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 vulpina Carey, in A. Gray, Man. 541. 1848. Not L. I/53. Carex conjuncta Boott, 111. 3: 122. 1862.
Light green, culms roughish above, sharply 3-angled but flattened, somewhat winged, soft, erect, 1 1/2°-3° tall. Leaves shorter than or sometimes equalling the culm, soft, flat, rough-margined, 2 1/2"-5" wide; bracts small and bristle-like or wanting; spikes androgynous, 10 or fewer, in a terminal elongated head I-3' long, approximate, or the lower separated; perigynia ovate-lanceolate, rounded and slightly spongy at base, green even in age, 1 1/2"-2" long, thickened at the base, strongly several-nerved on outer face, tapering into a roughish 2-toothed beak shorter than the body; scales ovate to ovate-triangular, cuspidate or short-awned, about as long as the perigynia; stigmas 2.
Carex vulpinoidea Michx. Fl. Bor. Am. 2: 169. 1803.
Culms slender, stiff, sharply 3-angled, very rough above, 1°-3° tall. Leaves I"- 2 1/2" wide, elongated, many exceeding the culm; sheaths tight, transversely rugulose; bracts bristle-like, sometimes 2'-3' long; spikes ovoid-oblong, androgynous, densely flowered, 2"-.4" long, very numerous in a compact or somewhat interrupted narrow head, 1 1/2' -5' (usually 2'-3') long, the lower ones distinguishable, sometimes compound, the upper confluent; perigynia narrowly to very broadly ovate, 1"-1 1/4" long, rather more than \" wide, greenish yellow, flat, plano-convex, several-nerved on the outer face, nerveless or 1-3-nerved on the inner, ascending or spreading at maturity, tipped with a lanceolate 2-toothed beak about as long as the body; scales lanceolate, usually strongly awned, about as long as the upper and longer than lower perigynia, but narrower; stigmas 2.
In swamps and wet meadows. New Brunswick to Manitoba, south to Florida, Louisiana, Nebraska and Texas. Ascends to 2500 ft. in Virginia. June-Aug.
Carex xanthocarpa var. annectens Bicknell. Bull. Torr. Club 23: 22. 1896.
Carex annectens Bicknell, Bull. Torr. Club 35: 492. 1908.
Culms stoutish, rough above, 1°-5° tall, exceeding the leaves. Leaves 1"-3 1/2" wide; head oblong or ovoid, usually dense, \'-2\' long; sheaths tight, transversely rugulose; spikes androgynous, numerous, ovoid, many-flowered, short; bracts much less conspicuous than in the last; perigynia bright yellow, plano-convex, ovate to suborbicular, 1 1/2" long, with a narrowed or truncate base, and abruptly narrowed into a short minutely 2-toothed beak, nerveless, or obscurely few-nerved on the outer face; scales acuminate, short-awned.
In fields, Maine to New York, Iowa, Maryland and Mis-souri. lune-Aug.