Bidens alba (L.) DC., Asteraceae

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Present on Pacific Islands?  yes

Primarily a threat at high elevations?  no

Risk assessment results:  High risk, score: 12 (Go to the risk assessment)

Other Latin names:  Bidens pilosa L. var. radiata Shultz-Bip.

Common name(s): [more details]

English: beggar's tick, burr marigold, cobbler's pegs, romerillo, shepherd's needles, Spanish needle

Nauruan: kauen oe, kawen oe

Palauan: emuul

Pohnpeian: dihpwketipwehl suwed, koionleng wah pwetepwet, moaresed, ngkahu

Habit:  herb

Description:  "Erect annual or short-lived perennial herbs 0.3-1.5 m tall.  Leaves simple or pinnately compound, usually 6-17 cm long including petiole, leaflets 1-3.  Heads 3-18 in compound cymes terminating main stem and lateral branches, 2.2-4.2 cm in diameter including ray florets, peduncles 0.8-11 cm long; outer involucral bracts spatulate-tipped, (2-) 4-5 mm long; ray florets 5-8 per head, sterile, rays white, 10-16 mm long; disk florets 26-69 per head, perfect; pappus of 2 awns 1-2 mm long. Achenes black, straight, wingless, 4-12 mm long, setose."  (Wagner et al., 1999)

Key to distinguish between Bidens alba and Bidens pilosa:

Ray florets 5-8 per head, rays 10-16 mm long:  Bidens alba
Ray florets absent or 4-7 per head, rays 2-8 mm long:  Bidens pilosa  (Wagner et al., 1999; p. 270).

Habitat/ecology:  In Hawai‘i, "in lowland disturbed area" (Wagner et al., 1999; p. 270).  On Kwajalein (Marshall Islands), "common to locally abundant in disturbed areas such as roadsides and lawns" (Whistler & Steele, 1999; p. 33). In Guam, "it is extremely common now, all over the island, not only in waste ground but sometimes at the fringes of forest, sometimes forming dense thickets nearly 1 m tall" (Stone, 1970; p. 583).

Propagation:  Seed. Barbed achenes adhere to clothing, feathers and fur.

Native range:  Florida to South America and the West Indies (Wagner et al., 1999; p. 270).

Presence:

