Conyza bonariensis (L.) Cronquist, Asteraceae

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Present on Pacific Islands?  yes

Threat only at high elevations?  no

Other Latin names:  Erigeron bonariense L.; Erigeron floribundus Schultz-Bip.

Common name(s): [more details]

English: bonar horseweed, flax-leaf fleabane, hairy fleabane, hairy horseweed, large horseweed, wavy-leaf fleabane

Hawaiian: lani wela

Habit:  herb

Description:  "Annual herb to 50 cm high or more, pubescent, with the lower leaves oblanceolate, more or less coarsely dentate; upper leaves linear; heads in racemes or racemose panicles; involucre gray-pubescent, about 5 mm long; ray-florets usually rather many, white, with the corolla shorter than the pappus"  (Stone, 1970; pp. 576-577).

"Plants 1-10 (-15) dm tall, often branched near base or unbranched, densely pubescent.  Leaves numerous, usually grayish green, lower ones up to 15 cm long and 2 cm wide, becoming progressively smaller upward, usually 3-6 cm long and 0.5-1 cm wide, coarsely serrate.  Heads usually numerous; involucre 4-6 mm high, densely pubescent; ray florets 50-200 or more per head, pistillate, rays ca. 0.5 mm long; pappus yellowish brown to reddish, in a single series, usually shorter than or equaling the inner florets"  (Wagner et al., 1999; p. 288).

Similar species: Conyza sumatrensis

Key to the species (Smith, 1991; pp. 307-308):

C. bonariensis: "Newly exposed receptacles of old heads (2-) 2.5-4.5 mm across, not angular pitted or rarely with 2-3 pits in centre; mature heads 5-6 mm long."

C. sumatrensis:  "Newly exposed receptacles of old heads usually 1.5-2.5 (-3) mm across, angular pitted with projecting points at the angles, sometimes pits and pit margins eroded with age; mature heads 4-5 mm long."

Habitat/ecology:  In Hawai‘i, "a common weed in various urban and nonurban areas, generally in relatively dry habitats, sometimes in disturbed mesic to wet forest" (Wagner et al., 1999; p. 288).

Propagation:  Seed

Native range:  Perhaps native to South America (Wagner et al., 1999; p. 288).

