Kingdom: Plantae

Phylum: Equisetophyta -- horsetails

Class: Equisetopsida

Order: Equisetales

Family: Equisetaceae -- horsetail

Genus: Equisetum

Common Name: common scouringrush, scouringrush horsetail

Species Code: EQHY, EQHYA

Origin: The species is circumboreal, ssp. affine is native to moist and wet places over much of North America.

Rare: no

Form: perennial from a rhizome; stems monomorphic, hollow, photosynthetic, evergreen, usually unbranched, 20-150 cm tall.

Duration: perennial

Longevity: long

Habitat Type: wetland

Wetland Indicator Status: FACW

Leaves: small, scale-like and non-photosynthetic, borne in whorls sheathing the stem.

Mature height: 8-60 inches

Flowers: Equisetum species do not have flowers in the traditional sense. Sexual reproduction is by spores which germinate to form a small gametophyte generation only a few millimeters across. The gametophytes are unisexual and fertilization requires a film of water between the male and female gametophytes. The sporophyte generation arises from the fertilized archegonium in the female gametophyte.

Fruit: sporangia clustered together to form a cone (strobolis) at the tip of the stem, strobolis borne on a short peduncle, 1-2.5 cm long, apiculate, ovate to oblong; spores spherical and green.

Characteristics:
Reproduces both sexually by spores and vegetatively by rhizomes.
Can hybridize with Equisetum laevigatum, producing Equisetum x ferrissii, which is sterile but can spread vegetatively.
Prefers wet sites but sometimes found on upland sites.
n=108 (Hitchcock et al 1969, Flora of North American Editorial Committee 1993).
Spores are windborne.
Native peoples used the plants medicinally.
Poisonous to livestock.

Sun requirement: full

Soil moisture: moist to wet

Hazards: Poisonous to livestock.

Transplant time: spring or fall

Planting duration: long

Seed comments: reproduces by spores

Herbaria: Specimen data and digital resources from The Consortium of Pacific Northwest Herbaria

Key words: perennial wetland horsetail

Propagation:
Reproduces both sexually by spores and vegetatively by rhizomes. Can be propagated from rhizomes.

Notes: Sometimes found on what appear to be dry hillsides.

References:
Flora of North America Editorial Committee, eds. 1993+. Flora of North America North of Mexico. 7+ vols. New York and Oxford. Oxford University Press. Online at http://www.fna.org/FNA/

Hitchcock, C. Leo, Arthur Cronquist, Marion Ownbey, and J.W. Thompson. 1969. Vascular Plants of the Pacific Northwest. University of Washington Press. Seattle, WA. 5 vol.

USDA NRCS. 2009. The PLANTS Database (http://plants.usda.gov, 31 August 2009). National Plant Data Center, Baton Rouge, LA 70874-4490 USA.

Links:
Plant Profile from the USDA PLANTS Database
Species description from Flora of North America
Species information from the University of Washington Herbarium