bromus inermis) with scattered weeds such as Canada thistle (Cirsium arvense)
and kochia (Bassia sieversiana). The grassland, which is mowed in the fall, was likely part of a
farming operation in the past.
4.2 Disturbed Weedy Habitat
The 0.77 acres of landscape west and northeast of the ditch is highly disturbed and characterized
by barren areas due to current commercial land uses, but also has populations of annual and
perennial weeds such as cheatgrass (Anisantha tectorum), kochia, prickly lettuce (Lactuca serriola),
and field bindweed (Convolvulus arvensis). See Table 1. In addition, these areas contain a
recycled asphalt parking area and small landscaping beds around the existing office building.
4.3 Weedy Irrigation Ditch
As illustrated by Figure 3, the North Louden Ditch extends north across the project site for 560
feet in an approximately 10 foot wide and four foot deep swale with steep banks. The bottom of
the ditch is dominated by lambs quarters (Chenopodium album) and kochia, both non-native
annual forb, and the sides of the ditch support other weedy species such as teasel (Dipsacus
fullonum), tumble mustard (Sisymbrium altissimum), common mullein (Verbascum thapsus),
prickly lettuce, hairy evening primrose (Oenothera villosa), and Canada thistle. Scattered small
patches of reed canarygrass (Phalaris arundinacea), an aggressive non-native wetland plant, are
present as well. There are no wetlands present.
The U.S. Army Corps of Engineers (Corps) has not yet determined the jurisdictional status of the
ditch, however it would not likely be considered jurisdictional by the Corps because it rarely has
irrigation flows. In fact, this ditch did not have any flows in 2011 and 2012. The ditch has one
downstream water user located north of West Trilby Road.
The ditch and its weedy vegetation have a very low ecological value. Specifically, the ditch
provides some groundwater recharge when it conveys irrigation water, which is rare, but has no
groundwater discharge or floodwater retention/peak flood reduction functions because it does not
convey stormwater flows. The vegetation provides a low value erosion protection and velocity
reduction functions for irrigation water when it flows. Likewise, the sediment removal and
nutrient retention/removal functions for irrigation flows are low to non-existent due to the short
duration of flow and the lack of any ponding to enable sediment and/or nutrients to settle out and
then be utilized by plants. Finally, the irrigation ditch and the adjacent weedy vegetation provide
a low value habitat for urban adapted birds and small mammals.
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4.4 Ornamental Trees
Both ornamental and native trees occur on the project site. See Figure 3 and Table 2. Six
ornamental trees occur along West Trilby Road, including five blue spruce (Picea pungens) and
one Norway maple (Acer platanoides). These trees range in height from 40 to 60 feet and have
dbh’s from 12 to 24 inches. In addition, a stand of six Rocky Mountain junipers (Juniperus
scopulorum) about 35 feet tall with dbh’s of 6 to 12 inches were planted along the North Louden
Ditch. Along the ditch there is also one large plains cottonwood which has a dbh estimated at ten
feet, a height of 80 feet and a crown diameter of approximately 100 feet. This tree likely
colonized the site over a hundred years ago when the site was actively farmed. There is one 20
foot tall apple tree (Malus domestica), a relic of the past farm, west of the ditch and west of the
office building, with a 12 inch dbh. At the southwest corner of the project site, several ponderosa
pine (Pinus ponderosa) occur on the property to the south. These trees were likely planted as a
visual screen.
4.5 Federally Listed & Sensitive Species
4.5.1 Federally Listed Plants
There are seven endangered, nine threatened, four candidate, and one proposed plants listed by
the U.S. Fish & Wildlife Service (2013) for the State of Colorado (Table 3). However, only the
Colorado butterfly plant (Gaura neomexicana ssp. coloradensis) and the Ute ladies' tresses orchid
(Spiranthes diluvialis) have a distribution in Larimer County. The western prairie fringed
orchid(Platanthera praeclara), a plant located downstream along the Platte River in Nebraska, is of
a concern, but only for those projects that result in water depletions to the Platte River system.
This project would not result in any water depletions.
The Colorado butterfly plant is a federally threatened, short-lived perennial herbaceous plant.
This subspecies occurs primarily on subirrigated alluvial soils on level or slightly sloping
floodplains and drainage bottoms at elevations between 5,000-6,400 feet (USFWS, 2000). The
butterfly plant requires early- to mid-successional riparian habitat, and colonies are often found in
low depressions or along bends in wide, active, meandering stream channels a short distance
upslope of the actual channel (USFWS, 2000). The Colorado butterfly plant appears to require
shallow subsurface water, and it is not found where streams are deeply incised (Rocky Mountain
Heritage Task Force, 1987). The project site does not provide appropriate habitat for the Colorado
butterfly plant.
