Eichhornia crassipes (Mart.) Solms, Pontederiaceae

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Present on Pacific Islands?  yes

Primarily a threat at high elevations?  no

Risk assessment results:  High risk, score: 26 (Go to the risk assessment)

Common name(s): [more details]

Chinese: feng yan lan

English: Nile lily, water hyacinth

Fijian: bekabekairaga, dabedabe ne ga, mbekambekairanga, ndambendambe ni nga

French: jacinthe d'eau, pensée d'eau

Hindi: jal khumbe

Japanese: hoteiaoi

Maori (Cook Islands): riri vai

Palauan: bung el ralm

Samoan: lili vai, lili vai

Spanish: aguapey, buchon, calamote, jacinto aquático, jacinto de agua, jacinto de rio, lechuguilla, liro de agua, tarulla

Habit:  aquatic herb

Description:  "A perennial aquatic herb; stems short, floating or rooting in mud, rhizomatous or stoloniferous, rooting from the nodes; roots long, sometimes dark because of their purple anthocyanin, pendant; leaves in a rosette; petioles spongy, in young specimens short and with a one-sided swelling or inflation but up to 30 cm long when older, tapering and narrowing from the bulbous base to the point of attachment with the lamina; lamina circular to kidney-shaped, glossy smooth, 4 to 15 cm long and wide, acting as a sail in the wind; inflorescence in spikes with about eight flowers, long peduncled, bibracteate, the lower bract with long sheath and small lamina, the upper almost entirely included within the sheath of the lower one, tubular with a small pointed tip (apiculate); flower-bearing part of the rachis up to 15 cm or less long; entire scape may be 30 cm; perianth six-lobed, united below into a narrow tube, lilac, bluish purple or white, the upper lobe bearing a violet blotch with yellow center; stamens six, three long, three shorter, attached to the tube; capsule membranous, three-locular, dehiscent, many-seeded, as many as 50 or so per capsule; seed ovoid, ribbed, 0.5 to 1 mm.  The species is distinguished by the almost one-sided swelling or inflation of the petiole, its long peduncled bibracteate spike, and its upper perianth blotched with yellow at the center"  (Holm et al., 1977; p. 72).

"Rooted only at flowering time by long slender roots; otherwise floating, with thick, fleshy, more or less horizontal roots; leaves clustered, on bulbously inflated petioles, blades rounded or oblong, up to 3-4 inches wide; flowers showy, pale violet with a spot of bright yellow on the large upper lobe, some forms with pink and yellow flowers, all parts edible" (Stone, 1970; p. 116).

Habitat/ecology:  Freshwater lakes, ponds, marshes, ditches, canals, slow-moving streams.  "It is an aquatic floating weed. It does not tolerate brackish water (Holm et al., 1977; pp. 72-77) and salinity can limit or modify its distribution. For example, water hyacinth, which accumulates in the coastal lagoons of West Africa during the wet season, is reduced in those areas which become saline during the dry season. Growth by water hyacinth is favored by nutrient rich water, in particular by nitrogen, phosphorus and potassium" (Ecoport). "High growth rates mean populations can quickly form thick mats on the water surface.  This makes passage by boats difficult, chokes irrigation channels, pollutes water and provides breeding grounds for disease-carrying insects.  The natural beauty of areas is also degraded as native plants, birds and fish are displaced."  (Smith, 2002; p. 82).

In Hawai‘i, "introduced as an ornamental, now naturalized and locally abundant in standing or slow-moving water such as ponds and sluggish streams at low elevations"  (Wagner et al., 1999; pp. 1604-1606).  In Fiji, "a locally abundant adventive, occurring near sea level (but elsewhere up to an elevation of 1,600 m or higher)"  (Smith, 1979; pp. 175-176). In New Caledonia, "peu cultivée à présent, existe en masses serrées là où des rivières à courant faible ou des mares lui offerent des stations favorables mais n'obstrue pas les cours d'eau autant qu'en d'autres pays tropicaux" (MacKee, 1994; p. 118). In New Zealand, "An established escape from ponds and aquaria, now eradicated from many localities. E. crassipes was originally introduced as an ornamental, but it both accidentally escaped from cultivation and was deliberately planed, and by 1950 was established and troublesome in dams, ponds, swamps, slow-moving streams and river cut-offs in the Auckland Province" Possession of the plant in New Zealand is illegal (Healy & Edgar, 1980; p. 60).

