Family
Rosaceae
Plant description
Long-lived perennial with a low, spreading growth form, 5-15 cm long. Most leaves are basal and compound with 5-15 pairs of overlapping leaflets which are further divided into 3 to 5 segments each. Leaves are densely hairy but not glandular. Inflorescences are erect before flowering but then become prostrate. Flowers are small with white to pale yellow petals 0.8 to 1.5 mm long.
Distinguishing characteristics
The non-glandular leaves and paler flowers separate this species from other closely related ivesias. The other variety in this species, Ivesia rhypara var. shellyi, is slightly smaller and grows in depressions on large boulders. Ivesia rhypara var. rhypara grows in shallow, ashy soils.
Habitat
Populations are found on either light colored ash-tuff or on outcrops of volcanic ash deposited with riverbed gravels. Habitat is very dry and relatively barren with no canopy cover. Common associated species include Gilia congesta, Sitanion hystrix, Scutellaria nana, and Eriophyllum lanatum.
Range
Southeast Oregon and northern Nevada
Oregon counties
Lake, Malheur
Federal status
Species of Concern
Threats
Off-road vehicles, grazing, mining
Did you know?
The species and varietal name, rhypara, translates to dirty or grimy in Greek. This not only describes the appearance of the plant in its native habitat but also was chosen to honor the co-discoverer of the plant, James W. Grimes.
References
Amsberry, K., M. Carlson, and R.J. Meinke. 2002. Range-wide population evaluation of the scattered disjunct Ivesia rhypara var. rhypara. Native Plant Conservation Program, Oregon Department of Agriculture, Salem, Oregon.
Center for Plant Conservation. 2007. Online plant profile of Ivesia rhypara var. rhypara. http://www.centerforplantconservation.org/ASP/CPC_ViewProfile.asp?CPCNum=9680. Accessed July 25, 2007.
Ertter, B. 1989. Revisionary studies in Ivesia (Rosaceae: Potentilleae). Systematic Botany 14:231-244.
Ertter, B.J. and J.L. Reveal. 1977. A new species of Ivesia (Rosaceae) from southeastern Oregon. Madrono 24:224-227.
Kaye, T., B. Meinke, S. Kephart, and J. Mellor. 1991. Systematic study, monitoring program, and inventory of Ivesia rhypara. Report for Bureau of Land Management (Lakeview District). Native Plant Conservation Program, Oregon Department of Agriculture, Salem, Oregon.
ORNHIC (Oregon Natural Heritage Information Center). 2003. Oregon Natural Heritage Information Center Database. Oregon Natural Heritage Information Center, Portland, Oregon.
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