Alpestris translates as "growing in the mountains" from alpes, Alps + estris, from.
Rhizome: short-creeping, forming massive clumps.
Frond: 80 cm high by 20 cm wide, deciduous, monomorphic, blade/stipe ratio: 2:1 to 3:1.
Stipe: straw-colored or red-brown distally, (7--)10--30 cm, base dark red-brown to black with 2 rows of teeth, swollen, densely scaly at base, sparsely scaly upwards; scales broadly lanceolate to linear, to 1 cm long, pale brown or brown, vascular bundles: 2, lunate, uniting to a U-shape above.
Blade: 2-pinnate pinnatifid, narrowly oblong to ovate-oblong, slightly narrowed downwards, herbaceous, yellow-green to bright green, rachis , costae, and costules with small, pale brown scales.
Pinnae: 8 to 10 pair, lanceolate, 6--10 cm long, pointed at the apex, sessile; pinnules ovate-oblong, acute at apex, 1--2 cm long, 5--8 mm broad, deeply pinnatifid; costae grooved above, continuous from rachis to costae to costules; margins distinctly serrate, teeth sometimes folding over to protect the sori; veins free, forking, usually reaching the margins.
Sori: round to elliptic; in the drawing above it is reniform, medial between the costule and margin, indusium: missing or nearly so, though some forms have one early on, sporangia: black.
Habitat: wet talus slopes, rocky hillsides, alpine meadows.
Distribution: high elevations or high latitudes of the Northern Hemisphere.
Hardy to -30°C, USDA Zone 4, cool climate required.
generally looking like a smaller A. filix-femina with the distinguishing characteristics of the sorus shape, and the veins reaching the margin here, not in the lady fern.
Aspidium alpestre Hoppe
Pseudathyrium alpestre (Hoppe) Newman
Athyrium distentifolium Tausch ex Opiz
Athyrium alpestre subsp. americanum (Butters) Lellinger
Athyrium alpestre var. gaspense Fernald
Athyrium americanum (Butters) Maxon
Athyrium distentifolium Tausch ex Opiz subsp. americanum (Butters) Hultén
Athyrium distentifolium var. americanum (Butters) Cronquist