Redroot Flatsedge, Red-root Flatsedge, Red-rooted Flatsedge
Cyperus erythrorhizos
Synonyms: Cyperus cupreus, Cyperus erythrorhizos var. cupreus, Cyperus halei, Cyperus occidentalis, Cyperus washingtonensis
Redroot flatsedge as seen on a muddy bank along a slough that runs northeast from the Sandy River to the banks of the Columbia River at the east side of the Sandy River delta, Troutdale, Washington.........September 29, 2012.
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Additional images of redroot flatsedge as seen on a muddy bank along a slough that runs northeast from the Sandy River to the banks of the Columbia River at the east side of the Sandy River delta, Troutdale, Washington.......September 29, 2012.
What appears to be redroot flatsedge as seen on mudflats on the Columbia River shoreline along the Washougal Dike, Columbia River Gorge.......August 31, 2015.
Paul Slichter