Present on Pacific Islands?  no

Primarily a threat at high elevations?  no

Other Latin names:  Schoenoplectus grossus (L. f.) Palla; Scirpus grossus L. f.

Common name(s): [more details]

Chinese: da biao cao

Habit:  sedge

Description:  "Perennial; stolons slender, about 5 mm thick.  Culms 1 to few to a tuft, 1-2 m tall, 2-2.5 cm thick at base, 0.7-1 cm thick below the inflorescence, sharply 3-angled, spongy, faces concave, septate-nodose, smooth, with a corm-like hard enlargement at base.  Leaves few to a culm, linear, 1.5-3 cm wide, mostly equaling the culm, 1-ribbed, flattish-plicate, somewhat thickish, soft, septate-nodose, gradually attenuate upward, sheaths spongy, prominently septate-nodose, tightly surrounding culm base.  Inflorescence a large terminal corymb with primary, secondary and tertiary rays; rather dense, 6-15 cm long and as broad; bracts 3-4, leaf-like, exceeding the inflorescence, the longest up to 50 cm long; rays many, somewhat compressed, scabrous on edges as in secondary rays; bractlets spathaceous-scale-like, about 8 mm long, brownish-stramineous; secondary rays slender, 1.5-4 cm long.  Spikelets solitary, pedicellate and in the terminal one sessile, ellipsoid to long-ellipsoid, 6-10 mm long, 3.5-4 mm across, densely many-flowered, rounded at apex, light brownish-rust-coloured.  Scales elliptical to oval-elliptical, brownish-rust-coloured, boat-shaped, keel green, apex obtuse, nerveless and brown-striolate on the both sides, ciliolate on the upper margin and upward.  Achenes broadly obovate nearly obdeltoid, 1-1.5 mm long, 1 mm wide or less, subcompressed-triangular, apiculate at apex, cuneate at base, faces flattish, stramineous-brown; hypogynous bristles 6 (sometimes 5), light brown, slightly exceeding achene, the longer 2 mm long or more, subcomressed, retrorsely scabrous with loose aculeae except at base; style about 3 mm long, the upper half trifid (stigmas), brownish-papulose.  Stamens 3, anther linear, 1.5 mm long, connective deltoid, reddish-brownish, very short" (Dassanayake, 1983; pp. 154-155).

Habitat/ecology:  In Sri Lanka, "marshy places both inland and near the coast; often forming a large community" (Dassanayake, 1983; pp. 154-155).

Propagation:  Seed

Native range:  India to southeast Asia, China, Japan, Malesia, northern Australia (GRIN).

Presence:

Pacific
Country/Terr./St. & Island group	Location	Cited status & Cited as invasive & Cited as cultivated & Cited as aboriginal introduction?	Reference & Comments
Japan (offshore islands) Bonin (Ogasawara) Islands	Bonin (Ogasawara) Islands	introduced	Kato, Hidetoshi (2007) As Schoenoplectus grossus (L.f.) Palla
Philippines Philippine Islands	Philippine Islands	native	U.S. Dept. Agr., Agr. Res. Serv. (2011)
Philippines Philippine Islands	Philippine Islands	native	Merrill, Elmer D. (1925) (p. 117) In fresh-water swamps at low altitudes.

Pacific Rim
Country/Terr./St. & Island group	Location	Cited status & Cited as invasive & Cited as cultivated & Cited as aboriginal introduction?	Reference & Comments
Australia Australia (continental)	Northern Territory	native	U.S. Dept. Agr., Agr. Res. Serv. (2011)
Australia Australia (continental)	Queensland	native	U.S. Dept. Agr., Agr. Res. Serv. (2011)
Cambodia Cambodia	Cambodia (Kingdom of)	native	U.S. Dept. Agr., Agr. Res. Serv. (2011)
China China	China (People's Republic of)	native	U.S. Dept. Agr., Agr. Res. Serv. (2011)
Indonesia Indonesia	Indonesia (Republic of)	native	U.S. Dept. Agr., Agr. Res. Serv. (2011)
Japan Japan	Japan (country)	native	U.S. Dept. Agr., Agr. Res. Serv. (2011)
Malaysia Malaysia	Malaysia (country of)	native	U.S. Dept. Agr., Agr. Res. Serv. (2011)
Singapore Singapore	Singapore (Republic of)	native	Chong, Kwek Yan/Tan, Hugh T. W./Corlett, Richard T. (2009) (p. 10) Common
Thailand Thailand	Thailand (Kingdom of)	native	U.S. Dept. Agr., Agr. Res. Serv. (2011)
Vietnam Vietnam	Vietnam (Socialist Republic of)	native	U.S. Dept. Agr., Agr. Res. Serv. (2011)

Additional information:
Additional online information about Actinoscirpus grossus is available from the Hawaiian Ecosystems at Risk project (HEAR).

Information about Actinoscirpus grossus as a weed (worldwide references) may be available from the Global Compendium of Weeds (GCW).

Taxonomic information about Actinoscirpus grossus may be available from the Germplasm Resources Information Network (GRIN).

References:

Chong, Kwek Yan/Tan, Hugh T. W./Corlett, Richard T. 2009. A checklist of the total vascular plant flora of Singapore: native, naturalised and cultivated species. Raffles Museum of Biodiversity Research, National University of Singapore. 273 pp.

Dassanayake, M. D., gen. ed. 1983. A revised handbook to the flora of Ceylon. Vol V. Amerind Pub. Co., New Delhi. 476 pp.

Kato, Hidetoshi. 2007. Herbarium records of Makino Herbarium, Tokyo Metropolitan University. Personal communication.

Merrill, Elmer D. 1925. An enumeration of Philippine flowering plants, vol. 1 [reprint]. Bureau of Printing, Manila. 463 pp.

U.S. Dept. Agr., Agr. Res. Serv. 2011. National Genetic Resources Program. Germplasm Resources Information Network (GRIN). Online searchable database.

Zhengyi, Wu/Raven, Peter H./Deyuan, Hong. 2011. Flora of China (online resource).