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..
Carex digitalis Willd. Sp. PI. 4: 298. 1805.
Glabrous, bright green, not at all glaucous, culms weak, slender, smooth, usually reclining, 4'-18' long. Leaves flat, 1"-2 1/2" wide, usually longer than the culm; bracts similar, the second exceeding the culm; staminate spike stalked; pistillate spikes 2-4, linear, loosely alternately 3-12-flowered, 5-15" long, the upper nearly sessile, the others filiform-stalked and widely spreading or drooping; perigynia ovoid-oblong, sharply triangular, many-nerved, brown when ripe, narrowed at both ends, scarcely 1 1/2" long, more than i" thick, the very short beak slightly oblique; scales lanceolate or ovate-lanceolate, scarious-margined, acute, acuminate or short-awned, shorter than or the lower about equalling the perigynia; stigmas 3.
Carex laxiculmis Schwein. Ann. Lye. N. Y. 1: 70. 1824.
Carex retrocurva Dewey, Wood's Bot. 423. 1845.
Glabrous, varying from strongly glaucous to deep green, culms filiform, smooth or very nearly so, ascending or diffuse, 6'-2° long. Sterile culm-leaves elongated, 2"-6" wide, those of fertile culms shorter than the culms; bracts similar, usually short; staminate spike long-stalked; pistillate spikes 2-4, oblong, rather loosely 5-10-flowered, 3"-6" long, about 2" thick, drooping on long hair-like stalks or the upper short-stalked and erect; perigynia broadly ovoid-oblong, sharply 3-angled, many-nerved, 11/2"-2" long and rather more than 1/2" thick, narrowed at both ends, but scarcely beaked, longer than the ovate, green, cuspidate or short-awned scales; stigmas 3.
In woods and thickets, Maine to southern Ontario, Michigan, Virginia and Missouri. Ascends to 5600 ft. in Virginia. May-June.
Carex laxiflora var. latifolia Boott, 111. 38. 1858. Not C.
latifolia Moench, 1794. Carex albursina Sheldon, Bull. Torr. Club 20: 284. 1893.
Glabrous, rather deep green, culms nearly smooth, strongly flattened and winged, erect or spreading, 8-2° high. Basal leaves shorter than the culm, 3 1/2"-1 1/2' wide; bracts similar to the narrower culm-leaves, the upper strongly overtopping the spikes, sheaths loose; staminate spike sessile or nearly so, the scales obtuse; pistillate spikes 2-4, distant and narrowly linear, stalked or the upper sessile and close together, 1/2-1 1/4' long, loosely flowered; perigynia obovoid, obtusely 3-angled. many-nerved, 1/2"-2" long. 1" thick, tipped with a very short bent entire beak; scales broadly oblong, widely scarious-margined, very truncate or the lower rarely short-awned, shorter than the perigynia; stigmas 3.