Taxonomy
Family: Equisetaceae
Habitat
Wet thickets, bogs, sandy shores.
Associates
Distribution
Circumboreal, south in North America to PA, IL, MN, and CO.
Morphology
Fertile and sterile stems alike, evergreen, ascending or erect, 10-30 cm, 1-2.5 mm diameter, branched near the base, 5-12 ridged; ridges shallowly furrowed and with 2 rows of siliceous tubercles; central cavity a quarter to a third the diameter of the stem, stomates in 2 rows in each main furrow; sheaths slightly flared apically, green, with a blackish apical band; sheath teeth 1-2 mm with a blackish, 2-ridge midstripe and white-hyaline margins, abruptly contracted to a hair-like deciduous tip 0.5-1 mm; strobili small, to 1 cm, subsessile, apiculate.
Notes
Strobili produced May and June
Wetland indicator: FAC
Our plants are var. variegatum. The hybrid with E. hyemale is E. xmackaii (Newman) Brichnan, pictured below, is intermediate in size with sheath teeth with less prominent white margins.
References
Gleason, Henry A.
and A. Cronquist. 1991. Manual of Vascular Plants of Northeastern United States
and Adjacent Canada. Second Ed.
The New York Botanical Garden. Bronx, NY
Michael Hough © 2018 |