Pacific
Country/Terr./St. & Island group	Location	Cited status & Cited as invasive & Cited as cultivated & Cited as aboriginal introduction?	Reference & Comments
American Samoa Manu‘a Islands	Ofu Island	introduced	Ragone, Diane/Lorence, David H. (2003) (p. 48) var. radiata
American Samoa Manu‘a Islands	Ofu Island		National Tropical Botanical Garden (U.S.A. Hawaii. Kalaheo.) (2001) (voucher ID: PTBG 35337) Taxon name on voucher: Bidens alba (L.) DC.
American Samoa Manu‘a Islands	Ta‘u Island		National Tropical Botanical Garden (U.S.A. Hawaii. Kalaheo.) (1990) (voucher ID: PTBG 9144) Taxon name on voucher: Bidens alba var. radiata
Commonwealth of the Northern Mariana Islands (US) Northern Mariana Islands	Rota Island	introduced	Fosberg, F. R./Sachet, Marie-Hélène/Oliver, Royce (1979) (p. 283)
Commonwealth of the Northern Mariana Islands (US) Northern Mariana Islands	Saipan Island	introduced	Raulerson, L. (2006) (p. 67)
Commonwealth of the Northern Mariana Islands (US) Northern Mariana Islands	Tinian Island	introduced	Raulerson, L. (2006) (p. 67)
Federated States of Micronesia Kosrae Island	Kosrae Island	introduced invasive	Lorence, David H./Flynn, Timothy (2010) (p. 13) Voucher cited: Lorence 7874 (PTBG) Naturalized
Federated States of Micronesia Kosrae Island	Kosrae Island	introduced invasive	Josekutty, P. C./Wakuk, E. E./Joseph, M. J. (2002) (p. 62)
Federated States of Micronesia Kosrae Island	Kosrae Island		National Tropical Botanical Garden (U.S.A. Hawaii. Kalaheo.) (1996) (voucher ID: PTBG 21063) Taxon name on voucher: Bidens alba var. radiata (L.) DC.
Federated States of Micronesia Pohnpei Islands	Pohnpei Island	introduced invasive	Herrera, Katherine/Lorence, David H./Flynn, Timothy/Balick, Michael J. (2010) (p. 72) Vouchers cited: M.J. Balick 3855 (NY, PTBG), M.J. Balick 4304 (NY, PTBG), A. Dores 187 (NY, PTBG), B. Ekiek 122 (NY, PTBG), F.R. Fosberg 58430 (BISH), N. Krauss 1881, S. Perlman 20340 (PTBG), S. Perlman 21405 (PTBG) Invasive
Federated States of Micronesia Pohnpei Islands	Pohnpei Island	introduced invasive	Fosberg, F. R./Falanruw, M. V. C. (1980) (p. 209) Voucher cited: Fosberg 58430 (US, BISH)
Federated States of Micronesia Pohnpei Islands	Pohnpei Island		National Tropical Botanical Garden (U.S.A. Hawaii. Kalaheo.) (1997) (voucher ID: PTBG 37720) Taxon name on voucher: Bidens alba (L.) DC. var. var. radiata (Sch. Bip.) Ballard ex Melchert
Federated States of Micronesia Pohnpei Islands	Pohnpei Island		National Tropical Botanical Garden (U.S.A. Hawaii. Kalaheo.) (2003) (voucher ID: PTBG 43656) Taxon name on voucher: Bidens alba
French Polynesia Marquesas Islands	Fatu Hiva Island	introduced invasive	Lorence, David H./Wagner, Warren L. (2008)
French Polynesia Marquesas Islands	Fatu Hiva Island	introduced invasive	Florence, J./Chevillotte, H./Ollier, C./Meyer, J.-Y. (2011) var. radiata (Sch.-Bip.) Ballard ex Melchert. Voucher cited: D.H. Lorence, L. Dunn, S.P. Perlman, K.R. Wood & J.-Y. Meyer 9026 (PAP) Adventice
French Polynesia Marquesas Islands	Fatu Hiva Island		National Tropical Botanical Garden (U.S.A. Hawaii. Kalaheo.) (2003) (voucher ID: PTBG 39348) Taxon name on voucher: Bidens alba var. radiata
Guam Guam Island	Guam Island	introduced invasive	Stone, Benjamin C. (1970) (p. 583) Voucher cited: Stone 5048 (GUAM)
Guam Guam Island	Guam Island	introduced	Fosberg, F. R./Sachet, Marie-Hélène/Oliver, Royce (1979) (p. 283)
State of Hawaii Hawaiian Islands	Hawai‘i (Big) Island	introduced invasive	Wagner, Warren L./Herbst, Derral R./Sohmer, S. H. (1999) (p. 270) var. radiata
State of Hawaii Hawaiian Islands	Kaho‘olawe Island	introduced invasive	Wagner, Warren L./Herbst, Derral R./Sohmer, S. H. (1999) (p. 270) var. radiata
State of Hawaii Hawaiian Islands	Kaua‘i Island	introduced invasive	Wagner, Warren L./Herbst, Derral R./Sohmer, S. H. (1999) (p. 270) var. radiata
State of Hawaii Hawaiian Islands	Kure Atoll	introduced	Starr, Forest/Martz, Kim/Loope, Lloyd (2001) (p. 8) var. radiata. Previously reported, not observed in this survey.
State of Hawaii Hawaiian Islands	Lāna‘i Island	introduced invasive	Oppenheimer, Hank (2007) (p. 20) Var. radiata. Voucher cited: Oppenheimer H100625 (BISH, PTBG)
State of Hawaii Hawaiian Islands	Maui Island	introduced invasive	Wagner, Warren L./Herbst, Derral R./Sohmer, S. H. (1999) (p. 270) var. radiata
State of Hawaii Hawaiian Islands	Moloka‘i Island	introduced invasive	Hughes, Guy D'Oyly (1995) (p. 2) Voucher cited: Hughes 42 (BISH) Sparingly naturalized to at least 410 m elevation in plantations and on disturbed, dry ridges in lowland areas.
State of Hawaii Hawaiian Islands	O‘ahu Island	introduced invasive	Wagner, Warren L./Herbst, Derral R./Sohmer, S. H. (1999) (p. 270) var. radiata
Japan (offshore islands) Bonin (Ogasawara) Islands	Bonin (Ogasawara) Islands	introduced	Kato, Hidetoshi (2007) As Bidens pilosa L. var. radiata Sch.Bip.
Marshall Islands Ralik Chain	Enewetak (Ãnewetak, Eniwetok) Atoll	introduced invasive	Whistler, W. A./Steele, O. (1999) (p. 33)
Marshall Islands Ralik Chain	Kwajalein (Kuwajleen) Atoll	introduced invasive	Whistler, W. A./Steele, O. (1999) (p. 33) Vouchers cited: Fosberg 3639; Herbst 8891, Herbst 8917, Herbst 8948, Herbst 8970, Herbst 8988, Herbst 8991; Whistler 11270
Marshall Islands Ralik Chain	Kwajalein (Kuwajleen) Atoll	introduced invasive	Fosberg, F. R. (1959) (p. 7) Voucher cited: Fosberg 36639 (US)
Marshall Islands Ralik Chain	Kwajalein (Kuwajleen) Atoll		National Tropical Botanical Garden (U.S.A. Hawaii. Kalaheo.) (1998) (voucher ID: PTBG 47463) Taxon name on voucher: Bidens alba