Propagation:  "Water hyacinth reproduces vegetatively by means of stolons which, together with solitary plants or drifting mats, are readily distributed by water currents, wind, boats and rafts. The plant also produces vast quantities of long-lived seed and persistence and spread by this means can be very significant (Sculthorpe 1971)." (Ecoport).  "Spread throughout its range by intentional introductions as an ornamental" (Smith, 2002; p. 82).

Native range:  Amazon basin, now introduced and cultivated in most warm countries.

Presence:

Pacific
Country/Terr./St. & Island group	Location	Cited status & Cited as invasive & Cited as cultivated & Cited as aboriginal introduction?	Reference & Comments
American Samoa Tutuila Islands	Tutuila Island	introduced invasive	Space, James C./Flynn, Tim (2000) (p. 35)
Australia (Pacific offshore islands) Norfolk Islands	Norfolk Island	introduced invasive	Orchard, Anthony E., ed. (1994) (p. 12) "Common in open fresh-water habitats". Sight record, 1983, P.S. Green.
Commonwealth of the Northern Mariana Islands (US) Northern Mariana Islands	Rota Island	introduced	Fosberg, F. R./Sachet, Marie-Hélène/Oliver, Royce (1987) (p. 99)
Commonwealth of the Northern Mariana Islands (US) Northern Mariana Islands	Saipan Island	introduced	Fosberg, F. R./Sachet, Marie-Hélène/Oliver, Royce (1987) (p. 99)
Cook Islands Southern Cook Islands	Mangaia Island		McCormack, Gerald (2011)
Cook Islands Southern Cook Islands	Rarotonga Island	introduced invasive	Meyer, Jean-Yves (2000) (p. 89)
Cook Islands Southern Cook Islands	Rarotonga Island		McCormack, Gerald (2011)
Federated States of Micronesia Chuuk Islands	Chuuk Islands	introduced	Space, James C./Waterhouse, Barbara/Denslow, Julie S./Nelson, Duane/Mazawa, Thomas R. (2000) (p. 27)
Federated States of Micronesia Kosrae Island	Kosrae Island	introduced cultivated	Lorence, David H./Flynn, Timothy (2010) (p. 11) "Apparently not yet naturalized".
Federated States of Micronesia Pohnpei Islands	Pohnpei Island	introduced	Fosberg, F. R./Sachet, Marie-Hélène/Oliver, Royce (1987) (p. 99)
Federated States of Micronesia Pohnpei Islands	Pohnpei Island	introduced invasive	Meyer, Jean-Yves (2000) (p. 90)
Federated States of Micronesia Pohnpei Islands	Pohnpei Island	introduced	Glassman, S. F. (1952) (pp. 107-108) Voucher cited: Glassman 2553 (US)
Federated States of Micronesia Pohnpei Islands	Pohnpei Island	introduced cultivated	Herrera, Katherine/Lorence, David H./Flynn, Timothy/Balick, Michael J. (2010) (p. 62) Vouchers cited: F.R. Fosberg 26257 (BISH), S.F. Glassman 2553 (BISH), L. Stemmermann 2979 (BISH), M. Takamatsu 908 (BISH), M. Takamatsu 910 (BISH)
Federated States of Micronesia Yap Islands	Yap (Waqab) Island	introduced	Fosberg, F. R./Sachet, Marie-Hélène/Oliver, Royce (1987) (p. 99)
Fiji Fiji Islands	Viti Levu Island	introduced invasive cultivated	Smith, Albert C. (1979) (pp. 175-176) Vouchers cited: Greenwood 184, Vaughan 3161, DA 11013, DA 9462, DA 3991, DA 3992, DA 6085, DA 3481
French Polynesia Marquesas Islands	Ua Pou (Huapu, Uapou, Uapu) Island	introduced invasive	Lorence, David H./Wagner, Warren L. (2008) Voucher cited: S. P. Perlman, E. Vogt 15889 (PTBG)
