Equisetum pratense

Aerial stems dimorphic; vegetative stems green, branched, 16–50 cm; hollow center 1/6–1/3 stem diam. Sheaths somewhat elongate, 3–5 × 2–4 mm; teeth 8–18, narrow, 1.5–4 mm, centers dark and margins white. Branches in regular whorls, horizontal to drooping, solid; ridges 3; valleys channeled; 1st internode of each branch equal to or longer than subtending stem sheath; sheath teeth deltate. Fertile stems brown, with stomates, initially unbranched, persisting and becoming branched and green after spore discharge.

Phenology: Cones maturing in late spring.
Habitat: Meadows, wet woodlands
Elevation: 0–2000 m

Alta., B.C., Man., N.B., Nfld., N.W.T., N.S., Ont., P.E.I., Que., Sask., Yukon, Alaska, Conn., Ill., Iowa, Maine, Mass., Mich., Minn., N.H., N.Y., N.Dak., Vt., Wis., n Eurasia to ne China, Japan in Hokkaido.

Discussion

Selected References

None.

Lower Taxa