Sporobolus cynosuroides (L.) P. M. Peterson & Saarela

Spartina cynosuroides (L.) Roth, Catalecta Bot. 3: 10. 1806
Dactylis cynosuroides L. Sp. PI. 71. 1753. (Localities cited, Virginia and Canada.)
Trachynotia polystachya Michx. Fl. Bor. Am. 1: 64. 1803. (Type from South Carolina, Michaux.)
Trachynotia cynosuroides Michx. Fl. Bor. Am. 1: 64. 1803. (Based on Dactylis cynosuroides L.
but misapplied to S. pectinata.) Paspalum cynosuroides Brot. Fl. Lusit. 1: 83. 1804. (Based on Dactylis cynosuroides L.) Limnelis cynosuroides Rich.; Pers. Syn. PI. 1: 72. 1805. (Based on Dactylis cynosuroides L.) Limnetis polystachia Rich.; Pers. Syn. PI. 1: 72. 1805. (Based on Trachynotia polystachya Michx.) Spartina polystachya Beauv. Agrost. 25, 178, 179. 1812. (Presumably based on Trachynotia
polystachya Michx.) Cynodon cynosuroides Rasp. Ann. Sci. Nat. 5: 303. 1825. (Based on Spartina cynosuroides Roth.) Spartina cynosuroides var. polystachya Beal, Grasses N. Am. 2: 398. 1896. (Based on Trachynotia
polystachya Michx.)
Culms as much as 3 meters tall, stout, erect from coarse, widely spreading rhizomes; sheaths much longer than the intemodes, rounded, the collar more or less pubescent; ligule ciliate, 1-3 mm. long; blades elongate, attenuate, flat, 1-2.5 cm. wide at the somewhat rounded base, glabrous on both surfaces, the margins scabrous; panicle 15-35 cm. long; spikes numerous, narrowly ascending to somewhat spreading, crowded, the lower mostly 8-15 cm. long, the peduncles as much as 4 cm. long, the rachis scabrous on the margins; spikelets crowded; glumes conspicuously hispid on the keels, scabrous on the margins, the first acute, half as long as the lemma, the second acuminate, awnless, much longer than the lemma; lemma about 8 mm. long, scabrous at least on the upper half, hispid on the keel, the tip with two shallow rounded lobes; palea exceeding the lemma, narrowed toward the summit, more or less scabrous.
Typb locality: Virginia.
Distkibution: Brackish marshes along the coast, Mu.ssachusetts to Florida and Texas; Bahama Islands.

Perennials, Aquatic, leaves emergent, Terrestrial, not aquatic, Rhizomes present, Rhizome elongate, creeping, stems distant, Stolons or runners present, Stems nodes swollen or brittle, Stems erect or ascending, Stems solitary, Stems caespitose, tufted, or clustered, Stems swollen at base, tuberous, cormous or bulbous, Stems terete, round in cross section, or polygonal, Stem internodes solid or spongy, Stem internodes hollow, Stems with inflorescence less than 1 m tall, Stems with inflorescence 1-2 m tall, Stems with inflorescence 2-6 m tall, Stems, culms, or scapes exceeding basal leaves, Leaves mostly cauline, Leaves conspicuously 2-ranked, distichous, Leaves sheathing at base, Leaf sheath mostly open, or loose, Leaf sheath smooth, glabrous, Leaf sheath hairy at summit, throat, or collar, Leaf sheath and blade differentiated, Leaf blades linear, Leaf blades 2-10 mm wide, Leaf blades 1-2 cm wide, Leaf blades mostly flat, Leaf blade margins folded, involute, or conduplicate, Leaf blades mostly glabrous, Leaf blades scabrous, roughened, or wrinkled, Ligule present, Ligule a fringe of hairs, Inflorescence terminal, Inflorescence solitary, with 1 spike, fascicle, glomerule, head, or cluster per stem or culm, Inflorescence a panicle with narrowly racemose or spicate branches, Inflorescence branches more than 10 to numerous, Inflorescence branches 1-sided, Rachis angular, Flowers bisexual, Spikelets pedicellate, Spikelets sessile or subsessile, Spikelets laterally compressed, Spikelet less than 3 mm wide, Spikelets with 1 fertile floret, Spikelets solitary at rachis nodes, Spikelets all alike and fertille, Spikelets bisexual, Spikelets disarticulating below the glumes, Spikelets secund, in rows on one side of rachis, Rachilla or pedicel glabrous, Glumes present, empty bracts, Glumes 2 clearly present, Glumes distinctly unequal, Glumes equal to or longer than adjacent lemma, Glume equal to or longer than spikelet, Glumes keeled or winged, Glume surface hairy, villous or pilose, Glumes 1 nerved, Glumes 3 nerved, Lemmas thin, chartaceous, hyaline, cartilaginous, or membranous, Lemma 3 nerved, Lemma glabrous, Lemma body or surface hairy, Lemma apex truncate, rounded, or obtuse, Lemma awnless, Lemma margins thin, lying flat, Lemma straight, Palea present, well developed, Palea membranous, hyaline, Palea longer than lemma, Palea 2 nerved or 2 keeled, Stamens 3, Styles 2-fid, deeply 2-branched, Stigmas 2, Fruit - caryopsis.

Sporobolus cynosuroides is a species of grass known by the common names big cordgrass and salt reedgrass. It is native to the East Coast and Gulf Coast of the United States, where it grows in coastal habitat such as marshes, lagoons, and bays.

This species is a rhizomatous perennial grass which can grow up to 10 feet tall. The leaves are up to 24 inches long and up to an inch wide. The ligule is hairy. The stem can be ¾ of an inch in diameter at the base. The inflorescence contains up to 40 spikes each up to 3 inches long.

This grass grows in flooded saline soils such as those in salt marshes. It is associated with marsh-hay cordgrass (Spartina patens) and common reed (Phragmites australis).

brackish marshes