French Polynesia Marquesas Islands	Ua Pou (Huapu, Uapou, Uapu) Island	introduced invasive	Florence, J./Chevillotte, H./Ollier, C./Meyer, J.-Y. (2011) Naturalisée
French Polynesia Society Islands	Raiatea (Havai) Island	introduced invasive	Welsh, S. L. (1998) (p. 376)
French Polynesia Society Islands	Raiatea (Havai) Island	introduced invasive	Florence, J./Chevillotte, H./Ollier, C./Meyer, J.-Y. (2011) Naturalisée
French Polynesia Society Islands	Tahiti Island	introduced invasive	Welsh, S. L. (1998) (p. 376) Vouchers cited: Setchell & Parks 238, Florence 2557, BRY 25445
French Polynesia Society Islands	Tahiti Island	introduced invasive	Florence, J./Chevillotte, H./Ollier, C./Meyer, J.-Y. (2011) Voucher cited: J. Florence 2557 (PAP) Naturalisée. Peu envahissant.
French Polynesia Society Islands	Tetiaroa Atoll	introduced cultivated	Sachet, M.-H./Fosberg, F. R. (1983) (p. 64)
French Polynesia Austral (Tubuai) Islands	Tubuai Island	introduced invasive	Florence, J./Chevillotte, H./Ollier, C./Meyer, J.-Y. (2011) Naturalisée
Guam Guam Island	Guam Island	introduced invasive	Stone, Benjamin C. (1970) (p. 116) Voucher cited: Stone 4915 (GUAM)
Guam Guam Island	Guam Island	introduced	Fosberg, F. R./Sachet, Marie-Hélène/Oliver, Royce (1987) (p. 99)
Guam Guam Island	Guam Island	introduced invasive	Meyer, Jean-Yves (2000) (p. 95)
State of Hawaii Hawaiian Islands	Hawai‘i (Big) Island	introduced invasive	Wagner, Warren L./Herbst, Derral R./Sohmer, S. H. (1999) (pp. 1604-1606)
State of Hawaii Hawaiian Islands	Kaua‘i Island	introduced invasive	Wagner, Warren L./Herbst, Derral R./Sohmer, S. H. (1999) (pp. 1604-1606)
State of Hawaii Hawaiian Islands	Maui Island	introduced invasive	Wagner, Warren L./Herbst, Derral R./Sohmer, S. H. (1999) (pp. 1604-1606)
State of Hawaii Hawaiian Islands	O‘ahu Island	introduced invasive	Wagner, Warren L./Herbst, Derral R./Sohmer, S. H. (1999) (pp. 1604-1606)
Marshall Islands Ralik Chain	Kwajalein (Kuwajleen) Atoll	introduced cultivated	Whistler, W. A./Steele, O. (1999) (p. 105)
Marshall Islands Ratak Chain	Arno Atoll	introduced cultivated	Vander Velde, Nancy/Vander Velde, Brian (2007) (p. 4) "Rare; few plants observed in container by private residence in Ine; could pose serious environmental threat if introduced into wetlands".
Marshall Islands Ratak Chain	Majuro (Mãjro) Atoll	introduced cultivated	Vander Velde, Nancy (2003) (p. 55)
Nauru Nauru Island	Nauru Island	introduced invasive cultivated	Thaman, R. R./Fosberg, F. R./Manner, H. I./Hassall, D. C. (1994) (p. 74) Voucher cited: Hassall 255 (SUVA)
New Caledonia New Caledonia	New Caledonia Islands	introduced invasive	Meyer, Jean-Yves (2000) (p. 100)
New Caledonia New Caledonia	New Caledonia Islands	introduced invasive cultivated	Gargominy, Oliver/Bouchet, Philipe/Pascal, Michel/Jaffre, Tanguy/Tourneu, Jean-Christophe (1996) (p. 382) Esiste en masses serrées dans les mares ou les rivières à faible courant mais n'obstrue pas les cours d'eau autant qu'en d'autres pays tropicaux.
