This section is from the book "An Illustrated Flora Of The Northern United States, Canada And The British Possessions Vol1", by Nathaniel Lord Britton, Addison Brown. Also available from Amazon: An Illustrated Flora of the Northern United States, Canada and the British Possessions. 3 Volume Set..
P. scopulinum Maxon, Fern Bull. 8: 29. 1900.
Rootstock stout, ascending, with numerous cordlike roots. Leaves 9'-17' long, the stipe 2'-5' long, densely chaffy at the base with both broad and narrow bright brown scales; blades 6'-12' long, linear to narrowly oblong-lanceolate, 1 1/2'-2\' broad, coriaceous, the chaff largely deciduous from the rachis; pinnae numerous, 7" - 15" long, 4"-8" broad at the base, ovate, obtuse, the basal portion pinnately lobed, the apical half serrate with pointed or aculeate teeth, the lower pinnae usually much reduced; sori near the midvein; indusium large, somewhat lobed, glabrous.
On rocky slopes, Washington to Idaho, Utah and Southern California. Gaspe county, Quebec.
Aspidium Braunii Spenner, Fl. Frib. 1: 9. 1825. A. aculeatum var. Braunii Doell, Rhein. Fl. 21. 1843. Polystichum Braunii Fee, Gen. Fil. 278. 1850-52. Dryopteris aculeata var. Braunii Underw. Native Ferns, ed. 4, 112. 1893. Dryopteris Braunii (Spenner) Underw. in Br. & Brown, 111. Fl. ed. 1, 1: 15. 1896.
Rootstock stout, suberect. Stipes 4 -5 long, chaffy with both broad and narrow brown scales; blades lanceolate, 1°-2° long, herbaceous, 2-pinnate, the rachis chaffy; pinnae numerous, close, oblong-lanceolate, slightly broadest at the base, the middle ones 2 1/2'-4' long, the lower gradually shorter; pinnules ovate to oblong, truncate and nearly rectangular at the base, mostly acute, sharply toothed, beset with long soft hair-like scales; sori small, mostly nearer the midvein than the margin; indusium small, entire.
In rocky woods, Nova Scotia to Alaska, to northern New England, the mountains of Pennsylvania, to Michigan and British Columbia. Ascends to 5000 ft. in Vermont. Aug.