Present on Pacific Islands?  yes

Primarily a threat at high elevations?  no

Other Latin names:  Anthistiria villosa Poir.; Themeda gigantea (Cav.) Hack. subsp. villosa (Poir.) Hack.

Common name(s): [more details]

Chinese: jian

English: greater tasselgrass, Lyon's grass, silky kangaroo grass

Habit:  grass

Description:  "Robust perennials; culms tufted, stout, 20-40 dm tall, solid; culm base compressed, flabellate.  Sheaths keeled, ± compressed, margins overlapping, glabrous; ligule membranous, ciliate; blades up to 150 cm long, up to 20 mm wide, glabrous, midrib white, prominent, margins and nerves scabrous on upper surface, apex acuminate, base narrowed, to the sheath.  Inflorescences large, compound, drooping, paniculate, spathes 3-3.5 cm long, subtending a flattened rachis, apex pubescent, racemes of spikelet pairs at about the middle of the spathe; involucral and pedicellate spikelets reddish brown, similar in shape, narrowly fusiform, acuminate, 15-20 mm long, pedicels rufous pubescent; sessile spikelet with a callus ca. 2 mm long, densely pubescent with rufous hairs, first glume ovate, 10-nerved, the nerves reticulate toward apex, densely rufous pubescent between the nerves, apex acute, first lemma 1-nerved, apex acute; second lemma 1-nerved, hyaline, prolonged into a twisted pubescent awn up to 42 mm long, second palea lanceolate, nerveless, hyaline.  Caryopsis reddish brown, fusiform, ca. 5 mm long"  (Wagner et al., 1999; pp. 1599, 1601).

Description from GrassBase.

Habitat/ecology:  In Hawai‘i, "naturalized in dry pastures, along roadsides, and other disturbed sites, 0-700 m"  (Wagner et al., 1999; p.1601); "forms tall pure stands in pastures and disturbed areas.  Awns irritating to humans and animals"  (Motooka et al., 2003).

Propagation:  Seed

Native range:  Southeastern Asia (Wagner et al., 1999; p.1601).

Presence:

Pacific
Country/Terr./St. & Island group	Location	Cited status & Cited as invasive & Cited as cultivated & Cited as aboriginal introduction?	Reference & Comments
State of Hawaii Hawaiian Islands	Hawai‘i (Big) Island	introduced invasive	Wagner, Warren L./Herbst, Derral R./Sohmer, S. H. (1999) (p. 1601)
State of Hawaii Hawaiian Islands	Kaua‘i Island	introduced invasive	Wagner, Warren L./Herbst, Derral R./Sohmer, S. H. (1999) (p. 1601)
State of Hawaii Hawaiian Islands	O‘ahu Island	introduced invasive	Wagner, Warren L./Herbst, Derral R./Sohmer, S. H. (1999) (p. 1601) Voucher cited: Lee & Weller 121 (BISH)
Philippines Philippine Islands	Philippine Islands		Hafliger, Ernst/Scholz, Hildemar (1980) (p. 139)

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)	Australia (continental)		Hafliger, Ernst/Scholz, Hildemar (1980) (p. 139)
China China	China (People's Republic of)	native	U.S. Dept. Agr., Agr. Res. Serv. (2011)
China China	Hong Kong	native	Wu, Te-lin (2001) (p. 349) In thickets and grassland on hillslopes.
Indonesia Indonesia	Indonesia (Republic of)	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. 86) Common
Thailand Thailand	Thailand (Kingdom of)	native	U.S. Dept. Agr., Agr. Res. Serv. (2011)
Vietnam Vietnam	Vietnam (Socialist Republic of)		Holm, Leroy/Pancho, Juan V./Herberger, James P./Plucknett, Donald L. (1979) (p. 361)

Comments:  A declared noxious weed in Hawai‘i (GRIN).

Control: 

Physical:  "Intensive grazing of succulent regrowth also effective"  (Motooka et al., 2003).

Chemical: "Sensitive to foliar application of glyphosate; application more effective if the grass is mowed and the regrowth treated"  (Motooka et al., 2003).

Additional information:
Excerpt from the book "Weeds of Hawaii‘s Pastures and Natural Areas; An Identification and Management Guide" (Motooka et al., 2003). (PDF format).

Additional online information about Themeda villosa is available from the Hawaiian Ecosystems at Risk project (HEAR).

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

Taxonomic information about Themeda villosa 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.

Hafliger, Ernst/Scholz, Hildemar. 1980. Grass weeds, vol. 1. CIBA-GEIGY Ltd., Basle, Switzerland. 142 pp. + plates.

Holm, Leroy/Pancho, Juan V./Herberger, James P./Plucknett, Donald L. 1979. A geographical atlas of world weeds. John Wiley & Sons, New York. 391 pp.

Motooka, Philip/Castro, Luisa/Nelson, Duane/Nagai, Guy/Ching, Lincoln. 2003. Weeds of Hawaii‘s Pastures and Natural Areas; An Identification and Management Guide. College of Tropical Agriculture and Human Resources, University of Hawaii at Manoa. 184 pp.

U. S. Government. 2011. Integrated Taxonomic Information System (ITIS) (on-line resource).

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

Wagner, Warren L./Herbst, Derral R./Sohmer, S. H. 1999. Manual of the flowering plants of Hawaii. Revised edition. Bernice P. Bishop Museum special publication. University of Hawai‘i Press/Bishop Museum Press, Honolulu. 1919 pp. (two volumes).

Wu, Te-lin. 2001. Check List of Hong Kong Plants. Hong Kong Herbarium and the South China Institute of Botany. Agriculture, Fisheries and Conservation Department Bulletin 1 (revised). 384 pp.

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