New Caledonia New Caledonia Archipelago	Île Grande Terre	introduced invasive cultivated	MacKee, H. S. (1994) (p. 118) Vouchers cited: Sarasin 299 (Z), Compton 1602 (BM), Baumann & Guillaumin 9570, MacKee 4318, Jérémie & Tirel 1647
Palau Palau (main island group)	Babeldaob Island	introduced cultivated	Space, James C./Waterhouse, Barbara/Miles, Joel E./Tiobech, Joseph/Rengulbai, Kashgar (2003) (pp. 12, 85)
Palau Palau (main island group)	Koror Island	introduced	Fosberg, F. R./Sachet, Marie-Hélène/Oliver, Royce (1987) (p. 99)
Palau Palau (main island group)	Koror Island	introduced cultivated	Space, James C./Waterhouse, Barbara/Miles, Joel E./Tiobech, Joseph/Rengulbai, Kashgar (2003) (pp. 12, 80)
Palau Palau (main island group)	Koror Island	introduced cultivated	Lorence, David H./Flynn, Tim (2010) (p. 18)
Palau Palau (main island group)	Koror Island		Beleu National Museum (Republic of Palau. Koror.) (1966) (voucher ID: BNM 195) Taxon name on voucher: Eichhornia crassipes (Mart. & Zecc.) Solms
Palau Palau (main island group)	Ngerkebesang Island	introduced cultivated	Space, James C./Waterhouse, Barbara/Miles, Joel E./Tiobech, Joseph/Rengulbai, Kashgar (2003) (p. 12)
Papua New Guinea Papua New Guinea (eastern New Guinea Island)	Papua New Guinea (eastern New Guinea Island)	introduced	Henty, E. E./Pritchard, G. H. (1975) (p. 46) Introduced and eliminated several times [as of date of publication].
Papua New Guinea Papua New Guinea (eastern New Guinea Island)	Papua New Guinea (eastern New Guinea Island)		Waterhouse, D. F. (1997) (p. 61)
Philippines Philippine Islands	Philippine Islands	introduced invasive	Holm, Leroy G./Plucknett, D. L./Pancho, J. V./Herberger, J. P. (1977) (pp. 72-77)
Philippines Philippine Islands	Philippine Islands	introduced invasive cultivated	Merrill, Elmer D. (1925) (p. 200) Introduced about 1912 as an ornamental, now very abundant in shallow water of lakes and in slow streams.
Samoa Western Samoa Islands	Upolu Island	introduced invasive	Space, James C./Flynn, Tim (2002) (p. 9) Voucher: Flynn 6972 (PTBG, SAMOA)
Samoa Western Samoa Islands	Upolu Island		National Tropical Botanical Garden (U.S.A. Hawaii. Kalaheo.) (2002) (voucher ID: PTBG 306) Taxon name on voucher: Eichhornia crassipes
Solomon Islands Solomon Islands	Solomon Islands		Swarbrick, John T. (1997) (p. 91)
Solomon Islands Solomon Islands	Solomon Islands	introduced	Hancock, I. R./Henderson, C. P. (1988) (p. 70)
Solomon Islands Solomon Islands	Solomon Islands	introduced invasive cultivated	Shine, C./Reaser, J. K./Gutierrez, A. T., eds. (2003) (p. 165) Dominant invader.
United States (other Pacific offshore islands) Wake Islands	Wake Island	introduced cultivated	Fosberg, F. R. (1959) (p. 11) One plant seen in 1952.
United States (other Pacific offshore islands) Wake Islands	Wake Island	introduced	Fosberg, F. R./Sachet, M.-H. (1969) (p. 7) Not seen in 1961 or 1963.
Vanuatu New Hebrides Islands	Vanuatu (Republic of)	introduced invasive	Meyer, Jean-Yves (2000) (p. 106)
Vanuatu New Hebrides Islands	Vanuatu (Republic of)	introduced invasive	Shine, C./Reaser, J. K./Gutierrez, A. T., eds. (2003) (p. 179)