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		Swarbrick, John T. (1997) (p. 90)
American Samoa Tutuila Islands	Tutuila Island		Whistler, W. A. (1988) (p. 9) Rare per Whistler
American Samoa Tutuila Islands	Tutuila Island		Anon. (1988) (p. 1)
Australia (Pacific offshore islands) Lord Howe Island	Lord Howe Island	introduced	Pickard, J. (1984) (p. 205)
Australia (Pacific offshore islands) Lord Howe Island	Lord Howe Island	introduced invasive	Orchard, Anthony E., ed. (1994) (p. 18) "A cosmopolitan weed". Vouchers cited: J. Pickard 2751 (NSW); J. Pickard 2795 (NSW); 1898, J.H. Maiden (NSW); 1920, J.L. Boorman (NSW)
Australia (Pacific offshore islands) Norfolk Islands	Norfolk Island	introduced invasive	Orchard, Anthony E., ed. (1994) (p. 7) "A cosmopolitan weed". Vouchers cited: J.D. McComish 138 (K), R.O. Gardner 5768 (AK)
Commonwealth of the Northern Mariana Islands (US) Northern Mariana Islands	Pagan Island	introduced	Fosberg, F. R./Sachet, Marie-Hélène/Oliver, Royce (1979) (p. 285)
Commonwealth of the Northern Mariana Islands (US) Northern Mariana Islands	Pagan Island	introduced invasive	Fosberg, F. R./Falanruw, M. V. C./Sachet, M.-H. (1975) (p. 42) Vouchers cited: Moore 375 (US), Moore 310 (US)
Commonwealth of the Northern Mariana Islands (US) Northern Mariana Islands	Saipan Island	introduced	Raulerson, L. (2006) (p. 67)
Cook Islands Southern Cook Islands	Ma‘uke Island		McCormack, Gerald (2008) ?
Ecuador (Galápagos Islands) Fernandina Group	Fernandina Island	introduced invasive	Charles Darwin Research Station (2005)
Ecuador (Galápagos Islands) Floreana Group	Floreana Island	introduced invasive	Charles Darwin Research Station (2005)
Ecuador (Galápagos Islands) Isabela Group	Volcan Alcedo	introduced invasive	Charles Darwin Research Station (2005)
Ecuador (Galápagos Islands) Isabela Group	Volcan Cerro Azul	introduced invasive	Charles Darwin Research Station (2005)
Ecuador (Galápagos Islands) Isabela Group	Volcan Sierra Negra	introduced invasive	Charles Darwin Research Station (2005)
Ecuador (Galápagos Islands) San Cristóbal Group	San Cristóbal Island	introduced invasive	Charles Darwin Research Station (2005)
Ecuador (Galápagos Islands) Santa Cruz Group	Santa Cruz Island	introduced invasive	Charles Darwin Research Station (2005)
Ecuador (Galápagos Islands) Santiago Group	Santiago Island	introduced invasive	Charles Darwin Research Station (2005)
Fiji Fiji Islands	Fiji Islands	introduced invasive	Smith, Albert C. (1991) (pp. 307-308) See Conyza sumatrensis
French Polynesia Clipperton Island	Clipperton (Arue, Avera) Island		Sachet, M.-H. (1962) (p. 93)
French Polynesia Marquesas Islands	Eiao Island	introduced invasive	Lorence, David H./Wagner, Warren L. (2008)
French Polynesia Society Islands	Huahine Island	introduced invasive	Welsh, S. L. (1998) (p. 73) Voucher cited: Fosberg 61142
French Polynesia Society Islands	Maupiti (Maurua) Island	introduced invasive	Fosberg, F. R./Sachet, M.-H. (1987) (p. 68) Voucher cited: Fosberg 64869 (US)
French Polynesia Society Islands	Moorea Island	introduced invasive	Welsh, S. L. (1998) (p. 73) Voucher cited: C. Cartier 150
French Polynesia Society Islands	Raiatea (Havai) Island	introduced invasive	Welsh, S. L. (1998) (p. 73) Vouchers cited: Moore 381, BRY 26465
French Polynesia Society Islands	Taha‘a Island	introduced	Fosberg, F. R. (1997) (p. 16)
French Polynesia Society Islands	Tahiti Island	introduced invasive	Welsh, S. L. (1998) (p. 73) Vouchers cited: Florence 6960, Grant 3545
French Polynesia Society Islands	Tetiaroa Atoll	introduced invasive	Sachet, M.-H./Fosberg, F. R. (1983) (p. 53) Vouchers cited: Fosberg 54587 (US), Fosberg 63775 (US), Raynal 18020 (P)
