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• * *DRAFT * * 3 Habitat Bradshaw's lomatium is endemic to the central and southern portions of the Willamette Valley in western Oregon (USFWS 1993), and near LaCamas Lake, Washington. Occurrence has been documented in three distinct habitat types: (1) shallow, alluvial soils near the Santiam River; (2) seasonally saturated or flooded prairies along creeks and streams in the southern Willamette Valley; and (3) wet prairie in the vicinity of LaCamas Lake, Washington. Most populations are found in seasonal wet prairie habitat in the southern Willamette Valley, particularly near Eugene. Bradshaw's lomatium occurs in the wet prairies dominated by tufted - hairgrass (Deschampsia caespitosa). The Deschampsia community is a tall grass prairie type, typically found in the low, flat, bottomlands of the Willamette Valley (Franklin and Dyrness 1973). Less that one percent of these native wet prairies have survived since Euroamerican settlement (Alverson 1994). These areas usually have standing water from October to May. The soils are uniformly heavy clay with little rock, sand, or gravel present (Kagan 1980). Native vascular plants associated with this habitat type are listed in Appendix 1. Many introduced plants are also common in the wet prairie habitat. Common introduced species found at Willow Creek Preserve, a Deschampsia caespitosa grassland in west Eugene, are also listed in Appendix 1. Other sensitive plant and animal species often found with Bradshaw's lomatium include: white - topped aster (Aster curtus), Willamette daisy (Erigeron decumbens var. decumbens), shaggy horkelia ( Horkelia congesta ssp. congesta), Kincaid's lupine (Lupinus sulphureus ssp. kincaidii), Fender's blue butterfly (Icaricia icarioides fenderi), and northwestern pond turtle (Clemmys marmorata marmorata). Life History Bradshaw's lomatium is an herbaceous plant from a perennial taproot. It reproduces by seed only, without vegetative spread. The peak blooming period is usually the last week in April through the first week in May. A diverse assemblage of insects, especially solitary bees and flies, visit the flowers (Kaye 1992, Kaye and Kirkland 1994). The species does not self - pollinate, but depends on these insects for pollen transfer. Status Seventeen distinct populations of Bradshaw's lomatium currently occur in the Willamette Valley and southwest Washington (Parenti et al. 1993; Gisler 1994; St. Hilare 1994; Robinson 1995). It is estimated that less than 0.1 percent of the historic populations of Bradshaw's lomatium remain (Parenti et al. 1993).