VEGETATION TYPE MAP, COMMUNITY DESCRIPTIONS & FLORISTIC INVENTORY

North Star Nature Preserve June 2019 Pitkin County,

Prepared for: Pitkin County Open Space and Trails 530 East Main Street, Suite 201 Aspen, CO 81611

Prepared by: Peak Ecological Services, LLC 301 Boulder Canyon Drive, PO Box 827 Nederland, Colorado 80466

VEGETATION TYPE MAP, COMMUNITY DESCRIPTIONS & FLORISTIC INVENTORY North Star Nature Preserve Pitkin County, Colorado

revision date: June 12, 2019

Summary This report maps and qualitatively describes the vegetation types on the North Star Nature Preserve in order to provide baseline information for management. Each vegetation type is also classified to U.S. National Vegetation Classification (USNC) standards. Finally, an updated vascular species list for the property is provided and the floristic quality index is calculated.

TABLE OF CONTENTS

1.0 INTRODUCTION ...... 1 2.0 METHODS ...... 1 3.0 RESULTS ...... 1 3.1. Vegetation Classification & Mapping ...... 1 3.1.1 Aspen Forest ...... 2 3.1.2 Douglas Forest ...... 3 3.1.3 Narrowleaf Cottonwood Riparian Forest ...... 3 3.1.4 Blue- Forest ...... 5 3.1.5 Gambel Oak Shrubland ...... 5 3.1.6 Mountain Big Sagebrush – Sticky Rabbitbrush Shrubland ...... 6 3.1.7 Mountain Wet Shrubland ...... 6 3.1.8 Shrubby Cinquefoil Wet Shrubland ...... 7 3.1.9 Smooth Brome Ruderal Grassland ...... 7 3.1.10 Beaked Sedge Wet Meadow ...... 8 3.1.11 Reed Canarygrass Ruderal Marsh ...... 8 3.1.12 Wet Meadow (Meadows Foxtail Ruderal Marsh and Clustered Field Sedge Wet Meadow) ...... 9 3.2 Floristics...... 11 3.2.1 Floristic Inventory ...... 11 3.2.2 Floristic Quality Assessment ...... 11 4.0 REFERENCES ...... 12 5.0 FIGURES ...... 13 APPENDIX A. PLANT SPECIES LIST ...... 15

LIST OF TABLES Table 1. Vegetation Types. North Star Nature Preserve...... 10 Table 2. Floristic Quality Assessment Results. North Star Nature Preserve...... 11

LIST OF FIGURES Figure 1. Vegetation Type Map ...... 14

June 2019 – Vegetation Community Descriptions and Floristic Inventory – North Star Nature Preserve Page i

LIST OF PHOTOS Photo 1. Young Aspen Forest along trail (Aug-08-2018)...... 2 Photo 2. Douglas Fir Forest (Aug-08-2018)...... 3 Photo 3. Narrowleaf cottonwoods along Roaring Fork River (Sep-25-2017)...... 3 Photo 4. Sinuous channel of the Roaring Fork River through North Star circa 1900...... 4 Photo 5. Narrowleaf Cottonwood - Willow Riparian Habitat along intermittent stream (Sep-25-2017)...... 4 Photo 6. Planted Blue Spruce (Sep-22-2018)...... 5 Photo 7. Sagebrush and Sticky Rabbitbrush Shrubland (Aug-8-2018)...... 6 Photo 8. Mountain Willow Wet Shrubland (Sep-25-2017)...... 6 Photo 9. Non-Native Smooth Brome Grassland (Aug-08-2018)...... 7 Photo 10. Beaked Sedge Wetland Association (Jul-12-2017)...... 8 Photo 11. Reed Canarygrass (Jul-28-2017)...... 8 Photo 12. Patches of Wet Meadow intermixed in the drier upland non-native Smooth Brome Grassland...... 9

June 2019 – Vegetation Community Descriptions and Floristic Inventory – North Star Nature Preserve Page ii 1.0 INTRODUCTION

The North Star Nature Preserve (175-acres) and the adjacent James H. Smith Open Space (70+ acres) are unique and valuable tracts of open space on the edge of Aspen – an ecological sanctuary that encompasses significant wetland and riparian ecological communities and wildlife habitat (PCOST 2015). These properties, collectively called the North Star Nature Preserve (North Star), encompass a flat bottomland bisected by the Roaring Fork River and bounded by steep mountainsides. North Star supports both xeric and mesic plant communities influenced by abiotic factors such as moisture, elevation, aspect, and geology, but also by past land management which has included grazing, farming, and irrigation.

Some of the original riparian and wetland habitat on North Star was drained and were eliminated in order to grow agricultural grasses in the 1950’s. However, there are still areas of high-quality wetlands on North Star, including an herbaceous fen located at the northwest corner and a willow wetland beaver pond complex along the southern boundary of North Star. Other vegetation types present include narrowleaf cottonwood (Populus angustifolia) riparian forest, aspen (Populus tremuloides) forests, blue spruce (Picea pungens) stands, mountain big sagebrush (Artemisia tridentata ssp. vaseyana) shrublands, and an open meadow dominated by a mosaic of agricultural upland and mesic grasslands. On the steep hillsides on the west side of the Reserve are Douglas fir (Pseudotsuga menziesii) forests and Gambel oak (Quercus gambelii) shrublands.

The purpose of this study was to map and qualitatively describe the vegetation types on North Star to provide baseline information for the management of the vegetation resources. In addition, an updated inventory was conducted.

2.0 METHODS Prior to field reconnaissance, a preliminary vegetation type map was generated based on high quality aerial imagery, existing 2-foot and 1-foot contours, existing studies, and past field reconnaissance. Field verification of the preliminary mapping was completed by Rea Orthner and Denise Wilson on August 8, September 21- 22, and October 24, 2018. During the pedestrian surveys, representative data points were taken, the names of the dominant taxa and their abundance ranking by vegetation stratum was recorded, and presence of noxious weeds was noted. Each data point was also accompanied by representative photograph(s). Based on field reconnaissance, the preliminary vegetation map was revised to incorporate the results. All vegetation mapped was also classified to the U.S. National Vegetation Classification (USNVC) standards (USNVC 2017).