The Ute ladies’ tresses orchid is a federally threatened perennial herbaceous plant endemic to
moist soils in mesic or wet meadows near springs, lakes, or perennial streams (USFWS, 1995;
Jennings, 1990). In Colorado, the elevational range of known Ute ladies’ tresses orchid
populations is between 4,500 and 6,800 feet (Spackman et al., 1997). This orchid prefers sites
with permanent sub-irrigation such as floodplains where the water table is near the surface
throughout the growing season and into the late summer or early autumn (USFWS, 1995;
Jennings, 1990). The project site does not provide appropriate habitat for the Ute ladies’ tresses
orchid.
4.5.2 Sensitive Plants, Potential Conservation Areas, Natural Communities, & Natural Areas
A records search for the vicinity of the project site was conducted of the online Colorado Natural
Heritage Program (CNHP) database for element occurrence records (EOR's) of threatened,
endangered and sensitive plant species and communities (CNHP 2008 & 2012). This database
was also checked for the presence of sites of biodiversity significance, known as Potential
Conservation Areas (PCA's), on or near the project site. No EORs for threatened, endangered and
sensitive plants or PCAs occur on or adjacent to the project site. EOR's for plants within a three
mile radius include Rocky Mountain sedge (Carex saximontana, G5/S1) and bell's twinpod
(Physaria bellii, G2/G2/S2S3). Nearby natural communities tracked by the CNHP include
Foothills Shrubland (Cercocarpus montanus - Hesperostipa neomexicana, G2G3/S2S3), Mountain
mahogany – Skunkbrush/Big Bluestem Shrubland (Cercocarpus montanus – Rhus trilobata/
4
Andropogon gerardii, G2G3/S2S3), and the Plains Cottonwood Riparian Woodland (Populus
deltoides/Carex pellita) ranked as G2/S1. None of these plants and plant communities, or any
other tracked by the CNHP occur on the project site.
Several City of Fort Collins Natural Areas occur in the region of the project site. The nearest City
of Fort Collins Natural Areas include the Prairie Dog Meadow Natural Area located about one-half
mile to the northeast, the Pelican Marsh Natural Area located one-half mile to the southeast and
the Hazaleus and Colina Mariposa Natural Areas located one-half mile to the west. These Natural
Areas are depicted on Figure 2.
5.0 Wildlife Resources
5.1 Wildlife Habitats
The project site’s commercial land uses have supplanted historical farming and ranching land
uses. As a result, no native wildlife habitat is present. The majority of the project site is disturbed,
with bare ground, graveled parking lots, structures, and materials storage areas (Photos 2-4). The
agricultural grassland has not been maintained, and has declined in quality and is characterized
by a reduced vegetation cover and weeds. The North Louden Ditch is weedy and has no riparian
habitat, and no permanent water source. No riparian or wetland habitats occur on the project site.
The wildlife habitat of note is the trees on the project site. A black-billed magpie nest was
observed in one of the Rocky Mountain junipers, and a red-tailed hawk was perching on the top
of the large plains cottonwood located immediately to the west of the existing office building.
The hawk was watching a prairie dog town on an adjacent property to the north across West
Trilby Road and was not disturbed by pedestrians or traffic passing immediately below the perch
site.
5.2 Special Habitats
The following special habitat features are addressed herein, per the Fort Collins Land Use Code.
5.2.1 Raptor Habitat
No stick nests were observed on or near the project site. Raptors can be expected to use the
larger trees as hunting perches, particularly the large plains cottonwood. The project site is
located within overall bald eagle winter range. Identified bald eagle habitat is located
approximately 0.75 mile to the north and 1.0 mile to the east of the project site along Fossil
Creek. None of the mapped habitats for this species, including winter concentration area, winter
forage, communal roost and summer forage, occur on the project site (NDIS 2012).
5.2.2 Concentration Areas for Nesting and Migratory Shorebirds and Waterfowl
There are no permanent water features or wetlands on the project site, and therefore no
concentration areas for waterfowl or shorebirds are present.
5.2.3 Migratory Songbird Concentration Areas
Migratory songbirds are expected to use the project site in spring and fall, utilizing primarily the
trees in the north-central area. There is no exceptional migratory habitat present, such as riparian
woodland with extensive wetlands that would attract concentrations of migrants. The areas with
trees tend to lack structural diversity, such as a well developed shrub understory and a wide range
of tree age classes.
5.2.4 Key Nesting Areas for Grassland Birds
There is no native prairie on the project site, and therefore key nesting areas for grassland birds are
not present.
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5.2.5 Fox and Coyote Dens
No coyote or fox dens were found during the site visits.
