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Equisetum telmatiea

Giant Horsetail

At a Glance: More robust and larger than common horsetail. Sheaths around its sterile stems have 14-18 teeth.

Height: 3-7.5 (10) feet tall; 1-2.3 (3) meters tall.
Growth Form: Fern.
Stems: Proportionately stouter, and always erect - never sprawling weakly. Fertile stems appear before sterile stems, unbranched, to 60 cm (2 ft) tall; spore cone at tip. New shoots emerge mid-February to early May.
Leaves: Reduced to tiny scales that are fused into 20-30 sheaths at stem nodes. Dense whorls of branches (often mistaken for leaves) form at stem nodes; shape: sterile stems branched, hollow; size: sheaths to 2.5 cm (1 in) long; color: green.
Flowers: Horsetails reproduce by spores, and do not have flowers; green spores are produced in flesh-colored cone at tip of fertile stem.
Flowering Period: none.
Fruits: blunt-tipped cones; size: cones to 10 cm (4 in) long; color: whitish to flesh colored (become brownish just before withering).


Photo © Starflower Foundation

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. wet moist dry Wetland Indicator Status: FACW (facultative wetland)	Below 1000 meters. low elevation mid elevation sub-alpine high elevation

Soil Preferences
sandy soils gravelly soils clay soils muddy soils peaty soils	well drained soils shallow soils deep soils acidic soils basic soils	humic soils nutrient rich soils nutrient poor soils mineral soils organic soils

Habitat Preferences
Aquatic and Wetland: Ponds or lakes Shallow pools Sloughs Swales or wet ditches Seasonally inundated areas Marshes or swamps Aquatic bed wetlands Emergent wetlands Scrub-shrub wetlands Forested wetlands Bogs, fens Seeps, springs Shorelines and Riparian: Lake shores Bog margins Streams or rivers Stream or river banks Riparian corridors River bars Floodplains Bottomlands Alluvial areas	Saltwater Areas: In or near saltwater Mud flats Tidal areas Estuaries Saltmarshes Brackish water Seashores Coastal dunes or beaches Rocky or Gravelly Areas: Coastal bluffs Cliffs Rocky slopes Outcrops Crevices Glacial outwash Gullies Slide areas Sub-alpine and Alpine: Heaths Snow beds Tundra Avalanche tracks	Forests and Thickets: Forests and woods Open forests Coniferous forests Old growth forests Deciduous forests Mixed forests Nurse logs Forest edges, openings, or clearings Thickets Meadows and Fields: Pastures or fields Meadows or grassy areas Mossy areas Disturbed Areas: Roadsides Trailsides Logged sites Burned areas Disturbed sites

Wildlife Value

(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.

Suggested References

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 Starflower Foundation Image Herbarium. All photographs © Starflower Foundation unless otherwise noted.