3.0 RESULTS

3.1. VEGETATION CLASSIFICATION & MAPPING The U.S. National Vegetation Classification (USNVC) is a central organizing framework for documentation, inventory, monitoring, and study of vegetation in the from broad scale formations like forests to fine-scale plant communities. The vegetation communities at North Star were classified to the two most detailed or “lowest” levels of the classification hierarchy, alliances and associations. Alliances are classified based on diagnostic species, including some from the dominant growth form or layer, and are moderately similar in composition. Associations, which are more ”fine-grained,” are based on diagnostic species, usually from multiple growth forms or layers, and more narrowly similar. Mapping to the association level allows land managers to better track occurrences of specific plant communities, some of which may be rare or uncommon. See Table 1 at the end of this section for a list of the alliances and associations present at North Star. Overall, 14 different alliances and 15 plant associations were documented for North Star. The following text describes these vegetation communities based on field reconnaissance conducted in 2017 and 2018. First forested plant communities are described, next shrublands, and finally community types.

June 2019 – Vegetation Community Descriptions and Floristic Inventory – North Star Nature Preserve Page 1 3.1.1 ASPEN FOREST

Well-developed aspen forests occur west of the Roaring Fork river on gentle slopes above the valley floor. Stands of aspen are also present along the bike path east of the River. The aspen forests appear to best fit the Populus tremuloides / Amelanchier alnifolia – Symphoricarpos oreophilus / Thalictrum fendleri Forest Association, which is a low- to moderate-elevation aspen forest association that occurs in the central and southern Rocky Mountains west into northeastern (USNVC 2017). The dominant overstory tree is quaking aspen (Populus tremuloides), with a healthy native shrub understory comprised of snowberry Photo 1. Young Aspen Forest along trail (Aug-08-2018). (Symphoricarpos rotundifolius), serviceberry (Amelanchier alnifolia), chokecherry (Prunus virginiana), and grape (Mahonia repens). Mountain maple (Acer negundo) is also occasionally present. The herbaceous layer is represented by a variety of native and non-native perennial graminoids. Natives include blue wildrye (Elymus glaucus) and Letterman needlegrass (Achnatherum lettermanii), and non-natives include orchard grass (Dactylis glomerata), Kentucky bluegrass (Poa pratensis), timothy (Phleum pratense), and in moister areas redtop (Agrostis gigantea) occurs. Common native forbs include Fendler meadowrue (Thalictrum fendleri), aspen fleabane ( speciosus), western sweet cicely (Osmorhiza occidentalis), and yarrow (Achillea lanulosa). Non-native noxious weeds are also present including houndstongue (Cynoglossum officinale), yellow toadflax (Linaria vulgaris), and plumeless thistle (Carduus acanthoides). No rare or unique were identified within these forests. The Aspen Global Change Institute (AGCI) has established a permanent Modified-Whittaker vegetation plot in this plant community which was last monitored by the author in 2017 (PeakEco 2018b). The vegetation plot is part of AGCI’s Interactive Roaring Fork Observatory Network (iRON) climate stations. Overall, the aspen forests appear to be heavily browsed by wildlife. While some aspen stands appear to have healthy stock of regenerating young sprouts, other stands appear more decadent. Young stands of aspen occur east of the Roaring Fork River along the trail. Here the aspen contains an understory of serviceberry and whitestem gooseberry ( inerme) with mainly non-native graminoids such as orchardgrass (Dactylis glomerata) and reed canarygrass (Phalaris arundinacea). Some smooth blue (Symphyotrichum laeve) and field horsetail (Equisetum arvense) are present as well.

According to the USNVC (2017), this community is ranked as globally secure (G5).

June 2019 – Vegetation Community Descriptions and Floristic Inventory – North Star Nature Preserve Page 2 3.1.2 DOUGLAS FIR FOREST

Douglas fir forests occur intermixed with Gambel oak shrublands on the steep east-facing slopes above the valley floor. The understory is well represented by native shrubs such as Gambel oak, serviceberry, snowberry, and chokecherry, and subshrubs such as Oregon grape and whortleberry (Vaccinium myrtillus). Herbaceous species include elk sedge ( geyeri) along with Fendler meadowrue (Thalictrum fendleri), Engelmann’s aster (), bedstraw (Galium boreale), and bluntseed sweet cicely (Osmorhiza depauperata). These forests belong to the Douglas Fir / Gambel Oak Association which occurs in southern Photo 2. Douglas Fir Forest (Aug-08-2018). Rocky Mountains and southwestern U.S. and is found on foothills, mountains and plateaus from Colorado to Trans-Pecos , west to and . It is ranked as Globally secure (G5) by the USNVC (2017). A few scattered toadflax plants, a noxious weed, were observed in this plant association as well. This forest type appears to be stable and no insect outbreaks or diseases were noted.

3.1.3 NARROWLEAF COTTONWOOD RIPARIAN FOREST There are scattered narrowleaf cottonwood (Populus angustifolia) stands along the entire reach of the Roaring Fork River through North Star as well as along two intermittent drainages on the hillsides west of the river. Those stands on the valley floor belong to the Narrowleaf Cottonwood / Invasive Perennial Grass Ruderal Riparian Woodland and are characterized by a moderately open to closed (50-90% cover) tree canopy dominated by Populus angustifolia, with an understory dominated by introduced perennial grasses without a notable shrub layer (USNVC, 2017). At North Star, these small forested areas typically support a dense grassy understory comprised of non-native pasture grasses such as meadow foxtail (Alopecurus pratensis), smooth brome ( inermis), Kentucky bluegrass, redtop, and reed canarygrass. Native graminoids, when present, include Baltic rush (Juncus balticus), fowl bluegrass (Poa palustris), and Bebb’s sedge (Carex bebbii). Forbs sporadically encountered include leafy bracted aster (Symphyotrichum foliaceum) and King’s Photo 3. Narrowleaf cottonwoods along Roaring Fork River (Sep-25- ragwort (Senecio eremophilus kingii). 2017).

June 2019 – Vegetation Community Descriptions and Floristic Inventory – North Star Nature Preserve Page 3 There is one permanent vegetation quantitative data transect located in the Narrowleaf Cottonwood / Invasive Perennial Grass Association (PeakEco 2018a). This riparian association occurs in the foothill and lower montane zones of the Rocky Mountains extending west into the Great Basin and east onto the northern plains. This “ruderal” vegetation type it is not ranked because of the dominance of non- native plants in the understory. Narrowleaf cottonwood were probably not extensive on North Star in pre-settlement times, as evidenced by historical photography which shows the wide valley Photo 4. Sinuous channel of the Roaring Fork River through North Star circa 1900 (Aspen dominated by willows. Historical Society). Furthermore, North Star is at the upper elevational limit at which narrowleaf cottonwoods can successfully establish and grow. The relic stands present today have a variable size (diameter), height and age structure, which illustrates several past periods of successful reproduction. A cursory assessment of the narrowleaf cottonwood saplings at North Star on the valley floor indicate that while there are numerous young sprouts, they are heavily browsed. However, it is not known whether these young sprouts represent clonal (asexual reproduction) from existing trees or successful sexual reproduction from seed. Land management activities at North Star should include strategies that support the reproductive ecology of these native trees to ensure long-term persistence.

