Equisetum x mackaii (Newman) Brichan
Family: Equisetaceae
MacKay's horsetail
Equisetum x mackaii image
Michael A. Rosenthal  
Etymology: Equisetum: Latin for "horsetail" from equus, "horse," and seta, "bristle"
Plants: perennial fern ally
Habitat: shores and sands
Conservation Status: Native