National Park Service U.S. Department of the Interior Natural Resource Stewardship and Science Conservation Assessment for Parish’s Daisy (Erigeron parishii, Asteraceae) in Joshua Tree National Park Natural Resource Report NPS/JOTR/NRR—2014/887 ON THE COVER Parish’s daisy in full flower on April 26, 2006, Long Canyon, on the western edge of Joshua Tree National Park, San Bernardino County, California. Photograph by: Tasha La Doux, Joshua Tree National Park Conservation Assessment for Parish’s Daisy (Erigeron parishii, Asteraceae) in Joshua Tree National Park Natural Resource Report NPS/JOTR/NRR—2014/887 Naomi S. Fraga, Linda Prince Rancho Santa Ana Botanic Garden 1500 N. College Ave. Claremont, CA 91711-3157 Tasha La Doux, Mitzi Harding, and Josh Hoines Joshua Tree National Park 74485 National Park Drive Twentynine Palms, CA 92277 November 2014 U.S. Department of the Interior National Park Service Natural Resource Stewardship and Science Fort Collins, Colorado The National Park Service, Natural Resource Stewardship and Science office in Fort Collins, Colorado, publishes a range of reports that address natural resource topics. These reports are of interest and applicability to a broad audience in the National Park Service and others in natural resource management, including scientists, conservation and environmental constituencies, and the public. The Natural Resource Report Series is used to disseminate high-priority, current natural resource management information with managerial application. The series targets a general, diverse audience, and may contain NPS policy considerations or address sensitive issues of management applicability. All manuscripts in the series receive the appropriate level of peer review to ensure that the information is scientifically credible, technically accurate, appropriately written for the intended audience, and designed and published in a professional manner. This report received formal peer review by subject-matter experts who were not directly involved in the collection, analysis, or reporting of the data, and whose background and expertise put them on par technically and scientifically with the authors of the information. Views, statements, findings, conclusions, recommendations, and data in this report do not necessarily reflect views and policies of the National Park Service, U.S. Department of the Interior. Mention of trade names or commercial products does not constitute endorsement or recommendation for use by the U.S. Government. This report is available in digital format from the Joshua Tree National Park website (http://www.nps.gov/jotr/naturescience/rare_plants.htm) and the Natural Resource Publications Management website (http://www.nature.nps.gov/publications/nrpm/). To receive this report in a format optimized for screen readers, please email [email protected]. Please cite this publication as: Fraga, N., T. La Doux, L. Prince, M. Harding, and J. Hoines. 2014. Conservation assessment for Parish’s daisy (Erigeron parishii, Asteraceae) in Joshua Tree National Park. Natural Resource Report NPS/JOTR/NRR—2014/887. National Park Service, Fort Collins, Colorado. NPS 156/127341, November 2014 ii Contents Page Figures.................................................................................................................................................... v Tables ..................................................................................................................................................... v Appendices ............................................................................................................................................ vi Summary .............................................................................................................................................. vii Acknowledgments ................................................................................................................................. ix Acronyms and Initialisms ..................................................................................................................... ix Contacts ................................................................................................................................................. ix Introduction ............................................................................................................................................ 1 Scope and Purpose .......................................................................................................................... 1 Background..................................................................................................................................... 1 Species Description ................................................................................................................................ 2 Taxonomic History ................................................................................................................................ 7 Biology and Ecology .............................................................................................................................. 8 Life History .................................................................................................................................... 8 Reproductive Biology ..................................................................................................................... 8 Genetics .......................................................................................................................................... 9 Habitat .......................................................................................................................................... 13 Climate ......................................................................................................................................... 14 Vegetation and Associated species ............................................................................................... 15 Distribution and Abundance ................................................................................................................ 17 Status of Populations ............................................................................................................................ 19 Threats .................................................................................................................................................. 21 Conservation Status ............................................................................................................................. 23 Ex-situ Conservation: Seed Bank Holdings ......................................................................................... 23 Future Recommendations .................................................................................................................... 25 Research ....................................................................................................................................... 25 Population-level and phylogenetic studies .............................................................................. 25 Life-history and reproductive biology studies ......................................................................... 25 iii Contents (continued) Page Park Management ......................................................................................................................... 26 Field Surveys and Habitat Modeling ....................................................................................... 26 Annual Monitoring .................................................................................................................. 26 Protection ................................................................................................................................. 27 Literature Cited .................................................................................................................................... 78 iv Figures Page Figure 1. Map showing general location of Joshua Tree National Park (JOTR) in southern California and the global distributions for the two federally listed species known to JOTR: Astragalus tricarinatus and Erigeron parishii ....................................................................... 3 Figure 2. Map showing all known occurrences of Erigeron parishii (blue circles) and the land ownership for occupied habitat. ..................................................................................................... 4 Figure 3. Erigeron parishii in flower, showing light purple ray florets, yellow disk florets, and gray herbage. ....................................................................................................................... 5 Figure 4. Habit of Erigeron parishii showing herbaceous stems from the previous growing season. ...................................................................................................................................... 5 Figure 5. Geologic map from southern California (USGS 2009), showing substrates that Erigeron parishii occurs on throughout its range, including within Joshua Tree National Park. ..................................................................................................................................................... 11 Figure 6. Detailed geologic map of Erigeron parishii locations (blue circles) within Joshua Tree National Park. .................................................................................................................