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 Careyana Torr.; Dewey, Am. Journ. Sci. 30: 60. /. 88. 1836.
Glabrous, bright green, culms slender, erect or .somewhat reclining, smooth or nearly so, 1°-2 1/2° tall. Basal leaves flat, 3"-6" wide, much shorter than the culm; bracts narrow, short, with very long purplish-tinged sheaths; staminate spike usually long-stalked, large; pistillate spikes 1-3, erect, loosely 3-8-flow-ered, less than 1' long, the upper short-stalked and approximate, the lower long-stalked and remote; perigynia ovoid-elliptic, very sharply 3-angled, many-nerved, 2 3/4" long or more and over 1" thick, the short beak slightly oblique, entire; scales ovate with hyaline margins, cuspidate or awned, about half length of perigynia; stigmas 3.
Carex platyphylla Carey, Am. Journ. Sci. (II.) 4: 23. 1847.
Glabrous, pale green and glaucous, culms slender, spreading or reclining, 4'-15' long. Leaves of sterile culms flat and broad, 4 1/2"-12" wide, shorter than the culm, very smooth (except edges); those of fertile culms much reduced; bracts with long clasping sheaths, usually less than 2' long; staminate spike stalked; pistillate spikes 2-4, distant, erect, all slender-stalked or the upper one nearly sessile, loosely 4-10-flowered, 5"-10" long; perigynia ovoid-elliptic, 3-angled, many-nerved, slightly bent or nearly straight at the narrowed or short-beaked apex, 1 1/4"-ii" long, rather more than 1/2" thick, somewhat longer than the broadly ovate, acute, cuspidate or short-awned scales; stigmas 3.
In woods and thickets, Quebec and Ontario to Michigan, south to Virginia and Illinois. Ascends to 2500 ft. in Virginia. May-June.
Glabrous, pale green and glaucous, culms erect, very slender, smooth, only 2'-8' tall. Leaves flat, the larger 2"-4 1/2" wide, much longer than the culm; bract of second pistillate spike usually overtopping the culm; staminate spike small, 2"-4 1/2' long, sessile or nearly so; pistillate spikes 2 or 3, approximate, sessile or short-peduncled, or the lower one slender-stalked and nearly basal, all erect, loosely 5-10-flow-ered, 4"-8" long; perigynia oblong-ovoid, pale, sharply 3-angled, finely many-nerved, about 1 1/3" long, rather more than 1/2" thick, pointed at both ends; minutely straight-beaked or slightly bent, the orifice entire; scales ovate, thin, obtuse to short-cuspidate, about one-half as long as the perigynia; stigmas 3.
In moist woods and thickets, Massachusetts and New Jersey to Florida and Louisiana. Local. June-July.