Equisetum hyemale

Equisetum hyemale (rough horsetail) is an evergreen perennial herbaceous pteridophyte in the horsetail family Equisetaceae native to Eurasia and Greenland. It was formerly widely treated in a broader sense including a subspecies (subsp. affine) in North America, but this is now treated as a separate species, Equisetum praealtum.