Cottonwood forests also occur along two intermittent drainages on the hillsides to the west of the valley floor. These areas are classified as the Narrowleaf Cottonwood – Mountain Willow Riparian Forest. These narrow riparian corridors contain a mix of narrowleaf cottonwood, with scattered aspen and occasional blue spruce. The understory supports mountain willow (Salix monticola), Woods’ rose (Rosa woodsii), as well as elk sedge. This plant association is known from the Colorado Plateau, the San Juan Mountains, and the Great Basin areas of Colorado, Utah and Nevada, and is ranked as Globally Vulnerable (G3) according to the USNCV (2017). Photo 5. Narrowleaf Cottonwood - Willow Riparian Habitat along intermittent stream (Sep-25-2017).

June 2019 – Vegetation Community Descriptions and Floristic Inventory – North Star Nature Preserve Page 4 3.1.4 BLUE-SPRUCE FOREST

Several stands of blue spruce occur throughout North Star and some stands appear to have been planted, while others appear to be the result of successful natural reproduction such as those that occur amidst the wet willow shrublands. These areas belong to the Blue Spruce Southern Rocky Mountain Mesic Forest Alliance. Those stands on the valley bottom appear to best fit the Blue Spruce / Twinberry Honeysuckle Association which is ranked as globally imperiled (G2), however there is some uncertainty in assigning to this association by the author. This is a riparian forest association, characterized by a mixture of deciduous and evergreen trees in the Photo 6. Planted Blue Spruce (Sep-22-2018). canopy including blue spruce, narrowleaf cottonwood, and some aspen. The shrub layer is comprised of species such as twinberry honeysuckle (Lonicera involucrata), serviceberry, whitestem gooseberry, Woods’ rose, and snowberry. Several species of willows may also be common in more mesic areas. The herbaceous layer is dominated by mesic-site perennial forbs, including starry false Solomon’s seal (Maianthemum stellatum), field horsetail (Equisetum arvense), and cow parsnip (Heracleum maximum).

In addition, there are two areas of a Blue Spruce - Aspen Association at North Star on the hillsides to the west of the valley floor. This successional, mixed aspen-conifer forest occurs in the montane forest zone in Colorado and Utah from 7,400-9,100 feet in elevation. This association represents the successional stage where blue spruce has converted the formerly deciduous canopy dominated by aspen to a mixed conifer-deciduous canopy. The understory is comprised of a tall shrub layer of mountain maple (Acer glabrum), serviceberry, and Woods’ rose. Elk sedge is a common graminoid. This association is ranked as G3G4, or globally vulnerable to globally apparently secure by the USNVC (2017). Overall, the two blue spruce forest associations at North Star appear to be healthy and free of disease.

3.1.5 GAMBEL OAK SHRUBLAND Gambel oak shrubland is intermixed with Douglas fir forest on the steep east facing slopes above the valley floor. The vegetation is classified as the Gambel Oak / Mountain Snowberry Shrubland Association and is found in foothills, plateaus and mountains from western Texas to southern and western Colorado. The vegetation is characterized by an open to closed shrub layer dominated by Gambel oak. The understory is composed of a short-shrub layer that is dominated by snowberry. Other shrubs present include serviceberry, chokecherry, Woods’ rose, and the subshrub whortleberry. Common herbaceous species include elk sedge, bedstraw, and mountain parsley (Cymopterus lemmonii). Non-natives such as orchardgrass and Kentucky bluegrass are also present. This association is ranked as globally secure (G5) by the USNVC (2017).

June 2019 – Vegetation Community Descriptions and Floristic Inventory – North Star Nature Preserve Page 5 3.1.6 MOUNTAIN BIG SAGEBRUSH – STICKY RABBITBRUSH SHRUBLAND

A mixed mountain big sagebrush and sticky rabbitbrush (Chrysothamnus viscidiflorus) shrubland occurs between the aspen, Douglas fir, and Gambel oak communities and the low-lying grasslands. This shrubland belongs to the Mountain Big Sagebrush – Mixed Steppe and Shrubland Alliance which is widespread in the mountainous areas across the western U.S. No association is currently described for the co-dominance of these two shrub species. The vegetation is characterized by a moderate to dense shrub layer in which Artemisia tridentata subsp. vaseyana is Photo 7. Sagebrush and Sticky Rabbitbrush Shrubland (Aug-8-2018). codominant with sticky rabbitbrush. At North Star, Letterman’s needlegrass (Achnatherum lettermanii) is the dominant perennial graminoid. Less abundant perennial graminoids include Kentucky bluegrass, smooth brome and orchardgrass, which are all non-native, as well as a few natives such as slender wheatgrass (Elymus trachycaulus) and needle-and-thread grass (Hesperostipa comata). Baltic rush (Juncus arcticus subsp. ater) occurs in more mesic areas. These areas support perennial forbs such as aspen fleabane, Rocky Mountain penstemon (Penstemon strictus), lupine (Lupinus argenteus), yarrow (Achillea lanulosa), and wild tarragon (Oligosporus dracunculus subsp. glaucus). Noxious weeds include plumeless thistle, houndstongue, and mullein (Verbascum thapsus). These mixed sagebrush – rabbitbrush stands at North Star appear to have been impacted by past agricultural activities such as grazing or perhaps even fire. The high cover of sticky rabbitbrush, which is tolerant to grazing and also resprouts after fire, as well as the numerous non-native pasture grasses, are an indication of past impacts. This community may be a good target for restoration involving additional planting or seeding of mountain big sagebrush.

3.1.7 MOUNTAIN WILLOW WET SHRUBLAND The willow shrublands at North Star used to be far more extensive during presettlement times. Most of the shrublands on the valley floor were converted to hay pasture by former owners to promote production of forage for livestock. The willow shrublands that exist today are most well developed in the southern portion of North Star, but also flank the Roaring Fork River and are found adjacent to most of the low-lying oxbow wetlands. These remaining shrublands contain a significant Photo 8. Mountain Willow Wet Shrubland (Sep-25-2017).