5.2.6 Mule Deer Concentration Area
According to NDIS (2012) the project site is not within a mapped concentration area or migration
corridor for mule deer. The project site also lacks the appropriate habitat, such as an abundance
of cover and browse.
5.2.7 Prairie Dog Colonies
No prairie dogs were observed on the project site. However, a small (approximately five acre)
prairie dog town is located on the property north of West Trilby Road, and a second town of less
than one acre is located to the south of the project site.
5.2.8 Concentration Areas for Rare, Migrant, or Resident Butterflies
Concentration areas for rare butterflies are typically determined by the presence of the suitable
host plants within appropriate habitats that are within the range of the specific butterfly species of
concern. No rare butterflies are expected on the project site, since there are no native vegetation
communities, no non-native stands of vegetation with a native grass/forb component, and no
wetlands with a native grass/forb component.
5.2.9 Areas of High Terrestrial or Aquatic Insect Diversity
Since there are no native stands of vegetation, or significant wetlands, no area of high insect
diversity is expected on the project site.
5.2.10 Irrigation Ditches that Serve as Wildlife Corridors
There is little vegetation along the North Louden Ditch except weeds. There are no shrubs and
few trees along the ditch to provide cover, a key element of a movement corridor. There are
structures and materials storage areas on either side of the ditch that also impair the ditch being
used as a movement corridor.
As discussed in Section 4.5.2, none of the City of Fort Collins Natural Areas occur near the project
site (Figure 2). Commercial land uses along College Avenue separate the Prairie Dog Meadow
and Pelican Marsh Natural Areas from the project site, and residential land uses along West Trilby
Road separate the Colina Mariposa and Hazaleus Natural Areas from the project site. The result is
that the project site cannot provide habitat buffers or significant connectivity in support of these
Natural Areas.
5.3 Federally Listed & Sensitive Wildlife Species
Table 4 lists federal and state listed endangered and threatened species, and State of Colorado
listed "Species of Special Concern" (CDOW 2012) for those wildlife species likely to occur in the
Fort Collins area and potentially found on the project site. These species are described below.
5.3.1 Bald Eagle
The project site is located within overall bald eagle winter range. Identified bald eagle habitat is
located approximately 0.75 mile to the north and 1.0 mile to the east of the project site along
Fossil Creek. None of the mapped habitats for this species, including winter concentration area,
winter forage, communal roost and summer forage, occur on the project site (NDIS 2012).
5.3.2 Ferruginous Hawk
Ferruginous hawks inhabit the eastern plains of Colorado in open, arid grasslands. This species
often hunts in prairie dog towns during the winter months (Andrews and Righter 1992, Kingery
1998). There is a low probability of occurrence on the project site, with occasional individuals
6
hunting on the prairie dog town on an adjacent property to the north for brief periods in winter.
The project site does not have breeding habitat for this species.
5.3.3 Yellow-Billed Cuckoo
The yellow-billed cuckoo inhabits dense riparian woodlands. This species nests in shrubs and
trees within the riparian canopy, and is known to nest in the Front Range area (Andrews and
Righter 1992, Kingery 1998). There is a very low probability of occurrence on the project site as
there is no appropriate riparian woodland habitat, and the tree stands present do not have well
developed shrub understories.
5.3.4 Preble's Meadow Jumping Mouse
The project site is within the overall range of Preble's meadow jumping mouse (NDIS 2012). The
mouse inhabits riparian shrublands on the plains and lower foothills (Fitzgerald et al. 1994). The
U.S. Fish and Wildlife Service did not identify the project site to be within the species critical
habitat (USFWS 2012). The project site does not have the appropriate riparian, wetland and
floodplain habitat required by this species.
5.3.5 Black-Tailed Prairie Dog
Black-tailed prairie dogs form large colonies on the shortgrass prairie and agricultural land on the
plains of Larimer County, but there are no colonies on the project site. A small colony of
approximately five acres is located on an adjacent property north of West Trilby Road.
5.3.6 Swift Fox
The swift fox inhabits and breeds on vast expanses of shortgrass prairie, including eastern Larimer
County (Fitzgerald et al. 1994, NDIS 2012). In the past, Colorado populations have been greatly
reduced by hunting, trapping, and poisoning. Due to the absence of natural prairie habitat on the
project site and in the neighborhood, there is a very low probability of occurrence on the project
site.
5.3.7 Common Garter Snake
The common garter snake is generally restricted to aquatic, wetland, and riparian habitat and is
seldom found away from water (Hammerson 1999). It remains common within portions of its
range and declining in other areas due in part to loss of habitat in the Front Range Urban Corridor.
The Colorado Herptofaunal Atlas (2012) has records in the Fossil Creek Reservoir area. The
probability of this species occurring on the project site is low as the appropriate aquatic, wetland
and riparian habitat is not present.
