Sisyrinchium sarmentosum (pale blue-eyed grass or mountain pale blue-eyed grass)
Sisyrinchium sarmentosum (pale blue-eyed grass or mountain pale blue-eyed grass) is a small member of the Iridaceae family. S. sarmentosum was first described in 1895 by Wilhelm Sukdorf from the Gifford Pinchot National Forest. S. sarmentosum is a narrow endemic known only from south central Washington (Skamania and Klickitat Counties) and north central Oregon (Clackamas and Marion Counties). Only twenty-two populations are presently known; for this reason, S. sarmentosum is a Forest Service Region 6 Sensitive Species, and a Bureau of Land Management Bureau Sensitive Species in both Oregon and Washington. The majority of S. sarmentosum populations and individuals occur on national forest land on Gifford Pinchot and Mt. Hood National Forests.
Many S. sarmentosum populations are at risk of damage or extirpation through habitat loss and habitat fragmentation, livestock grazing, hybridization with closely related S. idahoense, woody plant succession in meadow habitat, competition from invasive plants, and motor vehicle and recreation impacts to sites.
In response to these recognized threats, a number of research and restoration efforts have been conducted, or are ongoing:
- Andrea Raven, Conservation Biologist from the Berry Botanic Garden conducted a grazing exclosure study over four field seasons (1997-2000) at Cave Creek, Gifford Pinchot National Forest. She found that grazing by cattle removes a substantial portion of S. sarmentosum vegetation, including flowers and seeds, compromising the ability of individuals to grow and sexually reproduce. This important research is now being used to help craft better, more sustainable grazing management across the range of the species.
- Recreational vehicle use in S. sarmentosum’s fragile meadow habitat was observed to cause the destruction of plants during 2004-2005. In response, a boulder placement project will be implemented in 2006, which will prevent vehicles from entering the largest and most genetically diverse site for this species, which is also the type locality. This important population will now be protected from damage by recreational vehicles.
- Seed collections from eight S. sarmentosum populations on the Gifford Pinchot and Mt. Hood National Forests were made during summer 2004 and 2005, and are now banked at Berry Botanic Garden. Seed banking provides long-term insurance against population extirpation, and provides opportunities for restoration.
- Houndstongue, tansy ragwort, Canada thistle and bull thistle were hand pulled/clipped during 2004, 2005 (and continuing treatment is planned), at two populations of S. sarmentosum on the Gifford Pinchot National Forest, which comprise 82-90% of all individuals.
- During 2000 and 2003, genetic analysis was performed to determine levels of genetic diversity within and between populations. This data is being utilized to help inform population management.
- During 2005-2006, the Berry Botanic Garden, in partnership with the Gifford Pinchot and Mt. Hood National Forests, is developing a hybrid index for S. sarmentosum, built with morphological and genetic data. This project will be completed by the end of fiscal year 2006, and will help botanists identify pure vs. hybridized populations.