French Polynesia Society Islands	Tupai (Tubai) Island	introduced invasive	Sachet, M.-H. (1983) (p. 24) Voucher cited: Sachet 1990 (US)
Guam Guam Island	Guam Island	introduced invasive	Stone, Benjamin C. (1970) (pp. 576-577)
Guam Guam Island	Guam Island	introduced	Fosberg, F. R./Sachet, Marie-Hélène/Oliver, Royce (1979) (p. 285)
State of Hawaii Hawaiian Islands	French Frigate Shoals	introduced invasive	Wagner, Warren L./Herbst, Derral R./Sohmer, S. H. (1999) (p. 288)
State of Hawaii Hawaiian Islands	Hawai‘i (Big) Island	introduced invasive	Wagner, Warren L./Herbst, Derral R./Sohmer, S. H. (1999) (p. 288)
State of Hawaii Hawaiian Islands	Kaho‘olawe Island	introduced invasive	Wagner, Warren L./Herbst, Derral R./Sohmer, S. H. (1999) (p. 288)
State of Hawaii Hawaiian Islands	Kaua‘i Island	introduced invasive	Wagner, Warren L./Herbst, Derral R./Sohmer, S. H. (1999) (p. 288)
State of Hawaii Hawaiian Islands	Kure Atoll	introduced invasive	Wagner, Warren L./Herbst, Derral R./Sohmer, S. H. (1999) (p. 288)
State of Hawaii Hawaiian Islands	Lāna‘i Island	introduced invasive	Wagner, Warren L./Herbst, Derral R./Sohmer, S. H. (1999) (p. 288)
State of Hawaii Hawaiian Islands	Laysan Island	introduced invasive	Wagner, Warren L./Herbst, Derral R./Sohmer, S. H. (1999) (p. 288)
State of Hawaii Hawaiian Islands	Lehua Island	introduced invasive	Wood, K. R./LeGrande, Maya (2006) (p. 20)
State of Hawaii Hawaiian Islands	Maui Island	introduced invasive	Wagner, Warren L./Herbst, Derral R./Sohmer, S. H. (1999) (p. 288)
State of Hawaii Hawaiian Islands	Moloka‘i Island	introduced invasive	Wagner, Warren L./Herbst, Derral R./Sohmer, S. H. (1999) (p. 288)
State of Hawaii Hawaiian Islands	Ni‘ihau Island	introduced invasive	Wagner, Warren L./Herbst, Derral R./Sohmer, S. H. (1999) (p. 288)
State of Hawaii Hawaiian Islands	O‘ahu Island	introduced invasive	Wagner, Warren L./Herbst, Derral R./Sohmer, S. H. (1999) (p. 288)
Japan (offshore islands) Bonin (Ogasawara) Islands	Bonin (Ogasawara) Islands	introduced	Kato, Hidetoshi (2007)
Japan (offshore islands) Marcus Island	Marcus Island (Minami Tori Shima)	introduced	Fosberg, F. R./Sachet, Marie-Hélène/Oliver, Royce (1979) (p. 285)
Kiribati Line Islands	Tabuaeran (Fanning) Atoll	introduced	Wester, Lyndon (1985) (p. 33)
Kiribati Tungaru (Gilbert) Islands	Butaritari Atoll	introduced	Fosberg, F. R./Sachet, Marie-Hélène/Oliver, Royce (1979) (p. 285)
Kiribati Tungaru (Gilbert) Islands	Tarawa Atoll	introduced	Fosberg, F. R./Sachet, Marie-Hélène/Oliver, Royce (1979) (p. 285)
Marshall Islands Ralik Chain	Enewetak (Ãnewetak) Atoll	introduced	Fosberg, F. R./Sachet, Marie-Hélène/Oliver, Royce (1979) (p. 285)
Marshall Islands Ralik Chain	Enewetak (Ãnewetak) Atoll	introduced invasive	St. John, Harold (1960) (p. 334) Voucher cited: St. John 23708
Marshall Islands Ralik Chain	Kwajalein (Kuwajleen) Atoll	introduced	Fosberg, F. R./Sachet, Marie-Hélène/Oliver, Royce (1979) (p. 285)
Marshall Islands Ralik Chain	Kwajalein (Kuwajleen) Atoll	introduced invasive	Whistler, W. A./Steele, O. (1999) (pp. 33-34) Vouchers cited: Fosberg 31168, Fosberg 31171
Marshall Islands Ralik Chain	Kwajalein (Kuwajleen) Atoll	introduced invasive	Fosberg, F. R. (1955) (p. 21) Vouchers cited: Fosberg 31168 (US), Fosberg 31171 (US)
Nauru Nauru Island	Nauru Island	introduced invasive	Thaman, R. R./Fosberg, F. R./Manner, H. I./Hassall, D. C. (1994) (p. 99) Voucher cited: Scully 133N (US)
New Caledonia Hunter Island	Île Hunter	introduced	MacKee, H. S. (1994) (pp. 33-34) Voucher cited: Monzier in Veillon 6929
New Caledonia Îles Loyauté (Loyalte Islands)	Îles Loyauté (Loyalty Islands)	introduced invasive	Tassin, Jacques (2005)
New Caledonia Îles Loyauté (Loyalte Islands)	Îles Ouvéa (Ouvea Atoll)	introduced	MacKee, H. S. (1994) (pp. 33-34) Voucher cited: Däniker 2048