5.4 Records Search
A records search for the vicinity of the project site was conducted of the online Colorado Natural
Heritage Program (CNHP) database for element occurrence records (EOR's) for threatened,
endangered and sensitive wildlife species (Colorado Natural Heritage Program 2008 and 2012).
Nearby EOR's included documentation for the bald eagle and black-tailed prairie dog. As
discussed above, the project site does not include habitat for the bald eagle, waterfowl, or
shorebirds.
This database was also checked for the presence of PCA's on or near the project site. Fossil Creek
Reservoir, located east of the project site, is included in the South Platte River PCA. This PCA
includes most of the South Platte River in northeastern Colorado and associated large reservoirs.
The PCA is justified primarily by multiple occurrences of the bald eagle, and secondarily on
waterfowl and shorebird populations. See Section 4.5.2.
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6.0 Proposed Development
6.1 Details
As illustrated by Figure 4, the 2.5 acre project site would be subdivided into four lots ranging in
size from 0.32 to 1.22 acres. The existing office building would remain and be incorporated into
Lot 1. Lots 2, 3 and 4 would each contain an office building and associated garage and outdoor
parking. Lots 1, 2 and 3 would be accessed via a new road from West Trilby Road. Lot 4 would
be accessed via a new road along the west property line. Stormwater from the development
would be directed into stormwater quality detention ponds which would drain to the Ditch. Two
ponds would be located west of the ditch and four would be located east of the ditch. All of the
ponds would discharge to the ditch. In addition, a six foot wide sidewalk would be constructed
along West Trilby Road. The North Louden Ditch would be realigned across the project site. The
property entry and exit points for the Ditch would not be changed, however a portion of the Ditch
would be moved up to 48 feet to the west and a 60 foot long segment of the Ditch on the north
end would be piped. The Ditch would have a 6 foot wide bottom and side slopes of 4:1, and be
within a 70 foot wide easement.
7.0 Impacts
7.1 Vegetation
7.1.1 Vegetation Types
Developments would likely eliminate all of the agricultural grassland and most of the disturbed
weedy habitats on the project site.
7.1.2 Ornamental Trees
Thirteen of the trees on the project site would remain and be incorporated into the landscape
plan, and one tree would be removed. A blue spruce approximately 40 feet tall with a 12 inch
dbh would be removed in order to provide road access to Lots 1, 2, and 3.
7.1.3 Ditch Relocation & Design
Development of the project site would require the relocation of the irrigation ditch. As illustrated
by Figure 4, the North Louden Ditch would be moved up to 40 feet to the west. The new ditch
would be 70 feet wide and have side slopes of 4:1 with a relatively flat bottom. The reconstructed
swale would drain to the north with a 1-2% slope. The ditch would have the capacity to deliver
irrigation water to the land owner north of West Trilby Road when needed, and would also
convey stormwater runoff from on-site detention ponds to the north.
7.1.4 Federally Listed, Sensitive Plants, Potential Conservation Areas, Natural Communities,
& Natural Areas
The project would not impact federally listed and sensitive plant species, CNHP listed Natural
Communities, or City of Fort Collins Natural Areas because none occur on the project site.
7.2 Wildlife
All native habitat on the project site has been impacted and/or removed, and remaining wildlife
species are adapted to an urban setting. The only wildlife feature of note on the project site is the
mature trees located in the north-central area, particularly the large plains cottonwood (Photos 1,
2 and 4). Only one of the existing 14 trees, a blue spruce, will be removed. Project wildlife
impacts are therefore projected to be minimal and insignificant. The project would not impact
federally listed species, sensitive species or CNHP listed wildlife resources because none occur on
the project site. The proposed natural area described below will restore native habitat to a
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significant portion of the project site. Although the project site will remain within a highly
fragmented habitat landscape, the on-site habitat will be greatly improved over current conditions.
8.0 Proposed Natural Area
The proposed Natural Area would encompass the 70 foot wide and 560 foot long relocated North
Louden Ditch easement and extend outward to incorporate three detention ponds (Figure 5). This
Natural Area will be characterized by a native prairie composed of plants common to the plains
ecosystem of eastern Colorado. The bottom of the ditch would have stormwater flows from
detention ponds on the property. An above ground temporary irrigation system would be
provided to water the herbaceous seeding and shrub plantings and a permanent drip irrigation
system would be provided for the trees.
The side slopes of the ditch and detention ponds would be seeded with the native prairie seed
mix of Table 5. This seed mix is characterized by seven grasses and seven forbs common to the
shortgrass prairie. The more moist bottom of the ditch and detention ponds would be seeded with
the seed mix of Table 6. This seed mix contains native tallgrass species, plants common to moist
wetlands, and attractive flowering native forbs.
