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..
Similar to S". mucronatum Michx., but often stiffer and more glaucous, with always smooth-edged stems and leaves, usually broader, more gibbous spathes, and pale blue or frequently white flowers. Stem 1/2"-1" wide, the leaves rather broader; spathes green to dull pink-purple, the bracts commonly scabrous-puberulent all over, but sometimes glabrous, the outer one usually less slenderly prolonged than in S". mucronatum, and not united-clasping at base, or but slightly so, 1/2'-2' long, rarely more than twice longer than the inner bract, which emerges more abruptly from the base of the spathe than in S". mucronatum, and has more broadly hyaline edges; capsules pale, trigonous-sub-globose, I"-2" high.
S. arenicola Bicknell, Bull. Torr. Club 26: 496. 1899.
Deep green or glaucescent, often purplish-tinged, the base of the tufts coarsely fibrous. Leaves stiff, attenuate, 1/2"-1 1/2" wide, closely striate, usually serrulate; stem erect, often curved, 8'-20' high, stiff, the firm wings striate, mostly serrulate; node commonly only one, its erect leaf conspicuous, attenuate-acute, the compressed broadened base strongly striate; peduncles 2-4, curved; spathes erect, the acute bracts firm and strongly striate, slightly unequal; flowers sometimes as many as 12, deep violet-blue, 4"-5" long; capsules dark and thick-walled on erect slightly exserted pedicels, broadly oval or obovoid, 2 '-3' high.
Sandy soil, Massachusetts to New Jersey and North Carolina, mostly near the coast. June-July.
Sisyrinchium Farwellii Bicknell, known only from southeastern Michigan, differs in not turning black in drying and has flexuous rather than straight pedicels and slightly smaller capsules.
515. 1890. Not Cav. S. graminoides Bicknell, Bull. Torr. Club 23: 133. 1896. S. gromineum Curtis, Bot. Mag. pi. 464. 1789. Not Lam.
Rather light green, somewhat glaucous; stem broadly 2-winged, stout, erect, or reclining, 8'-18' tall, usually terminating in two unequal branches subtended by a conspicuous grassy leaf. Basal leaves equalling or shorter than the stem, 1"-3," wide; often lax and grass-like; edges of stems and leaves usually perceptibly rough-serrulate; bracts 1' long or less, green, nearly or quite equal but the outer one occasionally prolonged; umbels 2-4-flowered; pedicels filiform, 8"-12" long, exceeding the bracts, finally often spreading or recurved; flowers 6"-9' broad; petals sparsely pubescent on outer surface; capsule subglobose, 2 1/2'-3" in diameter when mature; seeds black, globose, about 1/2"-2/3" in diameter, pitted.