[The Horsetail Family in the Columbia River Gorge of Oregon and Washington]
Common Horsetail, Field Horsetail
Equisetum arvense
Synonym: Equisetum arvense var. boreale
Common horsetail as seen on mud flats along the Columbia River shoreline at the east side of the Sandy River Delta, Troutdale, Oregon...........September 8, 2012.
Field horsetail emerging from spring foliage along the Eagle Creek Trail, Columbia River Gorge..........April 11, 2013.
Paul Slichter