Approximately 150 shrubs of seven different species would be planted in small monoculture
stands composed of 7-8 shrubs throughout the Natural Area on the banks of the ditch and around
the detention ponds. Shrubs to plant include rubber rabbitbrush (Chrysothamnus nauseosus),
American plum (Prunus americanus), chokecherry (Prunus virginiana ssp. melanocarpa),
skunkbrush sumac (Rhus trilobata), wax currant (Ribes cereum), Wood’s rose (Rosa woodsii), and
yucca (Yucca glauca). A total of 30 trees would be planted along the ditch and around the
detention ponds. They include 10 smoothbark cottonwood (Populus x acuminate) and 20 plains
cottonwood Populus deltoides). See Table 7. Please note, a Landscape Plan will be prepared to
illustrate the locations of the seedings and wooding plantings.
The native seedings and plantings of the Natural Area and the adjacent detention ponds would
create a native plant community with a high ecological value. The native communities would
stabilize the soil and prevent wind and water erosion, and create a native wildlife habitat with a
high plant species diversity and with structural diversity. These communities would provide food
and cover for wildlife and the detention ponds would provide a temporary source of water. The
detention ponds would reduce peak stormwater flows and the ponds and the bottom of the ditch
would result in groundwater recharge.
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9.0 Figures
Legend
Property Boundary
Existing Office Building
Figure 1. Vicinity Map
Affordable Roofing Property
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Western Ecological Resource Inc.
711 Walnut Street
Boulder, CO 80302
303-449-9009
²
Background: 2009 Bing Maps Aerial
1 inch = 5,000 feet
Scale:000 1:60,
10
LONG VIEW FARM
HAZALEUS NATURAL AREA
PELICAN MARSH NATURAL AREA
COLINA MARIPOSA NATURAL AREA
PRAIRIE DOG MEADOW NATURAL AREA
COYOTE RIDGE NATURAL AREA
CATHY FROMME PRAIRIE NATURAL AREA
REDTAIL GROVE NATURAL AREA
TWO CREEKS NATURAL AREA
Legend
Property Boundary
Natural Areas
Figure 2. Project Location Map
Affordable Roofing Property
Western Ecological Resource Inc.
711 Walnut Street
Boulder, CO 80302
303-449-9009
²
1 inch = 2,000 feet
BASE: USGS 7.5' Ft. Collins & Loveland, Colorado Quadrangles
Scale:000 1:24,
Property Boundary
COLORADO
Map Location
11
Figure 3. Vegetation Type Map
Affordable Roofing Property
Legend
Property Boundary
North Louden Ditch
Vegetation Types
Agricultural Grassland
Weedy Irrigation Lateral
Disturbed Weedy Habitat
Background: 2009 Bing Maps Aerial
1 inch = 75 feet
±
Scale:900 1:
Agricultural
Grassland
Disturbed Weedy Habitat
Ponderosa Pines (offsite)
Blue Spruces &
Norway Maple
Weedy Irrigation Lateral
Rocky Mountain Junipers
Existing Office Building
Apple Tree Plains Cottonwood
West Trilby Road
12
13
14
15
10.0 Tables
16
Table 1. Plant Species List
TABLE 1
Plant Species List
Affordable Roofing Property
Scientific Name Common Name Family Origin
Trees
Acer platanoides Norway maple Aceraceae I
Juniperus scopulorum Rocky Mountain Juniper Cupressaceae N
Malus domestica Apple tree Rosaceae I
Picea pungens Blue spruce Pinaceae N
Populus deltoides Plains cottonwood Salicaceae N
Perennial Graminoids
Bromus inermis Smooth brome Poaceae I
Phalaris arundinacea Reed canarygrass Poaceae I
Perennial Forbs
Cirsium arvense (Breea) Canada thistle Asteraceae I+
Convolvulus arvensis Field bindweed Convolvulaceae I+
Potentilla recta Sulphur cinquefoil Rosaceae I+
Rumex crispus Curly dock Polygonaceae I
Symphyotrichum ascendens (Virgulaster) Longleaved aster Asteraceae N
Annual/Biennial Forbs
Bassia sieversiana (Kochia scoparia) Kochia Chenopodiaceae I
Carduus nutans ssp. macrolepis Musk thistle Asteraceae I+
Chenopodium album Lambs quarters Chenopodiaceae I
Dipsacus fullonum (D. sylvestris) Common Teasel Dipsacaceae I+
Lactuca serriola Prickly lettuce Asteraceae I
Oenothera villosa Hairy evening primrose Onagraceae N
Sisymbrium altissimum Tumble mustard Brassicaceae I
Verbascum thapsus Common mullein Scrophulariaceae I+
Annual Graminoids
Anisantha tectorum (Bromus) Cheatgrass; Downy brome Poaceae I+
Plants observed during site reconnaissance in January 2013.