New Caledonia Îles Loyauté (Loyalte Islands)	Île Walpole	introduced	MacKee, H. S. (1994) (pp. 33-34) Voucher cited: Hmakone & Sam in MacKee 25825
New Caledonia Matthew Island	Île Matthew	introduced	MacKee, H. S. (1994) (pp. 33-34) Voucher cited: Douheret in MacKee 38662
New Caledonia New Caledonia	New Caledonia Islands	introduced invasive	Gargominy, Oliver/Bouchet, Philipe/Pascal, Michel/Jaffre, Tanguy/Tourneu, Jean-Christophe (1996) (p. 379) Rudérale, nombreuses localités
New Caledonia New Caledonia Archipelago	Île Grande Terre	introduced invasive	Tassin, Jacques (2005)
New Caledonia New Caledonia Archipelago	Île Grande Terre	introduced	MacKee, H. S. (1994) (pp. 33-34) Vouchers cited: Vieillard 791, Melle Kiener 3 s.loc., Brousmiche 183 s.loc., Veilon 3415 (NOU), MacKee 45573
New Caledonia New Caledonia Archipelago	Île des Pins (Isle of Pines)	introduced invasive	Tassin, Jacques (2005)
New Caledonia New Caledonia Archipelago	Île des Pins (Isle of Pines)	introduced	MacKee, H. S. (1994) (pp. 33-34) Voucher cited: Germain s.n.
New Zealand (offshore islands) Kermadec Islands	Kermadec Islands	introduced invasive	Webb, C. J./Sykes, W. R./Garnock-Jones, P. J. (1988) (p. 189) "Waste places, especially stony sites, cultivated land".
New Zealand (offshore islands) Kermadec Islands	Raoul Island	introduced invasive	Sykes, W. R. (1977) (p. 87)
Niue Niue	Niue Island	introduced invasive	Whistler, W. A./Atherton, J. (1997) (p. 26)
Niue Niue	Niue Island	introduced invasive	Space, James C./Waterhouse, Barbara M./Newfield, Melanie/Bull, Cate (2004) (p. 41)
Palau Palau (main island group)	Angaur Island	introduced	Fosberg, F. R./Sachet, Marie-Hélène/Oliver, Royce (1979) (p. 285)
Palau Palau (main island group)	Babeldaob Island	introduced	Fosberg, F. R./Sachet, Marie-Hélène/Oliver, Royce (1979) (p. 285)
Palau Palau (main island group)	Peleliu Island	introduced	Fosberg, F. R./Sachet, Marie-Hélène/Oliver, Royce (1979) (p. 285)
Pitcairn Islands Pitcairn Islands	Pitcairn Island	introduced invasive	Fosberg, F. R./Paulay, Gustav/Spencer, T./Oliver, Royce (1989) (p. 15) Voucher cited: Paulay, Spencer & Schuster 661 (US)
Samoa Western Samoa Islands	Western Samoa Islands		Swarbrick, John T. (1997) (p. 90)
Solomon Islands Solomon Islands	Solomon Islands		Swarbrick, John T. (1997) (p. 90)
Tonga Ha‘apai Group	Ha‘apai Islands		Whistler, W. A. (1992) (p. 8) Voucher cited: Soakai 532
Tonga Ha‘apai Group	Tofua Island		Whistler, W. A. (1992) (p. 8) Voucher cited: Soakai 76
Tonga Tongatapu Group	Tongatapu Island		Whistler, W. A. (1992) (p. 8) Vouchers cited: Graeffe 1428, Soakai 558
Tonga Vava‘u Group	Vava‘u Island		Whistler, W. A. (1992) (p. 8) Voucher cited: Harvey s.n., Soakai 887
United States (other Pacific offshore islands) Johnston Atoll	Johnston Island	introduced invasive	Amerson, A. Binion, Jr./Shelton, Philip C. (1976) (p. 60)
United States (other Pacific offshore islands) Midway Atoll	Midway Atoll	introduced invasive	Wagner, Warren L./Herbst, Derral R./Sohmer, S. H. (1999) (p. 288)
United States (other Pacific offshore islands) Palmyra Atoll	Palmyra Atoll	introduced	Wester, Lyndon (1985) (p. 33)
United States (other Pacific offshore islands) Wake Islands	Wake Island	introduced invasive	Fosberg, F. R. (1959) (p. 19) Rare along roadsides. Voucher cited: Fosberg 34463.
United States (other Pacific offshore islands) Wake Islands	Wake Island	introduced invasive	Fosberg, F. R./Sachet, M.-H. (1969) (p. 15) Common in places. Voucher cited: Sachet 897 (US)
United States (other Pacific offshore islands) Wake Islands	Wake Island	introduced invasive	Fosberg, F. R. (1955) (p. 21) Voucher cited: Fosberg 34463 (US)

