Checklist » Equisetaceae
Equisetaceae[FNA2, HC, HC2](Horsetail Family)
Synonyms:
(none)

Notes: FNA2: "Equisetum occurs in moist places such as riverbanks, lakeshores, roadsides, ditches, seepage areas, meadows, marshes, and wet woodlands. Aerial stems of Equisetum vary considerably in habit and appearance, even on individual plants, because of environmentally induced modifications affecting height and branching. Many taxonomically trivial varieties and forms have been named. For an extended discussion of this, see R.L. Hauke (1966). Four widespread, named hybrids are treated in the key and fully described below.

In species descriptions and in the key, length and width are given for the leaf sheath, excluding the free teeth. If the length and width of flattened sheaths are approximately equal and the sides are straight, the sheath is more or less square in face view, i.e., about as long as broad; if the length is greater than the width and the sides are straight, the sheath is more or less elongate in face view, i.e., longer than broad; if the length is greater than the width and the sides are slightly convex, the sheath is elliptic in face view. Stomates are usually visible at 20× magnification.

Reticulation in Equisetum is summarized in the reticulograms, which show the known and expected hybrids in North America. Most of those in Equisetum subg. Equisetum are still unknown in North America, but they should be sought, especially north of 45° N latitude. According to W.J. Cody and D.M. Britton (1989), E . × font-queri occurs rarely in British Columbia and materials possibly representing E . × arcticum Rothmaler have been taken in the Richardson Mountain region of Mackenzie. R.L. Hauke (1978) cited collections of E . × font-queri from British Columbia and California."

References:

» Hauke, R.L. 1966. A systematic study of Equisetum arvense. Nova Hedwigia 13: 81–109. Hauke, R.L. 1979. Equisetum ramosissimum in North America. Amer. Fern J. 69: 1–5.

Family information last updated 12/22/2008 by David Giblin.

Taxon (native taxa in boldface)
Common Names
# Synonyms
Equisetum arvense L.[FNA2, HC, HC2]
common horsetail, field horsetail
1 synonym
Ferriss' scouring rush
1 synonym
or river horsetail, swamp, water
1 synonym
Equisetum hyemale L.[FNA2, HC, HC2]
scouringrush horsetail , common scouring-rush
0 synonyms
common scouring rush, Dutch rush, prairie scouring rush
3 synonyms
smooth scouring rush
2 synonyms
shore horsetail
0 synonyms
small scouring rush
2 synonyms
Nelson's horsetail
0 synonyms
Equisetum palustre L.[FNA2, HC, HC2]
marsh horsetail
1 synonym
meadow horsetail
0 synonyms
sedgelike horsetail, dwarf scouring rush
0 synonyms
wood horsetail, woodland horsetail
0 synonyms
giant horsetail
0 synonyms
giant horsetail, great horsetail
2 synonyms
variegated horsetail, northern scouring-rush
0 synonyms
Alaskan scouring rush
1 synonym
ssp. variegatum[FNA2, HC2]
variegated horsetail, northern scouring rush
1 synonym