Pacific Island Ecosystems at Risk (PIER)

  [   PIER species lists  ]   [   PIER home  ]

Najas marina
L., Hydrocharitaceae
Click on an image for links to BIGGER PICTURES


Present on Pacific Islands?  no

Primarily a threat at high elevations?  no

Common name(s): [more details]

Chinese: da ci zao

English: bushy pondweed, holly-leaf naiad, holly-leaf waternymph, holly-leaved waternymph, marine naiad, prickly naiad, prickly waternymph, spiny-leaf naiad, spiny naiad, spiny waternymph, water nymph

French: naide marine

Japanese: ibaramo

Habit:  aquatic herb

Description:  "An herbaceous, dioecious, bright to pale green, submerged, rooted, quite variable aquatic plant growing to 80 cm, may be extremely brittle, adventitious roots from base and lower nodes; stems stout, dichotomously branched, spreading or ascending, may be glabrous sparsely toothed; leaves flat, almost always fleshy and sometimes triangular in cross-section, 0.5 to 4.5 cm long, 1.5 to 3.5 cm wide, tip acute to blunt, serrate with 5 to 10, rarely 40 marginal spines or teeth each side; spines may be greater than, equal to, or less than leaf width; dorsal leaf surface mostly with 1 to several spines; sheath with or without 1 to 5, rarely 10, mostly inconspicuous spines; auricles absent, or about 0.02 mm long if present; flowers solitary; staminate flower enclosed in spathe, spathe apex with or without a few minute spines, anthers 4-celled, 2.5 to 3.5 mm wide; pistillate flowers, 2 to 4 stigmas, 0.9 to 2 mm, spathe absent; fruit 1-seeded, plump, often reddish, finely reticulate, slightly asymmetrical, may have scurphy surface; seed elliptic to ovate, narrowing toward the tip, somewhat compressed, about 4 mm long and 2.5 mm wide, with rather irregularly arranged isodiametrical shiny testa patterns"  (Holm et al., 1997; p. 497).

Description from Flora of North America

Habitat/ecology:  Forms dense mats that choke out other species.  "The weed inhabits saline, alkaline and fresh waters of ponds, lakes, reservoirs, and slow-moving streams and canals.  Few species of aquatic weeds are aggressive in colonizing brackish waters (between fresh and salt water) but N. marina is conspicuous in doing so" (Holm et al., 1997; p. 497).

Propagation:  Seeds and rooting of fragments (Holm et al., 1997; p. 499).

Native range:  Nearly cosmopolitan in fresh or brackish wetlands (GRIN).

Presence:

Pacific
Country/Terr./St. &
Island group
Location Cited status &
Cited as invasive &
Cited as cultivated &
Cited as aboriginal introduction?
Reference &
Comments
French Polynesia
Clipperton Island
Clipperton (Arue, Avera) Island   Sachet, M.-H. (1962) (p. 92)
Var. latifolia A. Br.
State of Hawaii
Hawaiian Islands
O‘ahu Island introduced
invasive
Shannon, Robynn K./Wagner, Warren L. (1996) (p. 14)
Voucher cited: Limu woman 269 (US)
Probably extirpated.
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) native
U.S. Dept. Agr., Agr. Res. Serv. (2013)
Victoria, Western Australia
Australia
Australia (continental)
New South Wales native
U.S. Dept. Agr., Agr. Res. Serv. (2013)
Australia
Australia (continental)
Northern Territory   Holm, Leroy/Doll, Jerry/Holm, Eric/Pancho, Jaun/Herberger, James (1997) (p. 498)
Australia
Australia (continental)
Queensland native
U.S. Dept. Agr., Agr. Res. Serv. (2013)
China
China
China (People's Republic of) native
Zhengyi, Wu/Raven, Peter H./Deyuan, Hong (2013)
Ponds, lakes, slow-moving rivers; below 2700 m. Anhui, Guangdong, Guangxi, Hebei, Heilongjiang, Henan, Hubei, Hunan, Jiangsu, Jiangxi, Jilin, Liaoning, Nei Mongol, Shandong, Shanxi, Xinjiang, Yunnan, Zhejiang
Ecuador (Mainland)
Ecuador
Ecuador (Republic of) (continental)   Holm, Leroy/Doll, Jerry/Holm, Eric/Pancho, Jaun/Herberger, James (1997) (p. 498)
El Salvador
El Salvador
El Salvador (Republic of) native
U.S. Dept. Agr., Agr. Res. Serv. (2013)
Guatemala
Guatemala
Guatemala (Republic of) native
U.S. Dept. Agr., Agr. Res. Serv. (2013)
Indonesia
Indonesia
Indonesia (Republic of)   Holm, Leroy/Doll, Jerry/Holm, Eric/Pancho, Jaun/Herberger, James (1997) (p. 498)
Japan
Japan
Japan (country)   Holm, Leroy/Doll, Jerry/Holm, Eric/Pancho, Jaun/Herberger, James (1997) (p. 498)
North Korea
North Korea
North Korea (Democratic People's Republic of) native
U.S. Dept. Agr., Agr. Res. Serv. (2013)
South Korea
South Korea
South Korea (Republic of) native
U.S. Dept. Agr., Agr. Res. Serv. (2013)
Mexico
Mexico
Mexico (United Mexican States) native
U.S. Dept. Agr., Agr. Res. Serv. (2013)
Yucatan
Panama
Panama
Panama (Republic of) native
U.S. Dept. Agr., Agr. Res. Serv. (2013)
Taiwan
Taiwan Island
Taiwan Island native
Zhengyi, Wu/Raven, Peter H./Deyuan, Hong (2013)
Ponds, lakes, slow-moving rivers; below 2700 m.
Thailand
Thailand
Thailand (Kingdom of)   Holm, Leroy/Doll, Jerry/Holm, Eric/Pancho, Jaun/Herberger, James (1997) (p. 498)
United States (west coast)
United States (west coast states)
USA (California) native
U.S. Dept. Agr., Agr. Res. Serv. (2013)
Also reported from
Country/Terr./St. &
Island group
Location Cited status &
Cited as invasive &
Cited as cultivated &
Cited as aboriginal introduction?
Reference &
Comments
United States (continental except west coast)
United States (other states)
United States (other states) native
U.S. Dept. Agr., Agr. Res. Serv. (2013)
United States (continental except west coast)
United States (other states)
USA (Florida) native
U.S. Dept. Agr., Agr. Res. Serv. (2013)

Control:  Information on control from the Mississippi State University Extension Service.


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

  [   PIER species lists  ]   [   PIER home  ]

This page was created on 26 JAN 2007 and was last updated on 4 DEC 2010.