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..
Light green, rootstocks extensively creeping, culms normally dioecious, slender, erect, smooth or nearly so, 4'-12' tall. Leaves 3/4"- 1 1/4" wide, somewhat involute in drying, shorter or longer than the culm, tapering to a long tip; spikes linear or oblong, elliptic, 2 1/2"-8" long, several or numerous in a dense terminal oblong or ovoid head 1-2' long; perigynia ovate-lanceolate, about 2" long, less than 1" wide, faintly several-nerved, on both sides, rounded at base, the rough, at length bidentate, tapering beak about one-half as long as the body; scales pale greenish brown, or straw-colored, lanceolate, scarious, smooth-awned, much longer than the perigynia and completely concealing them; stigmas 2.
In dry soil, Manitoba to Nebraska and New Mexico, west to British Columbia and California. June-Aug.
Carex Sartwellii Dewey, Am. Journ. Sci. 43: 90. 1842.
Culms slender, stiff, erect, rough above, 3-angled, 1°_3° tall, from elongated dark rootstocks. Leaves 1"-2" wide, mostly shorter than the culm, long-attenuate at the tip; bracts setaceous, usually very small, or 1 or 2 of the lower sometimes elongated; spikes numerous, ovoid or oblong, usually staminate or androgynous, 2" - 4" long, usually densely aggregated in a narrow but heavy head l'-2' long and 5" wide, or the lower somewhat separated; perigynia elliptic-lanceolate or ovate-lanceolate, 1 1/4"-2" long and 3/4-1" wide, thin-margined, ascending, nerved on both faces, tapering into a short 2-toothed beak; scales ovate, obtuse or subacute, pale brown, scarious-margined, about equalling the perigynia; stigmas 2.
In swamps, Ontario to British Columbia, south to central New York, Illinois, Arkansas and Utah. May-July.
Carex arenaria L. Sp. PI. 973. 1753.
Rootstock extensively creeping, culms erect, slender, slightly scabrous above, 4-15' high. Leaves 3/4"-1 1/4" wide, very long-pointed, shorter than the culm; lower bract subulate, sometimes 1 1/2' long; spikes oblong, 3"-6" long, aggregated into a terminal ovoid head I'-2' long, the terminal commonly staminate, the middle ones staminate at the top, the lower usually wholly pistillate; perigynia lanceolate, 2"-2$" long, wing-margined above, strongly several-nerved on both sides, the flat strongly 2-toothed serrulate beak nearly as long as the body and decurrent on its summit; scales lanceolate, light brown, long-acuminate or awned, about equalling the perigynia; stigmas 2.
On sea beaches near Norfolk, Virginia. Adventive or naturalized from Europe. Stare. Sea-sedge. Sea-bent. June-July.