June 2019 – Vegetation Community Descriptions and Floristic Inventory – North Star Nature Preserve Page 6 amount of non-native pasture grasses, but mesic native wetland graminoids and forbs do occur. These shrublands belong to the Mountain Willow / Mesic Graminoids Wet Shrubland Association which is ranked as Globally Vulnerable (G3) by the USNVC (2017). This association is known only from Colorado and , but may occur in the mountains of New and Utah. This shrubland association is characterized by a 5 to 8 foot tall, moderately open to dense, deciduous willow canopy with an herbaceous understory that is typically dominated by mixed mesic graminoids. The most common willows are mountain willow (Salix monticola) and Geyer willow (Salix geyeriana), with some whiplash willow (Salix lasiandra var. caudata) and alder (Alnus incana) as well. There are also one or two stands dominated by sandbar willow, also known as coyote willow (Salix exigua). The dominant perennial graminoids are non-native pasture species such as meadow foxtail, reed canarygrass and redtop. However, native grasses and sedges still do occur in certain locations. These include common species such as water sedge (Carex aquatilis), beaked sedge (Carex utriculata), bluejoint reedgrass (Calamagrostis canadensis), and fowl bluegrass (Poa palustris). Non- graminoid species include field horsetail, a fern ally, and largeleaf avens (Geum macrophyllum), starry false Solomon’s seal (Maianthemum stellatum), and white checkermallow (Sidalcea candida), which are all native forbs.

3.1.8 SHRUBBY CINQUEFOIL WET SHRUBLAND Two small areas dominated by shrubby cinquefoil ( fruticosa) occur at North Star. These areas belong to the Shrubby Cinquefoil Wet Shrubland Association which is found throughout the western montane U.S and and is ranked as globally secure (G5, USNVC 2017). This alliance is characterized by an open shrub layer of shrubby cinquefoil with Baltic rush, Kentucky bluegrass, as well as needle-and-thread grass. Canada thistle (Cirsium arvense), a noxious weed, occurs sporadically. According to the USNVC (2017), most stands of this association appear to be grazing-induced. Shrubby cinquefoil increases in abundance with continuous season-long grazing. Hence, the herbaceous species tend to be dominated by increaser species and non-native species including Kentucky bluegrass and Baltic rush, such as found at North Star.

3.1.9 SMOOTH BROME RUDERAL GRASSLAND An upland non-native grassland occurs throughout the North Star valley floor. Smooth brome has been widely planted for revegetating disturbed land as well as for pasture and hayfields. The dominant grass is Bromus inermis, a naturalized species from Eurasia that forms moderately dense to dense stands that often develop into monocultures. Other non-native grasses may also occur such as timothy, crested wheatgrass (Agropyron cristatum), quack grass (Elytrigia repens), and Kentucky bluegrass. Native species are generally less than 10% cover. These natives may include scattered sticky rabbitbrush shrubs and sporadic native forbs such as Rocky Mountain penstemon, aspen fleabane and yarrow. Noxious weeds are common, but are currently being controlled by Pitkin County Open Space and Trails. These include plumeless thistle, mullein and toadflax. According to data provided by the USNVC (2017) website, Bromus inermis is a strongly rhizomatous, cool- season grass that grows 1.5 – 3 feet tall. It is a highly competitive, sod-forming grass with a dense fibrous root and system. The extensive rhizome system Photo 9. Non-Native Smooth Brome Grassland (Aug-08-2018). allows it to rapidly spread and makes it able to tolerate

June 2019 – Vegetation Community Descriptions and Floristic Inventory – North Star Nature Preserve Page 7 heavy grazing by livestock (Hansen et al. 1995). Although this grass grows best on moist alluvial sites, it does not tolerate prolonged flooding (Hansen et al. 1995). It also has good drought resistance, which allows it to persist in semi-arid regions. Smooth brome is also fire-adapted and will vigorously sprout after most burns; however, this cool-season grass is not tolerant of hot, late-spring burns, which is during its active growing period (Hansen et al. 1995). This may be an effective control measure where native vegetation is dominated by warm-season grasses. This vegetation type belongs to the Smooth Brome Ruderal Grassland Association. Because the association is non-native, there is no ranking for it.

3.1.10 BEAKED SEDGE WET MEADOW This herbaceous wetland type occurs in low-lying swales throughout North Star and the old-growth wetland fen at the northwest corner of the meadow at North Star. It is classified as the Beaked Sedge (or northwest territory sedge) Wet Meadow Association, which is found throughout much of the western U.S. Is it ranked as globally secure (G5) by the USNVC (2017). This association is characterized by a clear dominance of beaked sedge, however minor amounts of water sedge may be also present. Other species present include panicled bulrush (Scirpus microcarpus), bog yellowcress (Rorripa palustris), arrowleaf groundsel (Senecio triangularis), and Photo 10. Beaked Sedge Wetland Association (Jul-12-2017). purple avens (Geum rivale).

Carex utriculata is a widespread species that colonizes recently formed pond edges and seasonally flooded areas near streams. Once established it is long-lived and will dominate sites unless disturbed with changes in site hydrology. At North Star, reed canarygrass and meadow foxtail, which are both non-native pasture grasses, are often intermixed into this vegetation type and may be co-dominant in some locations. This appears to be the result of a long-term drying effect to these wetland areas due to the trans-basin diversion, historic drainage ditches and other rangeland “improvements” implemented by previous land owners.

3.1.11 REED CANARYGRASS RUDERAL MARSH The Reed Canarygrass Ruderal Marsh contains little else but this invasive grass species which forms dense stands that are often six feet tall. It occurs throughout North Star in the flat valley bottom. Not only does reed canarygrass form dense monocultures where little else grows, it also occurs as small stands in the other riparian and wetland communities such as in

Photo 11. Reed Canarygrass (Jul-28-2017).

June 2019 – Vegetation Community Descriptions and Floristic Inventory – North Star Nature Preserve Page 8 the understory of cottonwoods and willows, mixed with beaked sedge wetland meadows, and has invaded the edges of the wetland fen.

This herbaceous association is reported from , Colorado, Nebraska, , , and into northeastern Utah, but is likely more widespread in the . It also occurs in Canada, in the southern two-thirds of in areas with warm and relatively dry summers and in Alberta, from the Great Plains north into the Boreal Plains. Its distribution as a natural type is complicated because this “native species” is widely cultivated as a forage crop and has escaped and established in wetlands and riparian areas, displacing the local flora (USNVC, 2017). Phalaris arundinacea is a threat to riparian and wetland areas because it spreads rapidly from , dominating sites, and is extremely difficult to remove once established. In Colorado, it is thought that most Colorado populations are the Eurasian ecotype and not the native type (Culver and Lemly, 2013).

3.1.12 WET MEADOW (CLUSTERED FIELD SEDGE WET MEADOW AND MEADOW FOXTAIL RUDERAL MARSH)

Two plant associations occur in the Wet Meadow vegetation type of North Star. Both of these associations are intermixed on the valley floor and thus are mapped together as one unit on the Vegetation Type Map and associated GIS files.

