USDA United States Department of Representativeness Assessment of Agriculture Forest Service Research Natural Areas on Rocky Mountain Research Station National Forest System Lands General Technical Report RMRS-GTR-45 in Idaho March 2000 Steven K. Rust Abstract Rust, Steven K. 2000. Representativeness assessment of research natural areas on National Forest System lands in Idaho. Gen. Tech. Rep. RMRS-GTR-45. Fort Collins, CO: U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station. 129 p. A representativeness assessment of National Forest System (N FS) Research Natural Areas in ldaho summarizes information on the status of the natural area network and priorities for identification of new Research Natural Areas. Natural distribution and abundance of plant associations is compared to the representation of plant associations within natural areas. Natural distribution and abundance is estimated using modeled potential natural vegetation, published classification and inventory data, and Heritage plant community element occur- rence data. Minimum criteria are applied to select only viable, high quality plant association occurrences. In assigning natural area selection priorities, decision rules are applied to encompass consideration of the adequacy and viability of representation. Selected for analysis were 1,024 plant association occurrences within 21 4 natural areas (including 115 NFS Research Natural Areas). Of the 1,566 combinations of association within ecological sections, 28 percent require additional data for further analysis; 8, 40, and 12 percent, respectively, are ranked from high to low conservation priority; 13 percent are fully represented. Patterns in natural area needs vary between ecological section. The result provides an operational prioritization of Research Natural Area needs at landscape and subregional scales. Objective ranking criteria provide clear accounting of priority assignments that are easily updated to reflect changing information or conditions. Keywords: ecological reference area, biological diversity, conservation planning, plant community ecology The Author Steven K. Rust is Ecologist for the ldaho Department of Fish and Game, Conservation Data Center, Boise, ID. He holds bachelors degrees in environmental studies and botany from The Evergreen State College and University of Washington. He received an M.S. degree from the College of Forest Resources, University of Washington, in ecosystems analysis. Prior to joining the Conservation Data Center in 1994, he worked as a Botanist and Plant Ecologist for the National Park Service, Bureau of Land Management, and USDA Forest Service. You may order additional copies of this publication by sending your mailing information in label form through one of the following media. Please send the publication title and number. Telephone (970) 498-1 392 E-mail rschneidert2fs.fed.u~ FAX (970) 498-1396 Mailing Address Publications Distribution Rocky Mountain Research Station 240 West Prospect Road Fort Collins, CO 80526-2098 Cover photo: View west of meadow vegetation within Smiley Mountain RNA, located in the Pioneer Mountains of east-central Idaho. Photo by Cate Brigden, September 3, 1995. Representativeness Assessment of Research Natural Areas on National Forest System Lands in ldaho Steven K. Rust Contents Introduction ....................................................................................................... Methods .............................................................................................................. Study Area ...................................................................................................... Synecological Perspective and Nomenclature ............................................... Estimation of Natural Distribution and Abundance .......................................... Selection of Representative Element Occurrences ........................................ Assignment of Priorities for Filling Gaps in the Natural Area Network ............ Results and Discussion .................................................................................... Northwest Basin and Range Section .............................................................. Yellowstone Highlands Section ....................................................................... Overthrust Mountains Section ........................................................................ ldaho Batholith Section ................................................................................... Beaverhead Mountains Section ...................................................................... Challis Volcanics Section ............................................................................... Blue Mountains Section .................................................................................. Okanagon Highlands Section .......................................................................... Flathead Valley Section .................................................................................. Bitterroot Mountains Section .......................................................................... Conclusions ....................................................................................................... References ......................................................................................................... Table 1. Plant associations and community types known or expected to occur in Idaho listed by National Vegetation Classification subclass ................. Table 2 . Assessment summary by ecological section listed by National Vegetation Classification Subclass ....................................................... Appendix A . Research Natural Areas on National Forest System lands in ldaho ...................................................................................................... Appendix B . Research Natural Areas on National Forest System lands in ldaho listed by lead Forest and Ranger District with proposed and established Research Natural Areas ................................................................... Appendix C . Natural areas considered in the representativeness assessment listed alphabetically by the State in which they occur .................... Appendix D. Plant community elements that occur in Research Natural Areas on National Forest System lands in ldaho listed alphabetically with the total area of occurrence and by Research Natural Area, with the total area of occurrence ................................................................................ occurrences, which meet minimum criteria, listed for each plant association or communitv tv~ewith the size of the occurrence ......................... Acknowledgments Support for this study was provided by USDA Forest Service, Northern Region, Intermoun- tain Region, and Rocky Mountain Research Station (formerly Intermountain Research Station) through a cooperative agreement between the Rl/R4/1NT Natural Areas Program and ldaho Department of Fish and Game. Thanks to Bob Moseley, Michael Mancuso, Mabel Jankovsky-Jones, Pat Green, and Art Zackfor help in compiling information that contributed to the study or for reviewing early drafts. Linda Williams, Julie Kaltenecker, Pam Peterson, Andrew Pitner, Juanita Lichthardt, and George Stephens helped maintain data base records on natural areas in Idaho. Thanks to Marion Reid and Rex Crawford for assistance with tables presented in Reid and others 1995. Bob Keane and Jim Menakis provided assistance with spatial data used in the study. Margaret Beer, Joel Peterson, Mary Neighbours, Jack McMillen, and Kathy Ahlenslager helped with information on natural areas in adjacent States. Terry Vernholm completed final edits on the document. Many thanks to Alma Winward and Angela Evenden for their continuing support of natural areas. I recognize and thank Chuck Wellner for his leadership in natural area identification and conservation. Chuck's long and dedicated service to natural areas in ldaho is a legacy of natural heritage conservation in the Northwest. I thank Melinda Moeur and Dennis Ferguson for their support in publishing this document. Introduction ecosystem composition, structure, and functionu (Christensen and others 1996).Implementation of adaptive Biological diversity encompasses all levels of natural management strategies is a focal component of ecosystem variation from molecules to species to landscapes. With the management. In adaptive management, which involves a complexity of biological and physical components and repetitive, ordered cycle of planning, implementation,moni- variability on spacial and temporal scales, biological diver- toring, and evaluation, the hypothetical, iterative nature of sity is difficult to understand or characterize unless it is resource management is recognized (Christensen and oth- partitioned into components of repeated patterns (Huston ers 1996; Forest Ecosystem Management Assessment Team 1994). This is a conceptual objective of the coarse-filter/ 1993).A principal tenet of ecosystem management is that fine-filter approach to conservation of biological diversity. biological diversity, productivity, and sustainability may The idea is that protected areas containing representative be maintained or enhanced by managing lands within the examples of all communities (or ecosystems) will protect historic range of variability (Swanson and others 1994). viable populations of most species, most biotic interac- Research Natural Areas provide the experimental