* N = Native, I = Introduced, I+ = Colorado Noxious Weed
17
Table 2. Trees on Project Site
TABLE 2
Trees on Project Site
Affordable Roofing Property
Scientific Name
Common Name
No. of
Trees
Approx.
DBH
Approx.
Height
Notes
Acer platanoides Norway maple 1 22” 50’ Ornamental
Juniperus scopulorum Rocky Mountain Juniper 6 Ornamental, planted along ditch
Juniper 1 12” 35’
Juniper 2 6” 35’
Juniper 3 12” 35’
Juniper 4 8” 35’
Juniper 5 10” 35’
Juniper 6 12” & 8” 35’ Two trunks
Malus domestica Apple tree 1 12” 20’ Ornamental
Picea pungens Blue spruce 5 Ornamental, planted along W. Trilby Road
Spruce 1 12” 40’
Spruce 2 22” 40’
Spruce 3 24” 55’
Spruce 4 24” 58’
Spruce 5 12” 40’ Only tree to be removed for development
Populus deltoides Plains cottonwood 1 10’ x 6’ 80’ Huge, three-trunked native
18
Table 3. Federally Listed Threatened, Endangered and Candidate Plants of Colorado
TABLE 3
Federally Listed Threatened, Endangered and Candidate Plants of Colorado
Page 1 of 2
Scientific Name
Common Name
Federal
Status
Colorado
Distribution
Habitat
Astragalus humillimus Mancos milkvetch Endangered Montezuma Rock ledges in pinyon-juniper woodland, 5,500-
5,850 ft.
Astragalus microcymbus Skiff milkvetch Candidate Gunnison, Saguache Open, park-like landscapes in sagebrush shrubland on
rocky or cobbly, moderate to steep slopes of hills and
draws, 7,600-8,400 ft.
Astragalus osterhoutii Osterhout milkvetch Endangered Grand Seleniferous clay soils in big sagebrush shrubland,
7,400-7,900 ft.
Astragalus schmolliae Schmoll milkvetch Candidate Montezuma Mature pinyon-juniper woodlands, 6,800 - 7,000 ft.
Astragalus tortipes Sleeping Ute milk-vetch Candidate Montezuma Desert scrub -Mancos shale, 5,400-5,700 ft.
Eriogonum pelinophilum Clayloving wild buckwheat Endangered Delta, Montrose Mancos shale badlands in saltbrush shrubland, 5,200 -
6,400 ft.
Eutrema penlandii Penland alpine fen mustard Threatened Park, Summit Moist calcareous alpine habitats, 12,300 - 13,100 ft.
Gaura neomexicana
ssp. coloradensis
Colorado butterfly plant Threatened Boulder, Broomfield,
Douglas, Jefferson,
Larimer, Weld
Sub-irrigated, alluvial soils of drainage bottoms, 5,800-
6,200 ft.
Ipomopsis polyantha Pagosa skyrocket Endangered Archuleta Pagosa-Winifred soils derived fom Mancos shale,
6,800-7,200 ft.
Lesquerella congesta Dudley bluffs bladderpod Threatened Rio Blanco Barren, white shale outcrops of the Green River and
Uinta Formations, 6,000-6,700 ft.
Pediocactus knowltonii Knowlton cactus Endangered La Plata Alluvial deposits in pinyon-juniper and big sagebrush,
6,400 ft.
Penstemon grahamii Graham beardtongue Proposed
Threatened
Rio Blanco Calcareous soils derived from oil shale barrens of the
Green River Formation. Sparsely vegetated pinyon-
juniper and desert shrub communities, 4,690-6,760 ft.
Penstemon debilis Parachute beardtongue Threatened Garfield
Oil shale outcrops, on south-facing, steep white shale
talus on the Mahogany Zone of the Parachute Creek
Member of the Green River Formation, 8,000-9,000 ft.
Penstemon penlandii Penland beardtongue Endangered Grand Barrens -Troublesome Formation, 7,500 -7,700 ft.
19
TABLE 3
Federally Listed Threatened, Endangered and Candidate Plants of Colorado
Page 2 of 2
Scientific Name
Common Name
Federal
Status
Colorado
Distribution
Habitat
Penstemon scariosus
albifluvis
White River beardtongue Candidate Rio Blanco Mixed desert shrub, pinyon-juniper, in shales of Green
River Formation, 5,000-7,200 ft.
