Plant Communities of Capitol Reef National Park, Utah William H. Romme, Kenneth D. Heil, J. Mark Porter, and Rich Fleming Technical Report NPS/NAUCARE/NRTR-93/02 National Park Service Cooperative Park Studies Unit U.S. Department of the Interior at Northern Arizona University National Park Service Cooperative Park Studies Unit Northern Arizona University The National Park Service (NPS) Cooperative Park Studies Unit (CPSU) at Northern Arizona University (NAU) is unique in that it was conceptualized for operation on an ecosystem basis, rather than being restrained by state or NPS boundaries. The CPSU was established to provide research for the 33 NPS units located within the Colorado Plateau, an ecosystem that shares similar resources and their associated management problems. Utilizing the university's physical resources and faculty expertise, the CPSU facilitates multidisciplinary research in NPS units on the Colorado Plateau, which encompasses four states and three NPS regions—Rocky Mountain, Southwest, and Western. The CPSU provides scientific and technical guidance for effective management of natural and cultural resources within those NPS units. The National Park Service disseminates the results of biological, physical, and social science research through the Colorado Plateau Technical Report Series. Natural resources inventories and monitoring activities, scientific literature reviews, bibliographies, and proceedings of techni­ cal workshops and conferences are also disseminated through this series. Unit Staff Charles van Riper, III, Unit Leader Peter G. Rowlands, Research Scientist Henry E. McCutchen, Research Scientist Mark K. Sogge, Ecologist Charles Drost, Zoologist Elena T. Deshler, Biological Technician Paul R. Deshler, Technical Information Specialist Connie C. Cole, Editor Margaret Rasmussen, Administrative Clerk Jennifer Henderson, Secretary National Park Service Review Documents in this series contain information of a preliminary nature and are prepared primarily for internal use within the National Park Service. This information is not intended for use in open literature. This report has been reviewed and approved for dissemination by the National Park Service. Approval does not signify that the contents necessarily reflect the views and policies of the National Park Service nor does mention of trade names or commercial products constitute endorsement or recommendation for use. Copies of this report are available from the following. To order from the National Park Service, Technical Information Center, use the reference number on the bottom of the report's inside back cover. National Park Service National Park Service Cooperative Park Studies Unit Technical Information Center Northern Arizona University Denver Service Center P. O. Box 5614 P. O. Box 25287 Flagstaff, AZ 86011-5614 Denver, CO 80225-0287 (602) 556-7466 (303) 969-2130 Plant Communities of Capitol Reef National Park, Utah William H. Romme1 Kenneth D. Heil2, J. Mark Porter3, and Rich Fleming2 'Fort Lewis College, Durango, Colorado 2San Juan College, Farmington, New Mexico 3Rancho Santa Ana Botanic Garden, Claremont, California Technical Report NPS/NAUCARE/NRTR-93/02 September 1993 National Park Service Cooperative Park Studies Unit U.S. Department of the Interior at Northern Arizona University Capitol Reef National Park was established in 1971 as a 241,000 acre park in the heart of the Colorado Plateau. The law creating the park called for the immediate phase-out of livestock grazing. In 1982, controversy surrounding the required phase-out precipitated the passage of a second law which called for an extension of grazing activities. This law also called for the establishment of a comprehensive grazing research program, initially overseen by the National Academy of Sciences, to determine the effects of the activity on the park's natural and cultural resources. By 1991, with NPS funding, the Division of Resource Management and Science at Capitol Reef National Park eventually shepherded to completion 11 separate studies as part of this effort. This document is the second report to be published as part of this grazing research series. Norman R. Henderson Chief, Resource Management and Science Capitol Reef National Park Table of Contents List of Tables iv Abstract 1 Introduction 1 Part I: Description of the Plant Communities and Phases 3 Part II: Fitting CARE's Plant Communities into the Brown-Lowe-Pase System 21 Part III: Producing a Vegetation Map for CARE Using GIS 27 Acknowledgements 29 Literature Cited 31 Appendix 1: Key to Plant Communities in Capitol Reef National Park 35 iii List of Tables Table 1. Summary of community types and phases in Capitol Reef National Park 2 Table 2. Summary of plant community types and phases in Capitol Reef