Rare Plant Survey of the Canon City Hogback Prepared by Susan Spackman Panjabi, Botanist Jill Handwerk, Botanist Stephanie L. Neid, Ecologist Colorado Natural Heritage Program Colorado State University Prepared for John Nichols, Director of Parks City of Canon City December 31, 2009 Table of Contents Introduction 3 Methods 4 Results 4 Canon City Hogback Potential Conservation Area 5 Discussion 8 Recommendations 8 Acknowledgements 8 References 9 Appendix I Species Profiles 10 Appendix II Natural Heritage Network Ranking System 19 2 Introduction To facilitate the completion of a management plan for the Hogback west of Canon City, the Colorado Natural Heritage Program (CNHP) at Colorado State University (CSU) was contracted by Canon City to survey approximately 300 acres of City property for rare plant species listed by the Natural Heritage Network (NatureServe 2009, CNHP 2009). An additional 200 acres of private land adjacent to the City property was also surveyed. Rare plant species known from or potentially found on the Hogback are listed in Table 1. This survey collected and updated botanical information at this location for use in a management plan for the area. For additional background information about CNHP and the Natural Heritage Network, please see Appendix II. Table 1: Target species for surveys at study site. Nomenclature follows PLANTS Database (USDA 2007) for global scientific name and common name and Weber and Wittmann (2001) for state scientific name. See also http://www.cnhp.colostate.edu/ tracking/ vascular.html. Global Scientific State Scientific Global State Flowering Common Name Name Name Rank1 Rank1 Period Argyrochosma Argyrochosma Fendler cloak G3 S3 n/a fendleri fendleri Eriogonum Eriogonum Brandegee wild G1G2 S1S2 July-August brandegeei brandegeei buckwheat Lesquerella Lesquerella Rocky Mountain G2 S2 late May- calcicola calcicola bladderpod early June Mentzelia Nuttallia chrysantha golden blazing G2 S2 July-early chrysantha2 star September Mentzelia densa Nuttallia densa Arkansas Canyon G2 S2 July stickleaf Mirabilis Oxybaphus round-leaf four- G2 S2 June rotundifolia rotundifolius o'clock Oenothera Oenothera Arkansas Valley G2G3 S2S3 mid May- harringtonii harringtonii evening primrose June Oonopsis sp 1 Oonopsis Pueblo golden G2 S2 July puebloensis weed Parthenium Bolophyta Arkansas River G3 S3 April-May tetraneuris tetraneuris fever-few Pellaea wrightiana Pellaea wrightiana Wright’s G5 S2 n/a cliffbrake Townsendia fendleri Townsendia Fendler’s G2 S2 August- fendleri Townsend daisy September 1Information on ranking system found in Appendix One and at http://www.cnhp.colostate.edu/heritage.html 2This species was known to occur on the Hogback prior to the study. 3 Methods In an effort to optimize the detection of the target species, field surveys were conducted on June 3, 2009 and August 13, 2009, when these species are usually in flower. We covered as much area as possible, directing search efforts primarily to shale substrates that are known to support rare plants. Surveys were conducted by hiking through inventory areas, inspecting typical habitat as well as unusual edaphic or topographic features (e.g., rock outcrops, moist depressions, etc.). During the field surveys, as new locations for any of the plant species of concern were found (Table 1), we recorded habitat information including precise location, size of area, associated species, substrate, slope, aspect, percent vegetation cover, and levels of natural and human disturbance. We recorded population information including approximate number of individuals, approximate density of individuals, evidence of reproductive success, and evidence of natural or human induced threats. Data for rare species found were entered into the CNHP Biotics Database. Results Three new occurrences of three globally imperiled plants were found on Canon City property at the Canon City Hogback site. This new information was combined with existing data for the area to expand and develop the Canon City Hogback Potential Conservation Area, detailed below. Element occurrence records for the species found on the Canon City Hogback, and the site record for the Potential Conservation Area are being provided to the City in electronic and GIS format. 