Cystopteris tenuis (Michx.) Desv.
Mackay's fragile fern, Mackay's brittle fern, upland brittle bladder fern
Mackay's fragile fern, Mackay's brittle fern, upland brittle bladder fern
July 9,
Arnold Arboretum, Jamaica Plain, Boston
Identification tentative. A small fern growing close to a large cinnamon fern at the bottom of a fairly steep slope facing Unquity Road (facing east)