Panicum decompositum R.Br., Poaceae

Click on an image for links to BIGGER PICTURES

Present on Pacific Islands?  yes

Primarily a threat at high elevations?  no

Common name(s): [more details]

Chinese: duo zi shu

English: Australian millet, umbrella grass

Habit:  grass

Description:  "Perennial, densely tufted, mostly up to 90 cm tall, sometimes taller, usually pale glaucous-green; culms mostly simple, nodes glabrous to densely hairy.  Leaf sheaths glabrous or with few tubercular-based hairs; ligules membranous, ciliate, ca 2 mm long; leaf blades linear, apex acute or acuminate, margin flat or sometimes more or less inrolled when dry, up to 50 cm x 0.3-1 cm, glabrous or sprinkled with long tubercular-based hairs.  Panicles up to ca 35 cm long, lower branches rigid and straight, becoming flattened and broad towards their bases, up to ca 17 cm long, pedicels 1-4 mm long; spikelets 2.5-3.5 mm long; lower glume ca "-1/3 length of spikelet, nerves 1 or absent, upper glume ca as long as spikelet, 7-nerved; lower floret sterile, lemma ca as long as upper glume, 7-nerved, palea 2/3-7/8 as long as lemma; upper floret bisexual, lemma with beak-like apex, ca 2 mm long, palea ca as long as lemma"  (Stanley and Ross, 1989; vol. 3, pp. 197-199).

Description from GrassBase.

Habitat/ecology:  (no habitat/ecology info known by PIER)

Propagation:  Seed

Native range:  Australia (Stanley and Ross, 1989; vol. 3, pp. 197-199).

Presence:

Pacific
Country/Terr./St. & Island group	Location	Cited status & Cited as invasive & Cited as cultivated & Cited as aboriginal introduction?	Reference & Comments
New Caledonia New Caledonia	New Caledonia Islands		Swarbrick, John T. (1997) (p. 95)
Tonga Tongatapu Group	‘Eua Island		Whistler, W. A. (1988) (p. 54)
Tonga Tongatapu Group	‘Eua Island	introduced invasive	Yuncker, T. G. (1959) (p. 60) Voucher cited: Yuncker 15456

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	Stanley, T. D./Ross, E. M. (1989)
Australia Australia (continental)	Queensland	native	Stanley, T. D./Ross, E. M. (1989)
Taiwan Taiwan	Taiwan Island	introduced	Zhengyi, Wu/Raven, Peter H./Deyuan, Hong (2011)

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

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

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

References:

Stanley, T. D./Ross, E. M. 1989. Flora of south-eastern Queensland. Queensland Department of Primary Industries, Misc. Pub. 81020. 3 Volumes.

Swarbrick, John T. 1997. Weeds of the Pacific Islands. Technical paper no. 209. South Pacific Commission, Noumea, New Caledonia. 124 pp.

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

Whistler, W. A. 1988. Checklist of the weed flora of western Polynesia. Technical Paper No. 194, South Pacific Commission, Noumea, New Caledonia. 69 pp.

Yuncker, T. G. 1959. Plants of Tonga. Bishop Museum Bull. 220. Bishop Museum Press, Honolulu. 343 pp.

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