Pacific Island Ecosystems at Risk (PIER)

  [   PIER species lists  ]   [   PIER home  ]

Arrhenatherum elatius
(L.) Mert. & Koch, Poaceae
Click on an image for links to BIGGER PICTURES


Present on Pacific Islands?  yes

Primarily a threat at high elevations?  no

Other Latin names:  Arrhenatherum avenaceum (Scop.) P. Beauv.; Avena bulbosa Willd.; Avena elatior L.

Common name(s): [more details]

Chinese: yan mai cao

English: bulbous oatgrass, false oatgrass, French ryegrass, French-rye, meadow oat grass, onion couch, onion twitch, onion-root twitch, tall oatgrass, tuber oat grass

French: avoine élevée, fenasse, fromental, fromental élevé

Japanese: ō-kani-tsuri

Spanish: fromental, mazorilla, raygras Françés

Habit:  grass

Description:  "Loosely tufted, coarse perennials, (40)-60-150 cm. Leaf-sheath ± chartaceous, smooth, or rarely minutely scabrid, sometimes with scattered long fine hairs. Ligule 1-3-(4) mm, truncate to ± obtuse, erose, ± ciliate, abaxially minutely scabrid to minutely hairy. Leaf-blade 15-30-(50) cm x 2-12 mm, minutely scabrid on ribs, to ± smooth, adaxially often with scattered long fine hairs; margins minutely, closely scabrid, tip acute, scabrid. Culm erect or ± spreading, stout. Panicle (4)-14-32 cm, erect or nodding, dense or lax, slender and lanceolate or with lower branches spreading; rachis smooth below, scabrid above, branches and pedicels slender, scabrid. Spikelets 7.5-9.5-(11) mm, shining, green or purplish. Glumes acute, sometimes finely scabrid, nerves finely scabrid; lower (3.5)-4.5-6-(6.8) mm, lanceolate, 1-nerved, upper ≤ spikelet, ovate-lanceolate, 3-nerved. Lemma (7)-8-9 mm, 7-nerved, ovate-lanceolate, hyaline near acute tip, nerves distinct, finely scabrid, upper or both lemmas with scattered fine hairs in lower 1/2; awn of lower lemma 8-16.5 mm; awn of upper lemma 0.5-10 mm, or 0. Palea narrower than lemma, keels finely ciliate, interkeel minutely scabrid, apex shortly bifid. Callus usually ringed by short stiff hairs. Rachilla prolongation 1.5-2.5 mm, delicate, glabrous. Anthers 3.5-5 mm. Gynoecium: ovary 0.6-0.8 mm; stigma-styles 1.5-1.8 mm. Caryopsis 2.5-3.8 x 0.8-1.2 mm"  (Edgar & Connor, 2000; p. 300).

Description from GrassBase.

Habitat/ecology:  "Floodplains, riparian habitats, damp places.  This grass grows best in moist soils... Dead shoots are highly flammable and the grass resprouts quickly after burning.  The plant forms species poor clones that may cover hundreds of acres and displace native vegetation and exclude associated wildlife species"  (Weber, 2003; p. 57).

In New Zealand, "Along roadsides and railway lines, on clay banks, in waste ground, paddocks and sometimes on dune margins, or a garden weed; sea level to montane"  (Edgar & Connor, 2000; p. 300).

Propagation:  "Spreads mainly by stem and rhizome fragments.  In North America, no viable achenes are formed.  Even small rhizome fragments can regrow and form new plants; rhizome fragments are carried by rivers and streams"  (Weber, 2003; p. 57).

Native range:  Canary Islands, northern Africa, Europe, western Asia (GRIN).

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. 1482)
Voucher cited: Hosaka 1553 (BISH)
State of Hawaii
Hawaiian Islands
Maui Island introduced
invasive
Starr, Forest/Starr, Kim/Loope, Lloyd L. (2003) (p. 29)
East Maui. Voucher cited: Starr & Martz 010721-2 (BISH)
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)
New South Wales introduced
invasive
cultivated
Csurhes, S./Edwards, R. (1998) (pp. 142-143)
Australia
Australia (continental)
Queensland introduced
invasive
cultivated
Csurhes, S./Edwards, R. (1998) (pp. 142-143)
Canada (British Colombia)
Province of British Columbia
Canada (British Columbia) introduced
U.S. Dept. Agr., Agr. Res. Serv. (2013)
Chile (continental)
Chile
Chile (Republic of)   Hafliger, Ernst/Scholz, Hildemar (1980) (p. 21)
China
China
China (People's Republic of) introduced
cultivated
Zhengyi, Wu/Raven, Peter H./Deyuan, Hong (2013)
"Introduced to China as an ornamental garden plant and for forage".
Colombia
Colombia
Colombia (Republic of)   Holm, Leroy/Pancho, Juan V./Herberger, James P./Plucknett, Donald L. (1979) (pp. 32-33)
Japan
Japan
Japan (country) introduced
Mito, Toshikazu/Uesugi, Tetsuro (2004) (p. 192)
var. biaristatum Peterm, var. bulbosum Spenner, var. elatiusglabrescens Celakovsky, var. nodosum and var. subhirsutum Ascherson
New Zealand
New Zealand
New Zealand (country) introduced
invasive
Edgar, E./Connor, H. (2000) (p. 300)
United States (west coast)
United States (west coast states)
USA (Oregon) introduced
U.S. Dept. Agr., Agr. Res. Serv. (2013)
United States (west coast)
United States (west coast states)
USA (California) introduced
U.S. Dept. Agr., Agr. Res. Serv. (2013)
United States (west coast)
United States (west coast states)
USA (Washington) introduced
U.S. Dept. Agr., Agr. Res. Serv. (2013)
Indian Ocean
Country/Terr./St. &
Island group
Location Cited status &
Cited as invasive &
Cited as cultivated &
Cited as aboriginal introduction?
Reference &
Comments
La Réunion (France)
La Réunion Island
La Réunion Island introduced
invasive
U.S. Dept. Agr., Agr. Res. Serv. (2013)
Naturalized
Mauritius
Mautitius Islands (Mauritius and Rodrigues)
Mauritius Island introduced
invasive
U.S. Dept. Agr., Agr. Res. Serv. (2013)
Naturalized
Also reported from
Country/Terr./St. &
Island group
Location Cited status &
Cited as invasive &
Cited as cultivated &
Cited as aboriginal introduction?
Reference &
Comments
Canada (except British Colombia)
Canada
Canada (country) introduced
U.S. Dept. Agr., Agr. Res. Serv. (2013)
United States (continental except west coast)
United States (other states)
United States (other states) introduced
U.S. Dept. Agr., Agr. Res. Serv. (2013)

Control: 

Physical:  "Repeated cutting reduces vitality.  In the western USA, a late spring mowing with removal of cut material is recommended over a period of at least 3 years".

Chemical:  "Smaller patches can be sprayed with grass-selective or non-selective herbicides"  (Weber, 2003; p. 56).


Need more info? Have questions? Comments? Information to contribute? Contact PIER! (pier@hear.org)

  [   PIER species lists  ]   [   PIER home  ]

This page was created on 12 FEB 2007 and was last updated on 30 NOV 2008.