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	introduced invasive	Smith, Nicholas M. (2002) (p. 82) All infestations eradicated except for Fogg Dam where isolated outbreaks are under control.
Australia Australia (continental)	Queensland	introduced invasive	Smith, Nicholas M. (2002) (p. 82)
Cambodia Cambodia	Cambodia (Kingdom of)	introduced invasive	Holm, Leroy G./Plucknett, D. L./Pancho, J. V./Herberger, J. P. (1977) (pp. 72-77)
China China	China (People's Republic of)	introduced invasive	Holm, Leroy G./Plucknett, D. L./Pancho, J. V./Herberger, J. P. (1977) (pp. 72-77)
China China	Hong Kong	introduced invasive cultivated	Wu, Te-lin (2001) (p. 356) In ponds and rivers.
Colombia Colombia	Colombia (Republic of)	introduced invasive	Holm, Leroy G./Plucknett, D. L./Pancho, J. V./Herberger, J. P. (1977) (pp. 74, 76)
Costa Rica Costa Rica	Costa Rica (Republic of)		Holm, Leroy/Pancho, Juan V./Herberger, James P./Plucknett, Donald L. (1979) (p. 136)
Honduras Honduras	Honduras (Republic of)		Holm, Leroy/Pancho, Juan V./Herberger, James P./Plucknett, Donald L. (1979) (p. 136)
Indonesia Indonesia	Indonesia (Republic of)	introduced invasive	Holm, Leroy G./Plucknett, D. L./Pancho, J. V./Herberger, J. P. (1977) (pp. 72-77)
Japan Japan	Japan (country)	introduced invasive	Holm, Leroy G./Plucknett, D. L./Pancho, J. V./Herberger, J. P. (1977) (pp. 72-77)
Japan Japan	Japan (country)	introduced	Mito, Toshikazu/Uesugi, Tetsuro (2004) (p. 191)
South Korea South Korea	South Korea (Republic of)		Holm, Leroy/Pancho, Juan V./Herberger, James P./Plucknett, Donald L. (1979) (p. 136)
Malaysia Malaysia	Malaysia (country of)	introduced invasive	Holm, Leroy G./Plucknett, D. L./Pancho, J. V./Herberger, J. P. (1977) (pp. 72-77)
Mexico Mexico	Mexico (United Mexican States)	introduced invasive	Holm, Leroy G./Plucknett, D. L./Pancho, J. V./Herberger, J. P. (1977) (p. 75)
Negara Brunei Darussalam Brunei	Brunei (Negara Brunei Darussalam)	introduced invasive	Waterhouse, D. F. (1993) (pp. 65, 77)
New Zealand New Zealand	New Zealand (country)	introduced invasive	Healy, A. J./Edgar, E. (1980) (p. 60) Voucher cited: N. T. Moar 445 (CHR 64900)
Nicaragua Nicaragua	Nicaragua (Republic of)	introduced invasive	Holm, Leroy G./Plucknett, D. L./Pancho, J. V./Herberger, J. P. (1977) (pp. 74, 77)
Panama Panama	Panama (Republic of)		Holm, Leroy/Pancho, Juan V./Herberger, James P./Plucknett, Donald L. (1979) (p. 136)
Singapore Singapore	Singapore (Republic of)	introduced invasive	Waterhouse, D. F. (1993) (pp. 65, 77)
Singapore Singapore	Singapore (Republic of)	introduced invasive	Chong, Kwek Yan/Tan, Hugh T. W./Corlett, Richard T. (2009) (p. 38) Naturalised
Taiwan Taiwan	Taiwan Island	introduced invasive	Holm, Leroy G./Plucknett, D. L./Pancho, J. V./Herberger, J. P. (1977) (pp. 72-77)
Thailand Thailand	Thailand (Kingdom of)	introduced invasive	Holm, Leroy G./Plucknett, D. L./Pancho, J. V./Herberger, J. P. (1977) (pp. 72-77)
United States (west coast) United States (west coast states)	USA (California)	introduced invasive	Holm, Leroy G./Plucknett, D. L./Pancho, J. V./Herberger, J. P. (1977) (pp. 72-77)
Vietnam Vietnam	Vietnam (Socialist Republic of)	introduced invasive	Holm, Leroy G./Plucknett, D. L./Pancho, J. V./Herberger, J. P. (1977) (pp. 72-77)

