At a Glance: More robust and larger than common horsetail. Sheaths around its sterile stems have 14-18 teeth.
|Sun/Shade Tolerance||Hydrology||Elevation Range||
full sun > 80%
mostly sunny 60%-80%
partial sun and shade 40%- 60%
mostly shady 60%-80%
full shade > 80%
|common in areas with high water tables.
Wetland Indicator Status:
FACW (facultative wetland)
Below 1000 meters.
well drained soils
nutrient rich soils
nutrient poor soils
Aquatic and Wetland:
Ponds or lakes
Swales or wet ditches
Seasonally inundated areas
Marshes or swamps
Aquatic bed wetlands
Seeps, springsShorelines and Riparian:
Streams or rivers
Stream or river banks
In or near saltwater
Coastal dunes or beachesRocky or Gravelly Areas:
Slide areasSub-alpine and Alpine:
Forests and Thickets:
Forests and woods
Old growth forests
Forest edges, openings, or clearings
ThicketsMeadows and Fields:
Pastures or fields
Meadows or grassy areas
Mossy areasDisturbed Areas:
|(data not available)|
|Ethnobotanical Uses and Other Facts||
Food Uses: Preferred horsetail for native groups of the coast. The young spore bearing and vegetative shoots of the giant horsetail were an important springtime vegetable of some Coast Salish and Nuu-chah-nulth peoples. They were picked when young and eaten raw, sometimes with oil, after the papery sheaths head been removed.
Toxicity: Poisonous to horses and livestock. Probably poisonous to humans also, if eaten in large quantities..
Landscape Uses: Good for stabilizing or restoring disturbed or degraded (including logged or burned) areas, for erosion and slope control, for wildlife food or cover, etc. May be less suitable for garden use.
Ecological Importance: Often forms dense colonies.
Name Info: The epithet Temateia is an old name that means "of muddy water or marshes." Called Giant Horsetail because of its size.
Interesting Facts: Horsetails are a very ancient group of plants that grew to the size of trees when dinosaurs roamed the earth.
- Cooke, S.S. A Field Guide to the Common Wetland Plants of Western Washington and Northwetern Oregon. Seattle Audubon Society and Washington Native Plant Society. Page 383.
- Guard, B.J. 1995. Wetland Plants of Oregon & Washington. Lone Pine Publishing. Page 195.
- Hickman, J.C., ed. 1993. The Jepson Manual: Higher Plants of California. University of California Press. Page 95.
- Hitchcock, C.L., A. Cronquist. 1973. Vascular Plants of the Pacific Northwest. University of Washington Press. Page 44.
- Jacobson A.L. 2001. Wild Plants of Greater Seattle. Published by author. Page 372.
- Lyons, C., W. Merilees. Trees and Shrubs to Know in Washington and British Columbia. Lone Pine Publishing. Page 344.
- Pojar, J., A. Mackinnon. 1994. Plants of the Pacific Northwest Coast. Lone Pine Publishing. Page 431.
- Whitson, T.D., ed. 2001. Weeds of the West. University of Wyoming. Page 306.
The landscaping and restoration information provided on this page is taken from the Starflower Foundation Image Herbarium. All photographs © Starflower Foundation unless otherwise noted.