[Horsetails: The Genus Equisetum East of the Cascade Mountains of Oregon and Washington]
Common Scouring-rush, Common Scouring-rush, Scouring-rush Horsetail, Dutch Rush, Prairie Scouring-rush

Equisetum hyemale var. affine

Synonyms: Equisetum affine, Equisetum hyemale ssp. affine, Equisetum hyemale var. californicum, Equisetum hyemale var. pseudohyemale, Equisetum hyemale var. robustum, Equisetum praealtum, Equisetum robustum, Hippochaete hyemalis, Hippochaete hemalis ssp. affinis

Common Scouring-rush, Common Scouring-rush, Scouring-rush Horsetail, Dutch Rush, Prairie Scouring-rush: Equisetum hyemale var. affine (Synonyms: Equisetum affine, Equisetum hyemale ssp. affine, Equisetum hyemale var. californicum, Equisetum hyemale var. pseudohyemale, Equisetum hyemale var. robustum, Equisetum praealtum, Equisetum robustum, Hippochaete hyemalis, Hippochaete hemalis ssp. affinis)

Common scouring-rush as seen along Oregon Highway 218 about a mile south of Shaniko, OR...............May 14, 2010.
Paul Slichter