The Clustered Field Sedge Wet Meadow Association occurs in swales and along stream channels in the prairies of several western states (Montana, Idaho, Wyoming, Colorado, Utah, and Arizona) and on both sides of the Continental Divide. This association is ranked as G3G4 or globally vulnerable / globally apparently secure due to the wide Photo 12. Patches of Wet Meadow (dark green) intermixed in the drier upland non-native distribution as its apparent abundance Smooth Brome Grassland (Aug-8-2018). in several states (USNVC 20117). At North Star, this association commonly contains not only clustered field sedge (Carex praegracilis), but also Baltic rush, with its distinctive dark green appearance. Other species commonly present include timothy, dandelion (Taraxacum officinale) and salsify (Tragopogon dubius). Noxious weeds such as Canada thistle and plumeless thistle also occur.

The Meadow Foxtail Ruderal Marsh Association is seasonally moist to wet meadow, including flood-irrigated hay meadow, on floodplain flats and depressions. Alopecurus pratensis is an exotic, invasive grass that is an extremely important forage species throughout the region (USNVC 2017). At North Star, these meadows also support occasional plants of Baltic rush, beaked sedge, reed canarygrass, white checkermallow, smooth brome and redtop, but meadow foxtail always remains dominant. Similarity in landform position and species composition suggests that Alopecurus pratensis has successfully invaded and replaced phases of the Clustered Field Sedge Wet Meadow. When compared to the more diverse Carex praegracilis association, the lower species diversity of the Alopecurus pratensis Association may result from its competitive superiority over many of the species of the former community that were simply crowded out. It remains to be seen if its formidable competitive abilities will enable it to overwhelm other wet meadow vegetation types. This non-native plant

June 2019 – Vegetation Community Descriptions and Floristic Inventory – North Star Nature Preserve Page 9 association is not ranked by the USNVC (2017). Finally, these wet meadows may be a good location for future restoration of the wet willow shrubland vegetation types.

TABLE 1. VEGETATION TYPES. NORTH STAR NATURE PRESERVE. General Vegetation Type Detailed Vegetation Type Acres % of Area USNVC Alliance USNVC Association Aspen Forest Populus tremuloides / Amelanchier 18.59 7.5% A2036 alnifolia - Symphoricarpos oreophilus / Thalictrum fendleri Forest CEGL000569 Douglas Fir Forest Pseudotsuga menziesii / Quercus 10.76 4.4% A3454 gambelii Forest CEGL000452 Narrowleaf Cottonwood - Mountain Populus angustifolia / Salix 2.50 1.0% Willow Riparian Forest A3759 monticola Riparian Woodland CEGL002645 Narrowleaf Cottonwood Ruderal Riparian Populus angustifolia / Invasive 5.15 2.1% Forest A4155 Perennial Grasses Ruderal Riparian Woodland CEGL003749 Blue Spruce Mesic Forest Populus tremuloides - Picea pungens 2.48 1.0% A0165 Forest CEGL000535 Picea pungens / Lonicera 2.65 1.1% involucrata Forest CEGL000394 Gambel Oak – Snowberry Shrubland Quercus gambelii - Symphoricarpos 8.24 3.3% A3735 rotundifolius Shrubland CEGL001117 Mountain Big Sagebrush / Sticky Not yet described 8.22 3.3% Rabbitbrush Shrubland A3208 Mountain Willow Wet Shrubland Salix monticola Mesic Graminoids 46.60 18.8% A0981 Wet Shrubland CEGL002659 Shrubby Cinquefoil Wet Shrubland Dasiphora fruticosa ssp. 0.31 0.1% A0958 floribunda Wet Shrubland CEGL001105 Beaked Sedge Wetlands Carex utriculata Wet Meadow 9.98 4.0% A3804 CEGL001562 Smooth Brome Ruderal Grassland Bromus inermis Ruderal Grassland 58.17 23.5% A3254 CEGL005264 Reed Canarygrass Ruderal Marsh Phalaris arundinacea Western Marsh 28.99 11.7% A3846 CEGL001474 Wet Meadow Foxtail Ruderal Wet Alopecurus pratensis Western 32.66 13.2% Meadow A3847 Ruderal Wet Meadow CEGL005209 Clustered Field Sedge Wet Meadow Carex praegracilis Wet Meadow A3806 CEGL002660

June 2019 – Vegetation Community Descriptions and Floristic Inventory – North Star Nature Preserve Page 10 TABLE 1. VEGETATION TYPES. NORTH STAR NATURE PRESERVE. General Vegetation Type Detailed Vegetation Type Acres % of Area USNVC Alliance USNVC Association Water n/a 11.97 4.8% Grand Total 247.26 100.0% USNVC [United States National Vegetation Classification]. 2017. United States National Vegetation Classification Database, V2.01. Federal Geographic Data Committee, Vegetation Subcommittee, Washington DC.

3.2 FLORISTICS

3.2.1 FLORISTIC INVENTORY The following floristic inventory is based on work conducted in 2017 and updated in 2018. A total of 192 vascular plant species were observed during field reconnaissance. These include five species of trees, 27 shrubs/subshrubs, 45 perennial graminoids, 95 perennial forbs, one fern ally, 18 annual/biennial forbs, and 1 annual graminoid. Of the total, 36, or 19% are non-native and nine species are Colorado State listed noxious weeds. No rare plants tracked by the Colorado Natural Heritage Program were observed. However, there is one relatively uncommon plant, the slender spire orchid (Piperia unalascensis), which occurs in the southwestern portion of North Star (PeakEco 2018c). A vascular plant list is found in Appendix A.

3.2.2 FLORISTIC QUALITY ASSESSMENT The Floristic Quality Assessment (FQA) is a standardized method used to determine the ecological condition of a site in terms of its native floristic quality. It is a useful tool for assessing how human disturbances have affected plant community composition and for tracking changes in plant communities over time.

The FQA method is based on the concept of species conservatism. In general, species conservatism is a measure of how sensitive a species is to disturbance, and the degree of fidelity it has to a particular habitat or environment. This is represented by the C-value, or Coefficient of Conservatism, an integer ranging from 0-10 that has been assigned for a given geographic area. Species with low C-values are highly tolerant to disturbance and exhibit little fidelity to natural areas, and they may be found virtually anywhere. Non-native species have a rank of 0. In contrast, species with high C-values are highly intolerant to disturbance and are located in high-quality natural sites indicative of conditions prior to human settlement. The slender spire orchid, for example, has a C-value of 10 (the highest).