Indian Ocean
Country/Terr./St. & Island group	Location	Cited status & Cited as invasive & Cited as cultivated & Cited as aboriginal introduction?	Reference & Comments
Australia (Indian Ocean offshore islands) Christmas Island Group	Christmas Island	introduced cultivated	Swarbrick, J. T. (1997) (p. 113)
La Réunion (France) La Réunion Island	La Réunion Island	introduced invasive	Holm, Leroy G./Plucknett, D. L./Pancho, J. V./Herberger, J. P. (1977) (pp. 72-77)
La Réunion (France) La Réunion Island	La Réunion Island	introduced invasive	Lavergne, Christophe (2006) "Envahissant"
Maldives Maldive Islands	Maldive Islands	introduced invasive	Pallawatta, Nirmalie/Reaser, Jamie K./Gutierrez, Alixis T./eds. (2003) (p. 62)
Mauritius Mautitius Islands (Mauritius and Rodrigues)	Mauritius Island	introduced invasive	Holm, Leroy G./Plucknett, D. L./Pancho, J. V./Herberger, J. P. (1977) (pp. 72-77)
Seychelles Seychelles Islands	Seychelles Islands	introduced	Weber, Ewald (2003) (p. 148)

Also reported from
Country/Terr./St. & Island group	Location	Cited status & Cited as invasive & Cited as cultivated & Cited as aboriginal introduction?	Reference & Comments
South Africa South Africa	South Africa (Republic of)	introduced invasive	Holm, Leroy G./Plucknett, D. L./Pancho, J. V./Herberger, J. P. (1977) (pp. 72-77)
United States (continental except west coast) United States (other states)	USA (Florida)	introduced invasive	Holm, Leroy G./Plucknett, D. L./Pancho, J. V./Herberger, J. P. (1977) (pp. 72-77)

Comments:  Can become so thick that it chokes lakes and rivers (Florida and Australia). A declared noxious weed in Western Australia, the Northern Territory and Queensland (Smith, 2002; p. 82). A Class A (eradicate) noxious weed in New Zealand. Can be used for pig feed, but this may aid in its spread.

Planting of this species in the State of Florida (U.S.) is prohibited by Florida Department of Environmental Protection (Hunsberger, 2001).

Control:  See "Biology and control of aquatic plants: A best management practices handbook"  for control information (large file, PDF format).  Additional control information from the Bugwood Wiki.

Physical: Hand pulling, dragline or specially designed harvesting machine.

Permanent drainage to dry out a pond or lake will control water hyacinth (Smith et al.1984).

Chemical: Herbicidal control of large infestations of water hyacinth growing under favorable conditions has been attempted only rarely (Scott et al. undated) and even when enormous resources have been invested, as in Sudan, has had little effect. However, this method has been successful for controlling small infestations accessible by land or boat (Smith et al. 1984; Jamieson et al. 1977) and eradicating small infestations in regions that are climatically unfavorable to growth of this plant. The herbicides most commonly used have been 2,4-D and Glyphosate, the first of these being by far the most widely used as it is relatively inexpensive.

The proliferation of water hyacinth in its exotic range is determined largely by two factors; nutrient supply and the absence of natural enemies of the weeds. To be fully effective, control strategies must address both watershed management and direct weed control.

The effects which the management of watersheds can have on the nutrient level of rivers, lakes and other wetlands has already been referred to. Watersheds must be managed to control water hyacinth and other floating aquatic weeds, provide a sustainable, acceptable life-style for the human population living in the watershed, and conserve the ecology and biodiversity. (GPPIS).