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)		Holm, Leroy/Pancho, Juan V./Herberger, James P./Plucknett, Donald L. (1979) (p. 147)
Colombia Colombia	Colombia (Republic of)		Holm, Leroy/Pancho, Juan V./Herberger, James P./Plucknett, Donald L. (1979) (p. 98)
Japan Japan	Japan (country)		Holm, Leroy/Pancho, Juan V./Herberger, James P./Plucknett, Donald L. (1979) (p. 147)
New Zealand New Zealand	New Zealand (country)	introduced invasive	Webb, C. J./Sykes, W. R./Garnock-Jones, P. J. (1988) (p. 189) "Waste places, especially stony sites, cultivated land".
Perú Perú	Perú (Republic of)		Holm, Leroy/Pancho, Juan V./Herberger, James P./Plucknett, Donald L. (1979) (p. 98)

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 invasive	Swarbrick, J. T. (1997) (p. 110)
Australia (Indian Ocean offshore islands) Cocos (Keeling) Islands	Cocos (Keeling) Islands	introduced invasive	Orchard, Anthony E., ed. (1993) (p. 37)
Maldives Maldive Islands	Addu Atoll		Spicer, R. A./Newberry, D. MacC. (1979) (p. 12)

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

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

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

Other Latin names:  Erigeron bonariense L.; Erigeron floribundus Schultz-Bip.

References:

Amerson, A. Binion, Jr./Shelton, Philip C. 1976. The natural history of Johnston Atoll. Atoll Research Bulletin No. 192. Smithsonian Institution, Washington. 479 pp.

Anon. 1988. Weed list for American Samoa by cropping system. Checklist dated 07/13/88, origin unknown. 3 pp.

Charles Darwin Research Station. 2005. CDRS Herbarium records.

Fosberg, F. R. 1955. Northern Marshall Islands Expedition, 1951-1952. Land biota: vascular plants. Atoll Research Bulletin No. 39. Pacific Science Board, National Academy of Sciences, Washington. 22 pp.

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. 1997. Preliminary checklist of the flowering plants and ferns of the Society Islands. Ed. by David R. Stoddart. U. Cal. Berkeley.

Fosberg, F. R./Falanruw, M. V. C./Sachet, M.-H. 1975. Vascular flora of the northern Marianas Islands. Smithsonian Contrib. Bot. 22:1-45.

Fosberg, F. R./Paulay, Gustav/Spencer, T./Oliver, Royce. 1989. New collections and notes on the plants of Henderson, Pitcairn, Oeno, and Ducie Islands. Atoll Research Bulletin No. 329. Smithsonian Institution, Washington. 18 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, M.-H. 1987. Flora of Maupiti, Society Islands. The Smithsonian Institution. Atoll Research Bulletin 294:1-70.

Fosberg, F. R./Sachet, Marie-Hélène/Oliver, Royce. 1979. A geographical checklist of the Micronesian dicotyledonae. Micronesica 15:1-295.

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.

Holm, Leroy/Pancho, Juan V./Herberger, James P./Plucknett, Donald L. 1979. A geographical atlas of world weeds. John Wiley & Sons, New York. 391 pp.

Kato, Hidetoshi. 2007. Herbarium records of Makino Herbarium, Tokyo Metropolitan University. Personal communication.

Lorence, David H./Wagner, Warren L. 2008. Flora of the Marquesas Islands. National Tropical Botanical Garden and the Smithsonian Institution. Online database.

MacKee, H. S. 1994. Catalogue des plantes introduites et cultivées en Nouvelle-Calédonie. Muséum National d'Histoire Naturelle, Paris, 164 p.

McCormack, Gerald. 2008. Cook Islands Biodiversity Database, Version 2007.2. Cook Islands Natural Heritage Trust, Rarotonga.

Orchard, Anthony E., ed. 1993. Flora of Australia. Vol. 50, Oceanic islands 2. Australian Government Publishing Service, Canberra.

Orchard, Anthony E., ed. 1994. Flora of Australia. Vol. 49, Oceanic islands 1. Australian Government Publishing Service, Canberra.

Pickard, J. 1984. Exotic plants on Lord Howe Island: Distribution in space and time, 1853-1981. J. of Biogeography 11:181-208.

Raulerson, L. 2006. Checklist of Plants of the Mariana Islands. University of Guam Herbarium Contribution 40:1-69. .

Sachet, M.-H. 1962. Geography and land ecology of Clipperton Island. Atoll Research Bulletin No. 86. Pacific Science Board, National Academy of Sciences, Washington. 115 pp.