To assess the floristic quality within North Star Nature Preserve, two floristic quality measures were calculated including the mean C-values of all species and the mean C of native plants. The results (Table 2) show relatively low Mean C values of 4.5 (all species) and 5.6 (native species only), which are not unexpected given that North Star has a high number of non-native species and species widely tolerant of human disturbance.

TABLE 2. FLORISTIC QUALITY ASSESSMENT RESULTS. NORTH STAR NATURE PRESERVE.

Metric Mean C-Value Number of Species Mean C (All Species) 4.5 192 Mean C (Native Species) 5.6 156

June 2019 – Vegetation Community Descriptions and Floristic Inventory – North Star Nature Preserve Page 11 4.0 REFERENCES

Cronquist, A., A. H. Holmgren, N. H. Holmgren, J. L. Reveal, and P. K. Holmgren. 1977. Intermountain flora: Vascular plants of the Intermountain West, U.S.A. Volume 6: The . Columbia University Press, New York. 584 pp.

Culver, D. and J. Lemly. 2013. Field Guide to Colorado's Wetlands Plants. Identification, Ecology, and Conservation. Colorado State University, Colorado Natural Heritage Program.

Hansen, P. L., R. D. Pfister, K. Boggs, B. J. Cook, J. Joy, and D. K. Hinckley. 1995. Classification and management of Montana's riparian and wetland sites. Miscellaneous Publication No. 54. Montana Forest and Conservation Experiment Station, School of Forestry, University of Montana. 646 pp. plus posters

PCOST. 2015. North Star Nature Preserve Management Plan. Prepared by Pitkin County Open Space and Trails. 122 pp. PeakEco. 2018a. Technical Memorandum. 2017 Vegetation Monitoring. North Star Nature Preserve., Prepared by Peak Ecologial Services, LLC of Nederland, CO. Prepared for Pitkin County Open Space and Trails of Aspen, CO. February 2018. PeakEco. 2018b. Technical Memorandum. iRON 2017 Vegetation Monitoring, Brush Creek, North Star Transition, North Star Aspen, and Smuggler Mixed Conifer. Prepared by Peak Ecologial Services, LLC of Nederland, CO. Prepared for Aspen Center Global Change Institute (AGCI). February 2018. PeakEco. 2018c. Wetland Fen Assessment & Floristic Inventory. North Star Nature Preserve. Pitkin County, Colorado. Prepared by Peak Ecological Services, LLC of Nederland, CO. Prepared for Pitkin County Open Space and Trails, Aspen, CO. Dated February 2018. USNVC. 2017. United States National Vegetation Classification Database, V2.01. Federal Geographic Data Committee, Vegetation Subcommittee, Washington DC. [usnvc.org] accessed 14 January 2018.

June 2019 – Vegetation Community Descriptions and Floristic Inventory – North Star Nature Preserve Page 12

5.0 FIGURES

June 2019 – Vegetation Community Descriptions and Floristic Inventory – North Star Nature Preserve Page 13 US HWY 82

Figure 1. Vegetation Type Map Legend Aspen Forest Douglas Fir Forest Blue Spruce Forest Blue Spruce - Aspen Forest Aspen - Blue Spruce Forest Narrowleaf Cottonwood Native Forest Narrowleaf Cottonwood Non-Native Forest Gambel Oak Shrubland Sagebrush / Sticky Rabbitbrush Shrubland Mountain Willow Wet Shrubland Shrubby Cinquefoil Wet Shrubland Ü Smooth Brome Ruderal Grassland Scale: 1:4,800 1 inch = 400 feet Beaked Sedge Wetland Contour Interval = 10 ft Reed Canarygrass Ruderal Marsh Wet Meadow Water

June 2019 – Vegetation Community Descriptions and Floristic Inventory – North Star Nature Preserve Page 14 APPENDIX A. PLANT SPECIES LIST

June 2019 – Vegetation Community Descriptions and Floristic Inventory – North Star Nature Preserve Page 15 North Star Nature Preserve ‐ 2018 Vascular Plant Species List

Scientific Name Common Name Family Origin C‐ Voucher Value Photo

Trees Picea pungens Blue sprucePinaceae N 6 Pinus contorta var. latifolia Lodgepole pinePinaceae N 5 Populus angustifolia Narrowleaf cottonwoodSalicaceae N 5 Populus tremuloides Quaking aspenSalicaceae N 5 Pseudotsuga menziesii Douglas firPinaceae N 5 Shrubs/Subshrubs Acer glabrum Rocky Mountain mapleSapindaceae N 7 Alnus incana subsp. tenuifolia Thinleaf alderBetulaceae N 6 Amelanchier alnifolia ServiceberryRosaceae N 6 Artemisia tridentata var. vaseyana Mountain big sagebrushAsteraceae N 5 Ceanothus velutinus Sticky laurelRhamnaceae N 7 Chrysothamnus viscidiflorus Sticky rabbitbrushAsteraceae N 5 Cornus sericea subsp. sericea Redosier dogwoodCornaceae N 7 Juniperus communis subsp. alpina Common juniperCupressaceae N 6 Mahonia repens Oregon grapeBerberidaceae N 5 Paxistima myrsinites Mountain loverCelastraceae N 7 Potentilla fruticosa ( Shrubby cinquefoilRosaceae N 4 =Pentaphylloides floribunda) Prunus virginiana var. melanocarpa ChokecherryRosaceae N 4 Quercus gambelii Gambel oakFagaceae N 5 Ribes inerme Whitestem gooseberryGrossulariaceae N 5 Ribes wolfii Wolf's currantGrossulariaceae N 7 Rosa woodsii Woods' roseRosaceae N 5 Rubus idaeus var. strigosus Red raspberryRosaceae N 5 Salix bebbiana Bebb willowSalicaceae N 6 Salix drummondiana Drummond's willowSalicaceae N 6 Salix eriocephala var. ligulifolia Strapleaf willowSalicaceae N 7 Salix geyeriana Geyer willowSalicaceae N 6 Salix lasiandra var. caudata Whiplash willowSalicaceae N 7

Friday, June 7, 2019 Page 1 of 8 Scientific Name Common Name Family Origin C‐ Voucher Value Photo