4 Canon City Hogback Biodiversity Rank - B2: Very High Biodiversity Significance Protection Urgency Rank - P3: Definable Threat/Opportunity but not within 5 Years Management Urgency Rank - M3: Needed within 5 Years to Maintain Quality U.S.G.S. 7.5-minute quadrangles: Royal Gorge, Canon City, Rice Mountain, Cooper Mountain Size: 1,622 acres (657 ha) Elevation: 5,377 - 6,217 ft. (1,639 - 1,895 m) General Description: The site is characterized by a north-south running hogback and adjacent foothills habitat. The hogback is on the edge of the Canon City Embayment, a geological feature derived during the inland seas of the Cretaceous; it curves around the base of the foothills just west of Canon City. The hogbacks are blanketed by pinon - juniper woodlands with both grassland and barrens openings. The intervening valleys are grasslands. The dominant plant community adjacent to the relatively barren shale outcrops is pinon pine (Pinus edulis) - juniper (Juniperus spp.) / mountain mahogany (Cercocarpus montanus) woodlands. Additional associated plant species include branched noseburn (Tragia ramosa), desert pricklypear (Opuntia phaeacantha), James' buckwheat (Eriogonum jamesii), purple threeawn (Aristida purpurea), Colorado four o'clock (Mirabilis multiflora), blackfoot daisy (Melampodium leucanthum), James' galleta (Hilaria jamesii), and spider milkweed (Asclepias asperula). Biodiversity Significance Rank Comments (B2): The site supports a good (B-ranked) and a fair to poor (CD-ranked) occurrence of the globally imperiled (G2/S2) round-leaf four-o'clock (Oxybaphus rotundifolius), a good (B-ranked) occurrence of the globally imperiled (G2/S2) Rocky Mountain bladderpod (Lesquerella calcicola), a good to fair (BC-ranked) occurrence of the globally imperiled (G2/S2) Fendler's townsend-daisy (Townsendia fendleri), and a good (B-ranked) occurrence of the globally imperiled (G2/S2) golden blazing star (Nuttallia chrysantha). 1 Natural Heritage element occurrences at the Canon City Hogback PCA. Last State Scientific State Common Global State Federal State Fed EO Obs Major Group Name Name Rank Rank Status Status Sens Rank Date Vascular Lesquerella Rocky Mountain G2 S2 B 2006- Plants calcicola bladderpod 08-10 Vascular Nuttallia golden blazing G2 S2 BLM B 2009- Plants chrysantha star 08-13 Vascular Oxybaphus round - leaf four G2 S2 CD 2009- Plants rotundifolius - o'clock 06-03 Vascular Oxybaphus round - leaf four G2 S2 B 2006- Plants rotundifolius - o'clock 08-10 Vascular Townsendia Fendler's G2 S2 BC 2009- Plants fendleri townsend - daisy 08-13 ** The records above are sorted in the following order 1) Major Group 2) Global Rank and 3) Scientific name. Boundary Justification: The boundary is drawn to include the known occurrences, additional potential habitat, and the local mosaic of plant communities. The boundary was digitized while referencing a one meter digital color orthophoto quad and a 1:100,000 digital quad. Protection Urgency Rank Comments (P3): Canon City owns the southern portion of the site and manages it for recreational use. Specific land ownership patterns for the full site are not known (land status maps indicate that the entire site is privately owned). Some state-recognized lands are located in the northern portion of the site. Management Urgency Rank Comments (M3): The site would benefit from periodic monitoring to assure continued or improved quality and condition of the rare plant occurrences. References - Version Author: Panjabi, S.S. Version Date: 09/24/2009 2 Miles 0 1 2 ± Colorado Natural Heritage Program Legend Colorado State University Location in the Fremont County 254 General Services Building PCA Boundary 1474 Campus Delivery Royal Gorge, 38105-D2 Fort Collins, CO 80523-1474 Cooper Mountain, 38105-E2 Canon City, 38105-D2 Ph (970) 491-1309 Rice Mountain, 38105-E3 Fax (970) 491-3349 www.cnhp.colostate.edu 7.5 Minute Digital Raster Graphic Produced by the U.S. Geological Survey Map Date: 12/03/2009 Canon City Hogback Potential Conservation Area, B2: Very High Biodiversity Significance Discussion Despite its small size the Canon City Hogback property is significant because it supports several high quality and viable occurrences of globally imperiled plant species. More detailed information about each of the globally imperiled plants is provided in Appendix I.. Additional survey work at the Canon City Hogback may identify additional locations for these species. Recommendations A full inventory, conducted over a period from early spring through late fall could identify additional species, quite possibly including other imperiled species such as Oenothera harringtonii (Arkansas Valley evening primrose) or Oonopsis puebloensis (Pueblo goldenweed). These species are also known only from the Arkansas River Valley and are known from similar habitats as the shale barrens found on the Canon City Hogback. Future research could aim to make collections of all of the plant species on the Canon City Hogback site, so that the floristic diversity is better documented. The low areas between the hogbacks at the site would be suitable for revegetation and restoration work. Local weed management organizations could be consulted to assist the City with the eradication and/or control/containment of non-native plants. Trails could be consolidated