Marshall Islands Ratak Chain	Arno Atoll	introduced invasive	Vander Velde, Nancy/Vander Velde, Brian (2007) (p. 5) "Abundant; in lawns and ruderal areas; this was the principle invasive weed that residents complained about as being problematic and obnoxious".
Marshall Islands Ratak Chain	Majuro (Mãjro) Atoll	introduced invasive	Vander Velde, Nancy (2003) (p. 69)
Marshall Islands Ratak Chain	Maloelap Atoll		Imada, Clyde (2006)
Marshall Islands Ratak Chain	Mili (Mile) Atoll	introduced invasive	Vander Velde, Nancy/Vander Velde, Brian (2010) (p. A10) Uncommon; patches in runway, other ruderal areas of Mili, some on Bar, Nallo, not observed on Tokewa; compared with other atolls, relatively few infestations, some residents are aware of the undesirable nature of this species and have made efforts to control.
Marshall Islands Ratak Chain	Wotje (Wõjjã) Atoll	introduced	Vander Velde, Nancy/Vander Velde, Brian (2009) (p. 2) Voucher cited: Vander Velde 0514200909
Nauru Nauru Island	Nauru Island	introduced invasive	Thaman, R. R./Fosberg, F. R./Manner, H. I./Hassall, D. C. (1994) (p. 98) Vouchers cited: Scully 142N (US), Thaman & Manner 76 (SUVA)
Palau Palau (main island group)	Angaur Island	introduced invasive	Space, James C./Waterhouse, Barbara/Miles, Joel E./Tiobech, Joseph/Rengulbai, Kashgar (2003) (p. 103)
Palau Palau (main island group)	Angaur Island	introduced invasive	Space, James C./Lorence, David H./LaRosa, Anne Marie (2009) (p. 62)
Palau Palau (main island group)	Angaur Island		Beleu National Museum (Republic of Palau. Koror.) (1978) (voucher ID: BNM 1144) Taxon name on voucher: Bidens alba (L.) DC.
Palau Palau (main island group)	Babeldaob Island	introduced	Fosberg, F. R./Sachet, Marie-Hélène/Oliver, Royce (1979) (p. 283)
Palau Palau (main island group)	Babeldaob Island	introduced invasive	Space, James C./Waterhouse, Barbara/Miles, Joel E./Tiobech, Joseph/Rengulbai, Kashgar (2003) (p. 100)
Palau Palau (main island group)	Babeldaob Island		Raulerson, L./Rinehart, A. F./Falanruw, M. C. (1996) (p. 25)
Palau Palau (main island group)	Babeldaob Island	introduced invasive	Space, James C./Lorence, David H./LaRosa, Anne Marie (2009) (p. 62)
Palau Palau (main island group)	Babeldaob Island		Beleu National Museum (Republic of Palau. Koror.) (2007) (voucher ID: BNM 4421) Taxon name on voucher: Bidens alba (L.) DC
Palau Palau (main island group)	Babeldaob Island		National Tropical Botanical Garden (U.S.A. Hawaii. Kalaheo.) (2007) (voucher ID: PTBG 48158) Taxon name on voucher: Bidens alba
Palau Palau (main island group)	Kayangel (Ngcheangel) Island	introduced invasive	Space, James C./Waterhouse, Barbara/Miles, Joel E./Tiobech, Joseph/Rengulbai, Kashgar (2003) (p. 105)
Palau Palau (main island group)	Kayangel (Ngcheangel) Island	introduced invasive	Space, James C./Lorence, David H./LaRosa, Anne Marie (2009) (pp. 8, 62) Voucher: Lorence 9781 (PTBG, BNM, NY, TAMU, US)
Palau Palau (main island group)	Kayangel (Ngcheangel) Island		National Tropical Botanical Garden (U.S.A. Hawaii. Kalaheo.) (2008) (voucher ID: PTBG 74) Taxon name on voucher: Bidens alba (L.) DC.
Palau Palau (main island group)	Koror Island	introduced invasive	Space, James C./Waterhouse, Barbara/Miles, Joel E./Tiobech, Joseph/Rengulbai, Kashgar (2003) (p. 96)
Palau Palau (main island group)	Koror Island	introduced invasive	Space, James C./Lorence, David H./LaRosa, Anne Marie (2009) (p. 62)
Palau Palau (main island group)	Malakal Island	introduced invasive	Space, James C./Waterhouse, Barbara/Miles, Joel E./Tiobech, Joseph/Rengulbai, Kashgar (2003) (p. 96)
Palau Palau (main island group)	Malakal Island	introduced invasive	Space, James C./Lorence, David H./LaRosa, Anne Marie (2009) (p. 62)
Palau Palau (main island group)	Ngerkebesang Island	introduced invasive	Space, James C./Waterhouse, Barbara/Miles, Joel E./Tiobech, Joseph/Rengulbai, Kashgar (2003) (p. 96)
Palau Palau (main island group)	Ngerkebesang Island	introduced invasive	Space, James C./Lorence, David H./LaRosa, Anne Marie (2009) (p. 62)
Palau Palau (main island group)	Peleliu Island	introduced invasive	Space, James C./Waterhouse, Barbara/Miles, Joel E./Tiobech, Joseph/Rengulbai, Kashgar (2003) (p. 106)
Palau Palau (main island group)	Peleliu Island	introduced invasive	Space, James C./Lorence, David H./LaRosa, Anne Marie (2009) (p. 62)
Palau Rock Islands	Ngerchong Island	introduced invasive	Space, James C./Lorence, David H./LaRosa, Anne Marie (2009) (pp. 7, 62)
Palau Rock Islands	Ngeremdiu Island	eradicated invasive	Space, James C./Lorence, David H./LaRosa, Anne Marie (2009) (pp. 7, 62) Single specimen found, destroyed.
Palau Sonsorol Group	Merir Island	introduced invasive	Space, James C./Waterhouse, Barbara/Miles, Joel E./Tiobech, Joseph/Rengulbai, Kashgar (2003) (p. 109)
Palau Sonsorol Group	Sonsorol Island	introduced invasive	Space, James C./Waterhouse, Barbara/Miles, Joel E./Tiobech, Joseph/Rengulbai, Kashgar (2003) (p. 109)
United States (other Pacific offshore islands) Midway Atoll	Eastern Island	introduced invasive	Starr, Forest/Starr, Kim/Loope, Lloyd (2008) (pp. B-4) var. radiata
United States (other Pacific offshore islands) Midway Atoll	Midway Atoll	introduced invasive	Wagner, Warren L./Herbst, Derral R./Sohmer, S. H. (1999) (p. 270) var. radiata
United States (other Pacific offshore islands) Midway Atoll	Sand Island	introduced invasive	Starr, Forest/Starr, Kim/Loope, Lloyd (2008) (pp. B-4) var. radiata
United States (other Pacific offshore islands) Midway Atoll	Spit Island	introduced invasive	Starr, Forest/Starr, Kim/Loope, Lloyd (2008) (pp. B-4) var. radiata
United States (other Pacific offshore islands) Wake Islands	Wake Island	introduced invasive	Whistler, W. A./Steele, O. (1999) (p. 33)

