CONSERVATION ASSESSMENT OF SENSITIVE MOONWORTS (OPHIOGLOSSACEAE; BOTRYCHIUM SUBGENUS BOTRYCHIUM) ON THE KOOTENAI NATIONAL FOREST Prepared by: Jim Vanderhorst Montana Natural Heritage Program State Library P.O. Box 201800 1515 East Sixth Avenue Helena, Montana 59620-1800 Prepared for: Kootenai National Forest Supervisors Office 506 U.S. Highway 2 West Libby, Montana 59923 Agreement No. 11011454002 February 1997 © 1997 Montana Natural Heritage Program This document should be cited as follows: J. Vanderhorst. 1997. Conservation assessment of sensitive moonworts (Botrychium subgenus Botrychium) on the Kootenai National Forest. Montana Natural Heritage Program, Helena, MT. 82 pp. plus appendices. i SUMMARY Over one hundred occurrences of six sensitive or proposed sensitive Botrychium species are documented on the Kootenai National Forest. These include most of the largest known populations of B. minganense and B. montanum in the state and a few large populations of B. crenulatum. There are also a few small occurrences of three extremely rare species, B. ascendens, B. paradoxum, and B. pedunculosum. The sensitive Botrychium species occupy a variety of moist habitats distributed across the glaciated landscapes of Forest; mostly western red cedar and western hemlock habitat types in the western part and mostly deciduous wetland habitat types in the eastern part. Primary potential threats to populations include direct impacts of logging and road building to upland occurrences and indirect and cumulative effects of these activities to lowland occurrences. USFS Region 1 sensitive status is proposed for B. pedunculosum which was found for the first time in the Region on the Forest in 1996, and current sensitive status is recommended retained for the other five species. ACKNOWLEDGEMENTS Many Kootenai National Forest employees shared their data and knowledge, helped locate and survey moonwort populations, and assisted in many other ways. I give special thanks to Mike Arvidson, Terese Bielak, Annie Deuker, Leslie Ferguson, Kara Hungate, Lou Kuennen, Dan Leavell, Roy Lofts, Mike Lolley, Jon Reny, Toby Spribille, and Jack Triepke. At the Montana Natural Heritage Program special thanks go to Bonnie Heidel for coordination and technical contributions, Cedron Jones for GIS mapping, John Caratti for assistance with ecodata analysis, and Margaret Beer, Anne Dalton, Debbie Dover, and Katie Schletz for data management. Thanks are also extended to Peter Zika and Warren H. Wagner for identifying silhouette and color photocopies of the moonworts, to Larry Evans for identifying associated mushrooms, and to Joe Elliott for identifying associated mosses. This project was made possible through challenge cost-share agreements between the Kootenai National Forest and the Montana Natural Heritage Program. ii TABLE OF CONTENTS INTRODUCTION........................................................................................................................... 1 CLASSIFICATION AND IDENTIFICATION............................................................................... 3 LIFE HISTORY .............................................................................................................................. 5 MYCORRHIZAL RELATIONS..................................................................................................... 6 METHODS...................................................................................................................................... 8 RESULTS AND DISCUSSION Summary statistics............................................................................................................. 11 Genus communities........................................................................................................... 11 Habitat characterization..................................................................................................... 13 Associated mushrooms and mosses .................................................................................. 14 Mycorrhizae and vegetative propagules............................................................................ 15 French Creek monitoring transects.................................................................................... 15 STATUS REVIEWS Botrychium ascendens....................................................................................................... 18 Botrychium crenulatum .................................................................................................... 26 Botrychium minganense ................................................................................................... 36 Botrychium montanum ...................................................................................................... 47 Botrychium paradoxum..................................................................................................... 55 Botrychium pedunculosum ................................................................................................ 63 RECOMMENDATIONS AND CONCLUSION Status recomendations....................................................................................................... 70 Threats to populations ....................................................................................................... 71 Interim management guidelines ........................................................................................ 71 Conclusion......................................................................................................................... 74 LITERATURE CITED.................................................................................................................. 77 APPENDIX A: AREAS AND HABITATS SEARCHED (DELETED) APPENDIX B: ELEMENT OCCURRENCE RECORDS AND MAPS (DELETED) APPENDIX C: ECODATA (DELETED) iii APPENDIX D: FRENCH CREEK MONITORING TRANSECTS (DELETED) iv APPENDIX E: MOONWORT COLLECTION GUIDELINES APPENDIX F: ASSOCIATED FUNGI APPENDIX G: ASSOCIATED MOSSES APPENDIX H: SENSITIVE PLANT SCORING CRITERIA APPENDIX I: PHOTOGRAPHIC SLIDES (DELETED) LIST OF TABLES Table 1: Occurrences of sensitive Botrychium species on the KNF ............................................. 11 Table 2: Moonwort genus communities on the KNF.................................................................... 12 Table 3: Documented habitats of sensitive Botrychium spp. on the KNF .................................... 13 Table 4: Summary of intraseasonal monitoring results at French Creek ...................................... 16 Table 5: Two years monitoring results from French Creek........................................................... 17 Table 6: Current and recommended state ranks and USFS status ................................................ 70 Table 7: "Significant" sensitive Botrychium occurrences on the KNF ......................................... 73 LIST OF FIGURES Figure 1: Distribution of Botrychium ascendens........................................................................... 20 Figure 2: Distribution of Botrychium crenulatum......................................................................... 28 Figure 3: Distribution of Botrychium minganense........................................................................ 39 Figure 4: Distribution of Botrychium montanum .......................................................................... 49 Figure 5: Distribution of Botrychium paradoxum......................................................................... 57 Figure 6: Distribution of Botrychium pedunculosum.................................................................... 65 v INTRODUCTION This report summarizes current knowledge on the distribution, ecology, and conservation status of sensitive species of moonworts (Botrychium spp.) on the Kootenai National Forest (KNF). It is based on information gathered in the field by KNF botanists and myself with information from the literature, from related studies in other states, and from Montana Natural Heritage Program sources. The priorities which were identified for this project were to: • Resolve questions concerning identification, location, and population size and condition of known occurrences of sensitive Botrychium species. • Locate and survey new populations, and evaluate biological factors conditioning the results of fieldwork • Characterize the habitats and microhabitats of each species • Assess conservation status and threats to populations of each species and recommend interim management guidelines. Moonworts are primitive ferns with some of the highest chromosome numbers in the plant kingdom, which are characterized by a simple morphology but an often confounding taxonomy. The sporophyte, the conspicuous spore producing generation of the plant, is a small perennial which arises from a simple underground stem with roots which lack roothairs. The plants generally produce one aboveground leaf, or frond, per year with successive primordia enclosed in a sheath at its base. The frond is divided into two parts which share a common stalk, a usually sterile segment, the trophophore, and a fertile segment, the sporophore. The trophophore is laminar and usually pinnatifid (ternate in B. lanceolatum) and features of its lobing are the primary characters which distinguish the species. The sporophore bears grape-like sporangia where spores are produced. Spores germinate and develop into tiny underground gametophytes which are rarely seen or studied. Both generations of the ferns are associated with mycorrhizal fungi.