The Uncompahgre River Basin A Natural Heritage Assessment Volume I Prepared for Valley Land Conservancy Montrose, Colorado March, 1999 By Peggy Lyon, Tom Stephens, Jeremy Siemers, Denise Culver, Phyllis Pineda, and Jennifer Zoerner Colorado Natural Heritage Program 254 General Services Building, CSU Ft. Collins, CO 80523 User’s Guide The Uncompahgre Basin Biological Assessment conducted by the Colorado Natural Heritage Program consists of two essentially distinct projects that are highly integrated with respect to methodology and fieldwork. This report reflects the separate nature of the projects by being organized in a two-volume set. Volume I presents all potential conservation sites that have been identified in the Uncompahgre Basin that support rare and imperiled plants, animals, and significant plant communities, including wetland and riparian areas. Volume II focuses exclusively on wetland and riparian areas. Volume II also presents “locally significant areas.” These are sites that are among the most important wetlands in the Uncompahgre Basin, but they are not unique from a national or statewide perspective, and therefore these sites did not receive a Biodiversity Rank. Additionally, Volume II presents an assessment of the wetland functions performed by each site that was surveyed. These functional assessments are intended to provide the user with a more complete picture of the value wetlands and riparian areas provide to Uncompahgre Basin residents. Both projects utilized the same Natural Heritage Methodology that is used throughout North America, and both searched for and assessed the plants, animals, and plant communities on the Colorado Natural Heritage Program’s List of rare and imperiled elements of biodiversity. Each volume prioritizes potential conservation sites based on the relative significance of the biodiversity they support and the urgency for protection of the site. All information explaining Natural Heritage Methodology and ranks is repeated in each volume, so that each volume can stand alone and be used independently of the other. ACKNOWLEDGEMENTS This project would not have been possible without the help of numerous dedicated individuals. We appreciate the support of the Montrose and Ouray County Commissioners and the assistance that both County Assessors’ Offices gave us in determining land ownership. We received much help from the Bureau of Land Management, especially Jim Ferguson and Amanda Clements; Colorado Division of Wildlife, especially Ken Miller, Rick Sherman, and Jim Garner; the U. S. Forest Service, especially Craig Grother; and the National Park Service, especially Nancy Zaenger and Myron Chase. We are grateful to the U.S. Environmental Protection Agency, Region VIII and the Colorado Department of Natural Resources for providing continual funding and support of wetland inventories and assessment in Colorado Members of the Colorado Native Plant Society, as well as other individuals, volunteered to help in the field. We thank Joan Schmidt; Peggy Howe, Cindy Carlson, Virginia Taylor, Reda Vilner, Sandy Beranich, and Paula Tyler for accompanying us on sometimes challenging trips. Most of all, we thank Shu Fujisawa, who dedicated his entire summer vacation from CSU to work on the project. He added many insights and asked thoughtful questions. We appreciate the many landowners that gave us permission to survey their property. In many cases, they imparted to us knowledge that they had gained from many years’ experience in caring for the land. Our staff in Fort Collins, including Mary Klein, Jill Handwerk, Susan Spackman, Kim Fayette, Renee Rondeau, Barry Baker, Amy Lavender, and Mike Wunder all worked with us patiently. Finally, we thank Valley Land Conservancy and its director, Tony Hoag, for sponsoring the project, and Great Outdoors Colorado for providing the funding. Executive Summary The Uncompahgre Basin is experiencing a period of rapid growth. Citizens of Montrose and Ouray counties have expressed concerns over the loss of open space, wildlife habitat, and their unique natural surroundings. They have recognized the need to plan for the conservation of plants and animals that are native to the Uncompahgre Basin, especially those that depend on this area for their survival. In 1997, The Valley Land Conservancy (VLC), The Nature Conservancy, and the Colorado Natural Heritage Program (CNHP) proposed to the Montrose and Ouray County Board of County Commissioners that a biological assessment be conducted for the eastern part of Montrose County and all of Ouray County. The goal of the project would be to systematically identify the localities of rare, threatened, or endangered species and the locations of significant natural plant communities. In addition, CNHP and VLC offered to conduct workshops with the county commissioners, county planning departments and interested local groups to present the results of the study and assist in protection efforts. Funding for the biological assessment was obtained from a Great Outdoors Colorado planning grant to the Valley Land Conservancy, who contracted with Colorado Natural Heritage Program to perform the survey. At the same time, the U. S. Environmental Protection Agency, through the Colorado Department of Natural Resources, provided CNHP with support to conduct a wetland and riparian survey of the private lands of the Uncompahgre Basin. These two projects were closely coordinated and the results are presented in the two volumes of this report. Volume I represents the Biological Assessment, while Volume II presents the wetland and riparian study. Colorado Natural Heritage Program began its research by updating its Biological and Conservation Data System with existing information. This was drawn from previous studies by various individuals and organizations, including the Colorado Division of Wildlife (CDOW) database, regional and local herbaria, local experts, federal agencies, and others. Based on these data, we identified over 200 targeted inventory areas (TIAs) for field research (Appendix I). More areas of interest were added to this list during the field season. Field surveys began in April 1998 and continued through November 1998. Results of the survey confirm that the Uncompahgre Basin contains a number of plant species endemic to western Colorado, which depend on this area for their existence. Due to unusual geological and soil substrates, the world’s population of several species is restricted to a relatively small geographic area, comprising only small parts of two or three counties. We found that riparian zones and salt desert shrublands are the most locally threatened plant communities. Several plants and animals were found to be more common than had been thought, and will no longer be tracked by CNHP. Forty-four species and communities were documented for the first time in the CNHP database for Montrose and Ouray counties. We have identified sixty-five Proposed Conservation Areas (PCAs), containing 254 occurrences of rare or imperiled plants, animals, and natural communities. Each is ranked according to its relative biodiversity significance. Results of the survey are presented here, with descriptions and recommendations for each Proposed Conservation Area. The results will also be provided to the counties and VLC in GIS format, and will be available to the public on the CNHP website (http:\\www.colostate.edu/orgs/CNHP). The delineation of Proposed Conservation Area boundaries in this report does not confer any regulatory protection on recommended areas. They are intended to be used to support wise planning and decision making for the conservation of these significant areas. Additional information may be requested from Colorado Natural Heritage Program, 254 General Services Building, Colorado State University, Fort Collins, CO 80523. TABLE OF CONTENTS Page Preface - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 1 Methods- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 3 Results- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 4 Recommendations- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 5 The Natural Heritage of the Uncompahgre Basin Physical Characteristics- - - - - - - - - - - - - - - - - - - - - - - - - - - -8 Vegetation- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 15 Weeds- - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 31 Rare and imperiled plants- - - - - - - - - - - - - - - - - - - - - - - - - - - 34 Rare and imperiled animals- - - - - - - - - - - - - - - - - - - - - - - - - - 48 Proposed Conservation Areas - - - - - - - - - - - - - - - - - - - - - - - 54 (PCAs followed by * are also discussed in Volume II.) MACROSITES - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 60 Uncompahgre River* B3 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 60 Uncompahgre Badlands B2 - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 67 B2 PROPOSED CONSERVATION AREAS - - - - - - - - - - - - - - - - - - - - - 73 Billy Creek - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 73 Cedar Creek - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 76 Cerro Summit - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 79 Cimarron - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 81 Cimarron SWA* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - 83 Colona