National Park (CARE) and comparable vegetation units that have been described in systematic classifications elsewhere on the Colorado Plateau 21 Table 3. Preliminary classification of plant communities and phases in CARE according to the Brown, Lowe, and Pase (1979) system 24 Table 4. Boolean combinations of existing data layers in the GIS to produce the vegetation map as a new map layer 27 Table 5. Definitions of complexes on the vegetation map 29 IV Plant Communities of Capitol Reef National Park, Utah Abstract Thirty-four community types and thirteen region. Of the 34 community types in CARE, phases were identified and described in 23 comparable types have been described in Capitol Reef National Park (CARE). A com­ surrounding areas, and the remaining 11 munity was defined as a more or less unique either are unique to CARE or simply have not and repeated assemblage of plant species been described elsewhere. Those communities occupying sites characterized by a more or that to date have been described only from less unique combination of elevation and soil CARE include the hopsage badlands, sage- texture conditions. A phase is a recognizable brush-bitterbrush, bristlecone pine-cushion subunit of a community type, characterized by plant, mesic montane woodland, cottonwood- a somewhat unusual assemblage of species rabbifbrush woodland, waterpocket, alder- and occupying a portion of the usual habitat birch, dogwood-spruce, hornbeam-boxelder- for that community type with no recognizably oak woodland, cultivated orchards and settle­ unique environmental conditions. Phases may ments, and perennial wetland communities. reflect subtle, unrecognized patterns in under­ Several of the community types in CARE do lying environmental gradients; or unique not readily fit any of the units in the original historical events of dispersal, establishment, BLP system, suggesting that some new or disturbance; or both. They cannot be subassociations, associations, series, and mapped reliably, but they contribute to the formations may be needed to accommodate park's biological diversity. A dichotomous key the distinctive plant communities of the is provided for field identification of commu­ Colorado Plateau. nities and phases in CARE. A map of CARE vegetation can be pro­ The system of communities and phases duced by overlaying existing data layers using developed for CARE was compared with a geographic information system (GIS). Detailed other classification systems developed else­ instructions are provided for making a map where on the Colorado Plateau, and with based on the combinations of elevation, sub­ the Brown-Lowe-Pase (BLP) system being strate, slope aspect, and physiognomic vegeta­ adopted in all National Park units in the tion class associated with each community type. Introduction The vegetation of Capitol Reef National vegetation types that already exists in the Park (CARE) is complex and diverse. Heil et park's geographic information system (GIS). al. (1993) provide an overview of the plant Plant species distribution in CARE is communities and vegetation patterns in controlled primarily by gradients in elevation CARE, as well as the vascular flora and and soil texture, the latter being determined general environmental conditions in the park. mainly by geologic substrate. In many areas, The objectives of this companion paper are to: plant species abundance has been altered (1) describe each plant community in greater greatly by heavy livestock grazing. Topo­ detail; (2) compare the plant communities and graphic position and aspect influence species classification system developed in CARE with distribution and abundance in a few places, communities and classifications elsewhere on but are not major controlling factors in plant the Colorado Plateau—in particular, with the distribution (unlike many other regions). See Brown-Lowe-Pase system being adopted Heil et al. (1993) for gradient analyses of throughout the region; and (3) present the CARE vegetation and an analysis of grazing rationale and methodolgy for producing a effects. vegetation map of CARE by use of informa­ The vegetation in Capitol Reef National tion on geology, elevation, and physiognomic Park appears to be a continuum rather than a 1 Technical Report NPS/NAUCARE/NRTR-93/02 series of discrete units, except where under­ species and occupying a portion of the usual lying physical factors, such as soil texture or habitat for that community type with no moisture, change abruptly. The communities recognizably unique environmental condi­ that we describe below are not the communities tions. Phases may reflect subtle, unrecog­ of Clements and Daubenmire; rather they are nized patterns in underlying environmental recognizable assemblages of plant species that gradients;