Salix monticola Mountain willowSalicaceae N 6 Sambucus microbotrys Red elderberryAdoxaceae N 6 Shepherdia canadensis BuffaloberryElaeagnaceae N 7 Symphoricarpos rotundifolius (=S. Roundleaf snowberryCaprifoliaceae N 5 oreophilus) Vaccinium myrtillus WhortleberryEricaceae N 6 Perennial Graminoids Achnatherum lettermanii Letterman's needlegrassPoaceae N 6 Agropyron cristatum (=A. Crested wheatgrassPoaceae I 0 desertorum) Agrostis gigantea RedtopPoaceae I 0 Alopecurus pratensis Meadow foxtailPoaceae I 0 Bromelica spectabilis Purple oniongrassPoaceae N 8 Bromus carinatus (=Ceratochloa) bromePoaceae N 5 Bromus ciliatus (=Bromopsis Fringed bromePoaceae N 5 canadensis) Bromus inermis Smooth bromePoaceae I 0 Carex aquatilis Water sedgeCyperaceae N 6 Carex bebbii Bebb's sedgeCyperaceae N 7 Carex disperma Softleaf sedgeCyperaceae N 9 Carex geyeri Elk sedgeCyperaceae N 6 Carex microptera Smallwing sedgeCyperaceae N 4 Carex praegracilis Clustered field sedgeCyperaceae N 5 Carex praticola meadow sedgeCyperaceae N 6 Carex utriculata Beaked sedgeCyperaceae N 5 Dactylis glomerata OrchardgrassPoaceae I 0 Danthonia intermedia Timber oatgrassPoaceae N 8 Eleocharis palustris Creeping spikerushCyperaceae N 3 Elymus elymoides SquirreltailPoaceae N 4 Elymus glaucus Blue wildryePoaceae N 7 Elymus lanceolatus Thickspike wheatgrassPoaceae N 4 Elymus trachycaulus Slender wheatgrassPoaceae N 4 Elytrigia repens QuackgrassPoaceae I 0

Friday, June 7, 2019 Page 2 of 8 Scientific Name Common Name Family Origin C‐ Voucher Value Photo

Festuca idahoensis Idaho fescuePoaceae N 7 Festuca rubra Red fescuePoaceae N 5 Festuca saximontana Rocky Mountain fescuePoaceae N 7 Glyceria striata Fowl mannagrassPoaceae N 6 Hesperostipa comata Needle and thread grassPoaceae N 6 Hordeum jubatum Foxtail barleyPoaceae N 2 Juncus arcticus var. balticus (=J. Baltic rushJuncaceae N 4 balticus) Juncus drummondii Drummond's rushJuncaceae N 6 Juncus ensifolius (=J. saximontanus) Swordleaf rushJuncaceae N 6 Koeleria macrantha Prairie JunegrassPoaceae N 6 Nassella viridula (=Stipa) Green needlegrassPoaceae N 4 Pascopyrum smithii Western wheatgrassPoaceae N 5 Phalaris arundinacea Reed canarygrassPoaceae I 0 Phleum pratense TimothyPoaceae I 0 Poa compressa Canada bluegrassPoaceae I 0 Poa palustris Fowl bluegrassPoaceae N 6 Poa pratensis Kentucky bluegrassPoaceae I 0 Schedonorus arundinacea (=Festuca) Tall fescuePoaceae I 0 Schedonorus pratensis (=Festuca) Meadow fescuePoaceae I 0 Schoenoplectus tabernaemontani Softstem bulrushCyperaceae N 3 Scirpus microcarpus Panicled bulrushCyperaceae N 5 Perennial Forbs Achillea lanulosa YarrowAsteraceae N 4 Aconitum columbianum MonkshoodRanunculaceae N 8 Agastache urticifolia Nettleleaf giant hyssopLamiaceae N 5 Anaphalis margaritacea Pearly everlastingAsteraceae N 4 Androsace septentrionalis Pygmyflower Primulaceae N6 rockjasmine Angelica ampla Giant angelicaApiaceae N 4 Antennaria parvifolia Small‐leaf pussytoesAsteraceae N 5 Arenaria lanuginosa subsp. saxosa Spreading sandwortCaryophyllaceae N 5 (=Spergulastrum)

Friday, June 7, 2019 Page 3 of 8 Scientific Name Common Name Family Origin C‐ Voucher Value Photo

Artemisia dracunculus (=Oligosporus) Wild tarragonAsteraceae N 3 Artemisia ludoviciana White sageAsteraceae N 4 Boechera lignifera Desert rockcressBrassicaceae N 8 Boechera stricta (=B. drummondii) Drummond's rockcressBrassicaceae N 5 Campanula parryi Parry's bellflowerCampanulaceae N 7 Campanula rotundifolia HarebellCampanulaceae N 5 Castilleja linariifolia Narrowleaf Indian Orobanchaceae N6 paintbrush Castilleja miniata Giant red Indian Orobanchaceae N7 paintbrush Castilleja sulphurea Sulphur Indian Orobanchaceae N7 paintbrush Cirsium arvense (=Breea) Canada thistleAsteraceae I B 0 Cirsium eatonii Eaton's thistleAsteraceae N 6 Cymopterus lemmonii Moutain spring parsleyApiaceae N 6 (Pseudocymopterus montanus) Delphinium ramosum Mountain larkspurRanunculaceae N 5 arguta Tall cinquefoilRosaceae N 7 Epilobium ciliatum American willowherbOnagraceae N 4 Epilobium halleanum Glandular willowherbOnagraceae N 8 Eremogone congesta Ballhead sandwortCaryophyllaceae N 8 Erigeron eximius Splendid fleabaneAsteraceae N 7 Erigeron flagellaris Trailing fleabaneAsteraceae N 3 Erigeron speciosus Aspen fleabaneAsteraceae N 5 Eriogonum umbellatum Sulphur‐flower Polygonaceae N6 buckwheat Eucephalus engelmannii Engelmann's asterAsteraceae N 7 Fragaria virginiana Mountain strawberryRosaceae N 5 Frasera speciosa Monument plant, Gentianaceae N6 Elkweed Galium boreale (=G. septentrionale) Northern bedstrawRubiaceae N 6 Gentiana parryi (=Pneumonanthe) Parry's gentianGentianaceae N 9 Geranium richardsonii Richardson's geraniumGeraniaceae N 6

Friday, June 7, 2019 Page 4 of 8 Scientific Name Common Name Family Origin C‐ Voucher Value Photo

