Pacific Island Ecosystems at Risk (PIER)

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Themeda villosa
(Poir) A.Camus, Poaceae
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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. (2013)
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. (2013)
Malaysia
Malaysia
Malaysia (country of) native
U.S. Dept. Agr., Agr. Res. Serv. (2013)
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. (2013)
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).


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This page was created on 7 FEB 2007 and was last updated on 10 MAY 2017.