[The Horsetail Family in the Columbia River Gorge of Oregon and Washington]

The photo above shows the round-tipped cone of smooth scouring-rush as seen in moist soils along an irrigation canal along the Willard Springs Trail at Conboy Lake National Wildlife Refuge.........August 17, 2007. This species is both emergent (growing in water up to 50 cm or more in depth, or can be found on moist banks or floating vegetation rafts immediately adjacent to water.

The photo above shows the black-tipped teeth atop a sheath of a water horsetail as seen in moist soils along an irrigation canal along the Willard Springs Trail at Conboy Lake National Wildlife Refuge.........August 17, 2007. The sheaths at each joint do not have a black band below the teeth as in some other horsetails. Note also that the number of teeth is the same as the number of ribs at the sheath.

The photo above shows the whorls of branches arising from the upper joints of water horestail as seen in a canal alongside the Willard Springs Trail in Conboy Lake NWR.........August 17, 2007. Note that the teeth at the top of each joint are black, and there is no lower black band at the joint.