Pacific Rim
Country/Terr./St. & Island group	Location	Cited status & Cited as invasive & Cited as cultivated & Cited as aboriginal introduction?	Reference & Comments
China China	Hong Kong	introduced invasive	Wu, Te-lin (2001) (p. 276) In wasteland.
Guatemala Guatemala	Guatemala (Republic of)	native	U.S. Dept. Agr., Agr. Res. Serv. (2011)
Honduras Honduras	Honduras (Republic of)	native	U.S. Dept. Agr., Agr. Res. Serv. (2011)
Mexico Mexico	Mexico (United Mexican States)	native	U.S. Dept. Agr., Agr. Res. Serv. (2011)
Perú Perú	Perú (Republic of)	native	U.S. Dept. Agr., Agr. Res. Serv. (2011)
Singapore Singapore	Singapore (Republic of)	introduced cultivated	Chong, Kwek Yan/Tan, Hugh T. W./Corlett, Richard T. (2009) (p. 18) Cultivated only

Indian Ocean
Country/Terr./St. & Island group	Location	Cited status & Cited as invasive & Cited as cultivated & Cited as aboriginal introduction?	Reference & Comments
British Indian Ocean Territory Chagos Archipelago	Diego Garcia Island	introduced invasive	Whistler, W. Arthur (1996) (p. 26)
British Indian Ocean Territory Chagos Archipelago	Diego Garcia Island		National Tropical Botanical Garden (U.S.A. Hawaii. Kalaheo.) (1995) (voucher ID: PTBG 37886) Taxon name on voucher: Bidens alba (L.) DC.