Geranium viscosissimum subsp. Sticky purple geraniumGeraniaceae N 5 nervosum Geum macrophyllum var. perincisum Largeleaf avensRosaceae N 6 Geum rivale Purple avensRosaceae N 5 Goodyera oblongifolia Rattlesnake plantain Orchidaceae N9 orchid Helianthella quinquenervis Fivenerve little N7 sunflower Heracleum maximum (=H. Cow parsnipApiaceae N 6 sphondylium subsp. montanum) Heterotheca villosa Hairy false goldenasterAsteraceae N 3 Ipomopsis aggregata Scarlet giliaPolemoniaceae N 5 Iris missouriensis Rocky Mountain irisIridaceae N 4 Lathyrus lanszwerti var. leucanthus Whiteflower peaFabaceae N 6 (=L. leucanthus) Leucanthemum vulgare Oxeye daisyAsteraceae I B 0 Ligularia bigelovii var. hallii Hall's ragwortAsteraceae N 7 Ligusticum porteri Osha, lovageApiaceae N 7 Linaria vulgaris Butter and eggs, toadflaxPlantaginaceae I B 0 Linum lewisii (=Adenolinum) Wild blue flaxLinaceae N 4 Lupinus argenteus Silvery lupineFabaceae N 5 Maianthemum stellatum Starry false Solomon's Ruscaceae N7 seal Malva neglecta Common mallowMalvaceae I 0 Melandrium dioicum Red catchflyCaryophyllaceae I 0 Mertensia ciliata Chiming bellsBoraginaceae N 7 Nepeta cataria CatnipLamiaceae I 0 Osmorhiza depauperata Bluntseed sweet cicelyApiaceae N 7 Osmorhiza occidentalis Western sweet cicelyApiaceae N 7 multilobata Lobeleaf groundselAsteraceae N 5 Packera pseudaurea Falsegold groundselAsteraceae N 7 Pedicularis procera Giant lousewortOrobanchaceae N 8 Penstemon strictus Rocky Mountain Plantaginaceae N5 penstemon

Friday, June 7, 2019 Page 5 of 8 Scientific Name Common Name Family Origin C‐ Voucher Value Photo

Persicaria amphibia Water smartweedPolygonaceae N 4 Piperia unalascensis Slender‐spire orchidOrchidaceae N 10 Plantago lanceolata Narrowleaf plantainPlantaginaceae I 0 Platanthera aquilonis Northern green orchidOrchidaceae N 7 Woolly cinquefoilRosaceae N 5 Potentilla pulcherrima Beautiful cinquefoilRosaceae N 5 Potentilla recta Sulphur cinquefoilRosaceae I B 0 Prunella vulgaris Common selfhealLamiaceae N 4 chlorantha Greenflowered N8 wintergreen Pyrola rotundifolia subsp. asarifolia Roundleaf wintergreenEricaceae N 8 Ranunculus macounii Macoun's buttercupRanunculaceae N 7 Rorippa palustris Bog yellowcressBrassicaceae N 4 Rumex acetosella (=Acetosella Sheep sorrelPolygonaceae I 0 vulgaris) Sedum lanceolatum StonecropCrassulaceae N 5 Senecio eremophilus var. kingii King's ragwort; Cutleaf Asteraceae N4 groundsel Senecio integerrimus Lambstongue groundselAsteraceae N 5 Senecio serra var. admirabilis Tall ragwortAsteraceae N 7 Sidalcea candida White checkermallowMalvaceae N 5 Stellaria longipes Longstalk starwortCaryophyllaceae N 8 Symphyotrichum ascendens Western asterAsteraceae N 2 (=Virgulaster) Symphyotrichum foliaceum (=Aster) Leafy bracted asterAsteraceae N 5 Symphyotrichum laeve var. geyeri Smooth blue asterAsteraceae N 6 (=Aster) Symphyotrichum lanceolatum subsp. White panicle asterAsteraceae N 5 hesperium (=Aster) Taraxacum officinale DandelionAsteraceae I 0 Thalictrum fendleri Fendler's meadow‐rueRanunculaceae N 6 Trifolium pratense Red cloverFabaceae I 0 Trifolium repens White cloverFabaceae I 0 Typha latifolia Broadleaf cattailTyphaceae N 2

Friday, June 7, 2019 Page 6 of 8 Scientific Name Common Name Family Origin C‐ Voucher Value Photo

Urtica dioica Stinging nettleUrticaceae N 3 Valeriana edulis Tobacco root; Edible Valerianaceae N7 valerian Veratrum tenuipetalum (=V. False helleboreMelanthiaceae N 4 californicum) Vicia americana American vetchFabaceae N 5 Viola scopulorum Canadian white violetViolaceae N 7 Ferns and Fern Allies Equisetum hyemale subsp. affine Scouringrush horsetailEquisetaceae N 4 (=Hippochaete) Annual/Biennial Forbs Berteroa incana Hoary alyssumBrassicaceae I W 0 Camelina microcarpa False flaxBrassicaceae I 0 Capsella bursa‐pastoris Shepherd's purseBrassicaceae I 0 Carduus acanthoides Plumeless thistleAsteraceae I B 0 Chenopodium atrovirens Pinyon goosefootChenopodiaceae N 5 Collomia linearis Narrowleaf mountain Polemoniaceae N4 trumpet Cynoglossum officinale HoundstongueBoraginaceae I B 0 Descurainia incana Mountain tansymustardBrassicaceae N 2 Galeopsis bifida Splitlip hempnettleLamiaceae I 0 Gayophytum diffusum subsp. Diffuse groundsmokeOnagraceae N 4 parviflorum Hackelia floribunda Manyflower stickseedBoraginaceae N 3 Lepidium densiflorum Common pepperweedBrassicaceae I 0 Melilotus officinale Yellow sweetcloverFabaceae I 0 Polygonum douglasii Douglas' knotweedPolygonaceae N 3 Tragopogon dubius subsp. major Western salsifyAsteraceae I 0 Tragopogon pratensis Meadow salsifyAsteraceae I 0 Tripleurospermum perforatum Scentless chamomileAsteraceae I B 0 Verbascum thapsus MulleinScrophulariaceae I C 0 Annual Graminoids

Friday, June 7, 2019 Page 7 of 8 Scientific Name Common Name Family Origin C‐ Voucher Value Photo

Beckmannia syzigachne subsp. American sloughgrassPoaceae N 4 baicalensis

Notes: Nomenclature generally follows Flora of Colorado (Ackerfield 2015) with Weber and Wittmann (2012) synonyms in parantheses. Origin: N=Native; I=Introduced, I+A,B,C,W = Colorado Listed Noxious Weed and Rank. C‐Value from Rocchio (2007), where 0 (non‐ native species); 1‐3 (commonly found in non‐natural areas), 4‐6 (equally found n natural and non‐natural areas); 7‐9 (obligate to natural areas but can sustain some habitat degredation); 10 (obligate to high quality natural areas (relatively unaltered from pre‐ European settlement). Voucher / Photo: checkmark indicates whether a voucher and/or photograph were taken, respectively. List Prepared by Rea Orthner of Peak Ecological Services LLC. of Nederland, CO.

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