Burke: Equisetum palustre vs. Equisetum variegatum

	Equisetum palustre	Equisetum variegatum
	marsh horsetail	variegated horsetail, northern scouring-rush
Habit	Rhizomatous annual, the stems not dimorphic, 2-8 dm. tall, with 5 to 10 deep grooves, the ridges smooth; stomates in a single, broad band in each furrow; central cavity less than 1/3 the diameter of the stem; sheathes green, 5-10 mm. long, with persistent teeth 3-7 mm. long, black or dark brown with broad, pale, papery margins.	Stems evergreen, perennial, from black, smooth rhizomes, all alike, ascending or erect, 1-3 dm. tall and 1-2 mm. thick, branched near the base; stems 5-to 12-ridged, the ridges very shallow; stomates in 2 rows in each furrow, sunken below the level of the epidermis; central cavity 1/4 to 1/3 the diameter of the stem; sheaths 2-4 mm. long, green with black tips, the teeth with conspicuous white margins, abruptly contracted to a hair-like tip.
Leaves	Branches few and irregular to many and whorled, 5- to 6-angled, simple.	None.
Spores	Cones pedunculate, blunt, deciduous.	Cones small, up to 1 cm. long, sharp pointed.

	Equisetum palustre	Equisetum variegatum
Habitat	Streambanks, wet meadows, and marshes, from the lowlands to moderate elevations in the mountains.	Wet places, from sea level to alpine.
Distribution	Occurring on both sides of the Cascades crest in Washington; Alaska to California, east across the northern U.S. and Canada to the Atlantic Coast; circumboreal. [WildflowerSearch map] [BONAP county map]	Occurring chiefly east of the Cascades crest in Washington; Alaska to Oregon, east across southern Canada and the northern third of the United States to the Atlantic Coast; circumboreal. [WildflowerSearch map] [BONAP county map]
Origin	Native	Native
Conservation status	Not of concern	Not of concern
Sibling taxa	E. arvense, E. ×ferrissii, E. fluviatile, E. hyemale, E. laevigatum, E. ×litorale, E. ×mackaii, E. ×nelsonii, E. scirpoides, E. sylvaticum, E. telmateia, E. variegatum	E. arvense, E. ×ferrissii, E. fluviatile, E. hyemale, E. laevigatum, E. ×litorale, E. ×mackaii, E. ×nelsonii, E. palustre, E. scirpoides, E. sylvaticum, E. telmateia
Subordinate taxa		E. variegatum ssp. alaskanum, E. variegatum ssp. variegatum
Web links	Local floras: BC, CA, OR, WA Local Web sites: CalFlora, CalPhotos, Flora NW, PNW Herbaria WildflowerSearch iNaturalist (observations) USDA Plants Database LBJ Wildflower Center SEINet Plants of the World Online Encyclopedia of Life Wikipedia Google Image Search	Local floras: BC, OR, WA Local Web sites: Flora NW, PNW Herbaria WildflowerSearch iNaturalist (observations) USDA Plants Database LBJ Wildflower Center SEINet Plants of the World Online Encyclopedia of Life Wikipedia Google Image Search

Equisetum variegatum

marsh horsetail

variegated horsetail, northern scouring-rush

Habit

Rhizomatous annual, the stems not dimorphic, 2-8 dm. tall, with 5 to 10 deep grooves, the ridges smooth; stomates in a single, broad band in each furrow; central cavity less than 1/3 the diameter of the stem; sheathes green, 5-10 mm. long, with persistent teeth 3-7 mm. long, black or dark brown with broad, pale, papery margins.

Stems evergreen, perennial, from black, smooth rhizomes, all alike, ascending or erect, 1-3 dm. tall and 1-2 mm. thick, branched near the base; stems 5-to 12-ridged, the ridges very shallow; stomates in 2 rows in each furrow, sunken below the level of the epidermis; central cavity 1/4 to 1/3 the diameter of the stem; sheaths 2-4 mm. long, green with black tips, the teeth with conspicuous white margins, abruptly contracted to a hair-like tip.

Leaves

Branches few and irregular to many and whorled, 5- to 6-angled, simple.

None.

Spores

Cones pedunculate, blunt, deciduous.

Cones small, up to 1 cm. long, sharp pointed.

Equisetum palustre

Equisetum variegatum

Habitat

Streambanks, wet meadows, and marshes, from the lowlands to moderate elevations in the mountains.

Wet places, from sea level to alpine.

Distribution

Occurring on both sides of the Cascades crest in Washington; Alaska to California, east across the northern U.S. and Canada to the Atlantic Coast; circumboreal.

[WildflowerSearch map]

[BONAP county map]

Occurring chiefly east of the Cascades crest in Washington; Alaska to Oregon, east across southern Canada and the northern third of the United States to the Atlantic Coast; circumboreal.

[WildflowerSearch map]

[BONAP county map]

Origin

Native

Conservation status

Not of concern

Sibling taxa