Phacelia formosula North Park phacelia Endangered Jackson, Larimer Barrens-sandstone outcrops Coalmont Formation,
8,000-8,500 ft.
Phacelia submutica DeBeque phacelia Threatened Garfield, Mesa Sparsely vegetated steep slopes in clay of Wasatch
Formation, 4,700-6,200 ft.
Physaria obcordata Dudley Bluffs twinpod Threatened Rio Blanco Barrens -Green River Formation, 5,900 -7,500 ft.
Sclerocactus glaucus Colorado hookless cactus Threatened Delta, Garfield,
Mesa, Montrose
Desert shrub, 4,500-6,000 ft.
Sclerocactus mesae-verdae Mesa Verde cactus Threatened Montezuma Shale or adobe clay badlands, 4,000-5,000 ft.
Spiranthes diluvialis Ute ladies' tresses orchid Threatened Adams, Arapahoe,
Boulder, Broomfield,
Denver, Douglas,
Eagle, El Paso,
Garfield, Jefferson,
Larimer, Moffat,
Morgan, Pitkin, Weld
Sub-irrigated, alluvial soils along streams, 4,500-
6,800 ft.
Source: U.S. Fish & Wildlife Service website. www. fws.gov. List current as of January 15, 2013
20
Table 4. Federally & State Listed Threatened & Endangered Wildlife Species & State Listed Species of Concern
TABLE 4
Federally & State Listed Endangered & Threatened Wildlife Species
& State Listed Species of Concern
Common Name Scientific Name Status*
Birds
Bald Eagle Haliaeetus leucocephalus SC
Ferruginous Hawk Buteo regalis SC
Yellow-billed Cuckoo Coccyzus americanus SC
Burrowing Owl Athene cunicularia ST
Mammals
Preble’s Meadow Jumping
Mouse
Zapus hudsonius preblei FT/ST
Black-tailed Prairie Dog Cynomys ludovicianus SC
Swift Fox Vulpes velox SC
Reptiles
Common garter snake Thamnophis sirtalis SC
*Status Codes:
FE = Federally Endangered
FT = Federally Threatened
SE = State Endangered
ST = State Threatened
SC = State Special Concern (not a statutory category)
21
Table 5. Native Upland Prairie Seed Mix
TABLE 5
Native Prairie Seed Mix
Affordable Roofing Property
Seeding Rate
Scientific Name (var.) Common Name PLS Lbs./acre*
Grasses
Aristida purpurea Purple three-awn 1/2
Buchloe dactyloides Buffalograss 2
Chondrosum gracile Blue grama 1
Elymus elymoides Squirreltail 1
Elymus trachycaulus (San Luis) Slender wheatgrass 6
Pascopyrum smithii (Arriba) Western wheatgrass 6
Stipa comata Needle and thread 1
Subtotal 17 1/2
Forbs
Artemisia frigida Fringed sage 1/16
Coreopsis tinctoria Plains coreopsis 1/16
Gaillardia pulchella Blanket flower 1/2
Liatris punctata Dotted gayfeather 1/2
Penstemon angustifolius Narrowleaf penstemon 1/2
Ratibida columnifera Prairie coneflower 1/8
Sphaeralcea coccinea Scarlet globemallow 1/4
Subtotal 2
TOTAL 19 1/2
* Drill seed rate. Double application for broadcast methods.
22
Table 6. Native Mixed-Grass Prairie/Wetland Seed Mix
TABLE 6
Native Mixed-Grass Prairie/Wetland Seed Mix
Affordable Roofing Property
Seeding Rate
Scientific Name Common Name PLS Lbs./acre*
Graminoids
Andropogon gerardii Big bluestem 2
Elymus canadensis Canada wildrye 2
Glyceria striata Fowl mannagrass 2
Juncus balticus Baltic rush 1/8
Panicum virgatum Switchgrass 3
Pascopyrum smithii Western wheatgrass 4
Poa palustris Fowl bluegrass 1/8
Scirpus paludosus Alkali bulrush 2
Sorghastrum nutans Indiangrass 2
Subtotal 17 1/4
Forbs
Asclepias speciosa Showy milkweed 1
Helianthus nuttallii Marsh sunflower 1/2
Solidago canadensis Canada goldenrod 1/8
Subtotal 1 5/8
TOTAL 18 7/8
* Drill seed rate. Double application for broadcast methods.