Biological:  "There have been many attempts at biological control, with a steadily increasing record of substantial successes, although these have generally been slow in emerging.  The most important natural enemies include two weevils (Neochetina eichhorniae and N. bruchi), two moth larvae (Sameodes albiguttalis and Haimbachia infusella), a mite (Orthogalumna terebrantis) and a fungus (Cercospora rodmanii).  However there are many other natural enemies that could be investigated if required.  Experience in a number of countries indicates that the establishment of several of the above organisms is highly likely to bring about a significant reduction in the abundance of water hyacinth.  Control is generally slow in developing and, in some situations, all of the above organisms (and perhaps even others) may be required to provide an adequate level of suppression"  (Waterhouse, 1994; p. 69).

The biological control agents which have been most successful are two weevils, Neochetina bruchi Hustache and N. eichhorniae Warner, and a moth Sameodes albiguttalis (Warren). However, optimal control has not been achieved in all situations and additional agents are being evaluated, including the moth Aeigona infusella.

Biological control information from the publication "Biological control of invasive plants in the eastern United States".

Waterhouse (1994, pp. 73-83) lists natural enemies, promising biological control agents, and a summary of attempts at biological control by country.

Additional information:
Information on the Environment Bay of Plenty, New Zealand, web site.
Fact sheet from the Bay of Plenty Regional Council, New Zealand.
Information from the Bugwood Wiki.
Photos and additional information at University of Florida, Center for Aquatic and Invasive Plants.
Photo and additional information at the University of Guam "Plants of Guam" web site.
Fact sheet from the Government of Queensland, Australia (PDF format).
Information from the Purdue University NewCROP web site.
European and Mediterranean Plant Protection Organization mini-datasheet.
Information from the Global Invasive Species Database.
Information from the Southeast Exotic Pest Plant Council Invasive Plant Manual.
Information from the book "Identification and biology of non-native plants in Florida's natural areas" (PDF format).
See information in the book "Biology and control of aquatic plants: A best management practices handbook"  (large file, PDF format).

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

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

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

References:

Beleu National Museum (Republic of Palau. Koror.). 1966. Voucher specimen #BNM195(Blackburn E-83).

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.

EcoPort Foundation. 2011. EcoPort (on-line resource).

Florence, J./Chevillotte, H./Ollier, C./Meyer, J.-Y. 2011. Base de données botaniques Nadeaud de l'Herbier de la Polynésie Française (PAP). (online resource).

Fosberg, F. R. 1959. Vegetation and flora of Wake Island. Atoll Research Bulletin 67. Pacific Science Board, National Academy of Sciences, Washington. 20 pp.

Fosberg, F. R./Otobed, D./Sachet, M.-H./Oliver, R. L./Powell, D. A./Canfield, J. E. 1980. Vascular plants of Palau with vernacular names. Department of Botany, The Smithsonian Institution, Washington, D.C. 43 pp.

Fosberg, F. R./Sachet, M.-H. 1969. Wake Island vegetation and flora, 1961-1963. Atoll Research Bulletin No. 123. Smithsonian Institution, Washington. 15 pp.

Fosberg, F. R./Sachet, Marie-Hélène/Oliver, Royce. 1987. A geographical checklist of the Micronesian monocotyledonae. Micronesica 20:1-126.

Gargominy, Oliver/Bouchet, Philipe/Pascal, Michel/Jaffre, Tanguy/Tourneu, Jean-Christophe. 1996. Conséquences des introductions d'espèces animales et végétales sur la biodiversité en Nouvelle-Calédonie. Rev. Ecol. (Terre Vie) 51:375-401.

Gettys, Lyn A./Haller, William T./Bellaud, Marc; eds. 2009. Biology and control of aquatic plants: A best management practices handbook. Aquatic Ecosystem Restoration Foundation, Marietta, Georgia. ISBN 978-0-615-32646-7. 200 pp.

Glassman, S. F. 1952. The flora of Ponape. Bishop Mus. Bull. 209: 1-152.

Hafliger, E. 1092. Monocot Weeds 3. CIBA-GEIGY Ltd., Basle, Switzerland. 132 pp. plus plates.

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