Control: 

Physical:  "Pulling is difficult, but hand weeding can be effective if done repeatedly for an extended period"  (Englberger, 2009; p. 13).

Chemical:  "Triclopyr (Garlon 4) can be used as a foliar spray"  (Englberger, 2009; p. 13).

Additional information:
Fact sheet from the University of Florida Extension Service. (PDF format)

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

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

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

References:

Beleu National Museum (Republic of Palau. Koror.). 1978. Voucher specimen #BNM1144(Canfield, J.E. 415).

Beleu National Museum (Republic of Palau. Koror.). 2007. Voucher specimen #BNM4421(Balick et al. 4421).

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.

Englberger, Konrad. 2009. Invasive weeds of Pohnpei: A guide for identification and public awareness. Conservation Society of Pohnpei. 29 pp.

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. Additional records of phanerogams from the northern Marshall Islands. Atoll Research Bulletin No. 68. Pacific Science Board, National Academy of Sciences, Washington. 9 pp.

Fosberg, F. R./Falanruw, M. V. C. 1980. Noteworthy Micronesian plants 4. Micronesica 16(2):201-210.

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

Herrera, Katherine/Lorence, David H./Flynn, Timothy/Balick, Michael J. 2010. Checklist of the vascular plants of Pohnpei with local names and uses. Allertonia, in press. National Tropical Botanical Garden, Lawai, Hawai‘i. 146 pp.

Hughes, Guy D'Oyly. 1995. New Hawaiian plant records II. In: Evenhuis, Neal L. and Miller, Scott, E., eds. Records of the Hawaii Biological Survey for 1994. Part 2: Notes. Bishop Museum Occasional Papers. 42:1-10.

Imada, Clyde. 2006. Flora of the Marshall Islands: Maloelap Atoll. Species determinations by Clyde Imada, Bishop Museum Herbarium, Hawai‘i. Unpublished checklist, 2 pp.

Josekutty, P. C./Wakuk, E. E./Joseph, M. J. 2002. Invasive/weedy angiosperms in Kosrae, Federated States of Micronesia. In: Invasive species and their management. Micronesica Suppl. 6:61-65.