23
Table 7. Native Woody Prairie Plantings
TABLE 7
Native Woody Prairie Plantings
Affordable Roofing Property
Scientific Name
Common Name
Wetland
Status*
Size
No. to
Plant
Trees
Populus x. acuminata Smoothbark cottonwood FAC 1" caliper 5
Populus deltoides Plains cottonwood FAC 1" caliper 10
Subtotal 15
Shrubs
Chrysothamnus nauseosus Rubber rabbitbrush NL 5-gallon 10
Prunus americana American plum FACU 5-gallon 10
Prunus virginiana
ssp. melanocarpa
Chokecherry FACU 5-gallon 10
Rhus trilobata Skunkbrush sumac NL 5-gallon 10
Ribes cereum Wax currant NL 5-gallon 10
Rosa woodsii Woods rose FACU 5-gallon 10
Yucca glauca Yucca NL 5-gallon 10
Subtotal 70
TOTAL 85
*Wetland Status (2012 Great Plains List)
OBL = Obligate Wetland
FACW = Facultative Wetland
FAC = Facultative
FACU = Facultative Upland
UPL = Obligate Upland
NL = Not Listed (not a wetland plant)
24
11.0 Photos
25
Photo 1. Agricultural Grassland, looking north (01/15/13).
Photo 2. Large plains cottonwood, which likely exceeds 100 years in age (01/15/13).
26
Photo 3. North Louden Ditch, looking north from south end of property (1/15/13).
Photo 4. Existing office building (1/15/13).
27
12.0 References
Andrews, Robert and Robert Righter. 1992. Colorado Birds. A Reference to Their Distribution and
Habitat. Denver Museum of Natural History.
Colorado Division of Wildlife. 2012. Colorado Listing of Endangered, Threatened, and Wildlife
Species of Concern [Online]. Available:
http://wildlife.state.co.us/WildlifeSpecies/SpeciesOfConcern/ThreatenedEndangeredList/Pages/Li
stOfThreatenedAndEndangeredSpecies.aspx [Last accessed October 15, 2012].
Colorado Herpetofaunal Atlas. 2012. [Online]. Available:
http://ndis.nrel.colostate.edu/herpatlas/coherpatlasD/viewer.htm [Last accessed October 15,
2012]. Colorado State University, Fort Collins, Colorado, U.S.A.
Colorado Natural Heritage Program. 2012. Biodiversity Tracking and Conservation System. Colorado
State University, Fort Collins, Colorado, U.S.A. Tracked Vascular Plant Species. [Online].
Available: http://www.cnhp.colostate.edu/tracking/vascular.html [Last accessed March 28,
2012].
Colorado Natural Heritage Program. 2008. State-wide Potential Conservation Areas and State-wide
Elements by Quad (August 2008), Arc View Shapefiles. [Online]. Available:
http://www.cnhp.colostate.edu/gis.html [Last accessed March 28, 2012].
Fitzgerald, James P, and Carron A. Meaney and David M. Armstrong. 1994. Mammals of Colorado.
Denver Museum of Natural History and University Press of Colorado.
Hammerson, Geoffrey A. 1999. Amphibians and Reptiles in Colorado. Second Edition. University
Press of Colorado and Colorado Division of Wildlife.
Jennings, William F. 1990. Final Report. Species studied: Spiranthes diluvialis, Sisyrinchium
pallidum. Report for the Nature Conservancy under the Colorado Natural History Small Grants
Program. The Nature Conservancy, Boulder, Colorado.
Kingery, Hugh E. (Ed.). 1998. Colorado Breeding Bird Atlas. Colorado Bird Atlas Partnership.
Natural Diversity Information Source (NDIS). 2012. Colorado Division of Wildlife. Wildlife Species
Page [Online]. Available: http://ndis.nrel.colostate.edu/wildlife.asp [Last accessed October 15,
2012].
Rocky Mountain Heritage Task Force. 1987. Field inventory and demographic studies of the Colorado
butterfly plant (Gaura neomexicana ssp. coloradensis) in Nebraska, Colorado, and Wyoming.
The Nature Conservancy, Denver.
Spackman, S., et al. 1997. Colorado Rare Plant Field Guide. Prepared for the Bureau of Land
Management, the U.S. Forest Service, and the U.S. Fish and Wildlife Service by the Colorado
Natural Heritage Program.
US Fish & Wildlife Service. 2012. Preble's Meadow Jumping Mouse Critical Habitat. [Online].
Available: http://www.fws.gov/mountain-prairie/species/mammals/preble/CRITICAL
HABITAT/CRITICALHABITATindex.htm [Last accessed October 15, 2012].
U.S. Fish and Wildlife Service. 2000. Endangered and threatened wildlife and plants: Threatened
status for the Colorado butterfly plant (Gaura neomexicana ssp. coloradensis) from southeastern
Wyoming, Northcentral Colorado, and extreme western Nebraska, Final Rule.
U. S. Fish and Wildlife Service. 1995. Ute Ladies'-tresses (Spiranthes diluvialis) recovery plan. U.S.
Fish and Wildlife Service, Denver, Colorado.