|Magnoliopsida (Flowering Plants): Onagraceae
Oregon Fireweed (Epilobium oreganum)
Potential Occurrence: Not Expected to Occur
Photos: Dean Wm. Taylor
Species Description: The Oregon Fireweed is an herb growing 40 cm to 1 m tall from leafy basal shoots with a glabrous and glaucous stem and narrowly lanceolate to narrowly ovate leaves with reddish veins (Hickman 1996). The inflorescence is a sparsely strigose raceme with pink to rose-purple flowers with a four lobed stigma (Hickman 1996). The fruit is a 25 to 45 mm hairy, glandular capsule with papillate ridged seeds (Hickman 1996).
Nomenclature: Epilobium oreganum Greene Onagraceae (USDA 2010)
Synonyms: E. exaltatum, E. glaucum, E. subcaesium (Calflora 2010; IPNI 2005)
Distribution: This species occurs in southwest Oregon and California where it is found in the Klamath Ranges and the outer North Coast Ranges (Hickman 1996).
Historically, it was known from…seven other California Counties, as far south as Mendocino County. Its current California distribution needs further study. (From Kagan et al. 2006)
Life History & Threats: The Oregon Fireweed is a perennial herb blooming from June to September and is threatened by logging, drainage, off road vehicle use, mining, wetland alteration, fire suppression, and grazing (CNPS 2010; NatureServe 2009; Kagan et al. 2006).
Habitat & Habitat Associations:
Aquatic Habitat Types: Habitat for this species is bogs and fens dominated by perennial herbs and low shrubs (CNPS 2010). Occurs almost always under natural conditions in wetlands (Calflora 2010). Open, wet, boggy, serpentine sites and wet gently sloping stream banks, meadows (NatureServe 2009).
Vegetation Types: Habitat for this species is mesic lower montane coniferous forests dominated by open to dense stands of conifers and broadleaved trees in the understory and upper montane coniferous forests with the same dominant trees (CNPS 2010).
Topography and Microclimates: Small streams and ditches (Hickman 1996). River terrace fens (Kagan et al. 2006).
Epilobium oreganum, can tolerate some cover, and therefore may be less affected by encroaching vegetation than some other rare low growing forbs of Darlingtonia wetlands (Kagan et al. 2006). (From NatureServe 2009).
Elevation: 500 to 2240 m (CNPS 2010) (The Study Area ranges from 230 to 710 m).
Geology and Soils: ultramafic or serpentine (USFWS 2006). Strong indicator and broad endemic to serpentine soil; 75 to 84% of occurrences are on ultramafics (Calflora 2010).
Species Associations: The Oregon Fireweed associates with the California Pitcher Plant (Darlingtonia californica) (NatureServe 2009).
Conceptual Basis for GIS Model Development: Potential habitat in the Study Area was mapped as areas:
above 470 m (includes 30 m buffer on known elevational occurrences)
coniferous forests (i.e. Redwood-Douglas or Pacific Douglas Fir vegetation) with a multi-storied canopy
Serpentine soils, while common regionally, are not indicated by the GIS soil data as occurring in the Study Area. Springs and seeps are common throughout the Study Area but are not available in the GIS database
Potential Occurrence in the Galbreath Wildlands Preserve:
Habitat: Oregon Fireweed occurs in wet to mesic ultramafic or serpentine soils in grasslands and coniferous forests. Potential habitat for this species does not occur the Galbreath Wildlands Preserve:
Ultramafic or serpentine soils do not occur in the Preserve. Serpentine soils, while common regionally, are not indicated by the GIS soil data as occurring in the Galbreath Wildlands Preserve. To verify the GIS information, we identified all areas (11 sites) of exposed rocky soils from high-resolution satellite imagery. During site visits to these areas, the only serpentine found were rocks exposed by road maintenance activity at a waterbar.
Appropriate vegetation type (multi-storied coniferous forest) within the known elevational range of the species is very limited.
The species is impacted by logging. The Preserve has a history of logging. Timber harvest plans indicate that both clear cut and selection cut methods were used to harvest Redwood, Douglas Fir, and hardwoods at least between 1988 and 2000.
Documented Occurrences in the Galbreath Wildlands Preserve: Previous species list for the Galbreath Wildlands Preserve did not document this species (SSU Field Station and Nature Preserves 2010).
Nearest Occurrence to the Galbreath Wildlands Preserve: Mendocino County is the southern edge of this species range along the North Coast. This species is known from 5 occurrences in the County (Calflora 2010). The nearest occurrence is approximately 13 miles northeast of the Galbreath Wildlands Preserve in the Upper Russian River watershed (Calflora 2010). Occurrence of this species on the Preserve would constitute the southernmost occurrence of this species on the North Coast (Calfora 2010).
Summary: We anticipate the Oregon Fireweed to be “Not Likely to Occur” because potential habitat does not occur within Preserve boundaries.
Calflora. 2010. Information on California plants for education, research and conservation. Accessed 2010 Jul 4.
California Native Plant Society (CNPS). 2010. Inventory of Rare and Endangered Plants. Online edition, v7-10b. Accessed 2010 Jul 4.
Hickman JC editor. 1996. The Jepson Manual Higher Plants of California. 3rd printing. London: University of California Press, Ltd. 797 p.
International Plant Name Index (IPNI). 2005. . Accessed 2010 Jul 4.
Kagan, J, Hoover L , McRae J, Rolle W, Mousseaux M, Mazzu L, Friedman S. 2006. Conservation Agreement for Hastingsia bvacteosa, H. atrogurpurea, Gentiana setigera, Epilobium oreganum, and Viola primulifolia ssp. occidentalis and serpentine Darlingtonia wetlands and fens from Southwestern Oregon and Northwestern California. U.S. Fish and Wildlife Service.
NatureServe. 2009. NatureServe Explorer: An online encyclopedia of life [web application]. Version 7.1. Accessed 2010 Jul 4.
SSU Field Stations and Nature Preserves. 2010. Galbreath Wildlands Preserve Vascular Plant List. . Accessed 2010 Jun.
Taylor DW. 2004. Epilobium oreganum Grants Pass Willowherb. < http://calphotos.berkeley.edu/cgi-bin/img_query?rel-taxon=contains&where-taxon=Epilobium+oreganum>. Accessed 2011 May 15.
United States Department of Agriculture (USDA). 2010. PLANTS Profile. . Accessed 2011 May 15.
Species Account Description: Linden Schneider