Sachet, M.-H. 1983. Botanique de l'ile de Tupai, Iles de la Societe. Atoll Research Bulletin No. 276. Smithsonian Institution, Washington. 26 pp. + photos.

Sachet, M.-H./Fosberg, F. R. 1983. An ecological reconnaissance of Tetiaroa Atoll, Society Islands. Atoll Research Bulletin No. 275. Smithsonian Institution, Washington. 67 pp. + photos.

Smith, Albert C. 1991. Flora Vitiensis nova: a new flora of Fiji. National Tropical Botanical Garden, Lawai, Kauai, Hawaii. Volume 5. 626 pp.

Space, James C./Waterhouse, Barbara M./Newfield, Melanie/Bull, Cate. 2004. Report to the Government of Niue and the United Nations Development Programme: Invasive plant species on Niue following Cyclone Heta. UNDP NIU/98/G31 - Niue Enabling Activity. 80 pp.

Spicer, R. A./Newberry, D. MacC. 1979. The terrestrial vegetation of an Indian Ocean coral islands: Wilingili, Addu Atoll, Maldive Islands. I. Transect analysis of the vegetation. II. A limited quantitative analysis of the vegetation distribution. Atoll Research Bulletin 231. The Smithsonian Institution, Washington, D. C. 25 pp.

St. John, Harold. 1960. Flora of Eniwetok Atoll. Pacific Science 14(4):313-336.

Stone, Benjamin C. 1970. The flora of Guam. Micronesica 6:1-659.

Swarbrick, J. T. 1997. Environmental weeds and exotic plants on Christmas Island, Indian Ocean: a report to Parks Australia. 101 pp. plus appendix.

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

Sykes, W. R. 1977. Kermadec Islands flora: an annotated checklist. New Zealand Department of Scientific and Industrial Research Bulletin 219, Wellington. 216 pp.

Tassin, Jacques. 2005. Jacques Tassin (IAC-CIRAD), personal communication.

Thaman, R. R./Fosberg, F. R./Manner, H. I./Hassall, D. C. 1994. The flora of Nauru. Smithsonian Institution, Washington. Atoll Research Bulletin 392:1-223.

U. S. Government. 2006. Integrated Taxonomic Information System (ITIS) (on-line resource).

U.S. Dept. Agr., Agr. Res. Serv. 2008. National Genetic Resources Program. Germplasm Resources Information Network (GRIN). Online searchable database.

Wagner, Warren L./Herbst, Derral R./Sohmer, S. H. 1999. Manual of the flowering plants of Hawaii. Revised edition. Bernice P. Bishop Museum special publication. University of Hawai‘i Press/Bishop Museum Press, Honolulu. 1919 pp. (two volumes).

Webb, C. J./Sykes, W. R./Garnock-Jones, P. J. 1988. Flora of New Zealand, Volume IV: Naturalised pteridophytes, gymnosperms, dicotyledons. Botany Division, DSIR, Christchurch. 1365 pp.

Welsh, S. L. 1998. Flora Societensis: A summary revision of the flowering plants of the Society Islands. E.P.S. Inc., Orem, Utah. 420 pp.

Wester, Lyndon. 1985. Checklist of the vascular plants of the northern Line Islands. Smithsonian Institution, Washington. Atoll Reseach Bulletin 287:1-38.

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

Whistler, W. A. 1992. Flora of Tonga [unpublished checklist]. 107 pp.

Whistler, W. A./Atherton, J. 1997. Botanical survey of the Huvalu Forest Conservation Area, Niue. Unpublished technical report. 76 pp.

Whistler, W. A./Steele, O. 1999. Botanical survey of the United States of America Kwajalein Atoll (USAKA) Islands. Prepared for Oak Ridge Institute for Science and Education and the U. S. Army Environmental Center. 111 pp.

Wiggins, I. L./Porter, D. M. 1971. Flora of the Galapágos Islands. Stanford University Press. 998 pp.

Wood, K. R./LeGrande, Maya. 2006. An annotated checklist and new island records of flowering plants from Lehua Islet, Ni‘ihau, Hawai‘i. In: Evenhuis, Neal L. and Eldredge, Lucias G., eds. Records of the Hawaii Biological Survey for 2004-2005. Part 1: Articles. Bishop Museum Occasional Papers 87:19-29.