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

Lorence, David H./Flynn, Timothy. 2010. Checklist of the plants of Kosrae. Unpublished checklist. National Tropical Botanical Garden, Lawai, Hawai‘i. 26 pp.

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

National Tropical Botanical Garden (U.S.A. Hawaii. Kalaheo.). 1995. Voucher specimen #PTBG37886(Art Whistler 9727).

National Tropical Botanical Garden (U.S.A. Hawaii. Kalaheo.). 1997. Voucher specimen #PTBG37720(M. J. Balick 3855).

National Tropical Botanical Garden (U.S.A. Hawaii. Kalaheo.). 2001. Voucher specimen #PTBG35337(David H. Lorence 8628).

National Tropical Botanical Garden (U.S.A. Hawaii. Kalaheo.). 2008. Voucher specimen #PTBG74(David H. Lorence 9781).

Oppenheimer, Hank. 2007. New plant records from Moloka‘i, Lāna‘i, Maui, and Hawai‘i for 2006. In: Evenhuis, Neal L. and Eldredge, Lucias G., eds. Records of the Hawaii Biological Survey for 2006. Part 2: Notes. Bishop Museum Occasional Papers 96:17-34.

Ragone, Diane/Lorence, David H. 2003. Botanical and ethnobotanical inventories of the National Park of American Samoa. National Tropical Botanical Garden, Kalaheo, Hawaii and Pacific Cooperative Studies Unit, Department of Botany, University of Hawaii. 91 pp.

Raulerson, L. 2006. Checklist of Plants of the Mariana Islands. University of Guam Herbarium Contribution 37:1-69. .

Raulerson, L./Rinehart, A. F./Falanruw, M. C. 1996. A botanical reconnaissance of the proposed Compact-impact road alignment on Babeldaob Island, Republic of Palau. U. of Guam Herbarium Cont. No. 32. 78 pp.

Space, James C./Lorence, David H./LaRosa, Anne Marie. 2009. Report to the Republic of Palau: 2008 update on Invasive Plant Species. USDA Forest Service, Hilo, Hawai‘i. 227 pp.

Space, James C./Waterhouse, Barbara/Miles, Joel E./Tiobech, Joseph/Rengulbai, Kashgar. 2003. Report to the Republic of Palau on invasive plant species of environmental concern. USDA Forest Service, Honolulu. 174 pp.

Starr, Forest/Martz, Kim/Loope, Lloyd. 2001. Botanical inventory of Kure Atoll. United States Geological Survey, Biological Resources Division, Haleakala Field Station, Hawai‘i. 22 pp.

Starr, Forest/Starr, Kim/Loope, Lloyd. 2008. Botanical survey of Midway Atoll. Prepared for: United States Fish and Wildlife Service. 27 pp. plus appendices.

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

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. 2011. Integrated Taxonomic Information System (ITIS) (on-line resource).

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

Vander Velde, Nancy. 0. Nancy Vander Velde, pers. com.

Vander Velde, Nancy. 2003. The vascular plants of Majuro Atoll, Republic of the Marshall Islands. Smithsonian Institution, Atoll Research Bulletin No. 503:1-141.

Vander Velde, Nancy/Vander Velde, Brian. 2007. Arno plants [preliminary working listing of plant species]. Unpublished checklist, 13 pp.

Vander Velde, Nancy/Vander Velde, Brian. 2009. Specimens from Likiep, Majuro, Wotje and Arno (unpublished checklist). 4 pp.

Vander Velde, Nancy/Vander Velde, Brian. 2010. Survey of Invasive Plant Species and Other Plants of Mili Atoll, Marshall Islands. USDA Forest Resource Management Grant Program. Unpublished report. 6 pp, plus tabulation of plants of Mili Atoll, 23 pp.

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).

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.

Whistler, W. Arthur. 1996. Botanical survey of Diego Garcia, Chagos Archipelago, British Indian Ocean Territory. Isle Botanica. 49 pp.

Wu, Te-lin. 2001. Check List of Hong Kong Plants. Hong Kong Herbarium and the South China Institute of Botany. Agriculture, Fisheries and Conservation Department Bulletin 1 (revised). 384 pp.