Pluchea indica (L.) Less., Asteraceae

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Present on Pacific Islands?  yes

Primarily a threat at high elevations?  no

Risk assessment results:  High risk, score: 11 (Go to the risk assessment).

Common name(s): [more details]

English: Indian camphorweed, Indian fleabane, Indian pluchea

Habit:  shrub

Description:  "Erect shrub, glabrous (or nearly so) throughout; leaves bright pale green, obovate or subelliptic, 3-4 (rarely 5) cm long, 1.5-2 (rarely 2.3) cm wide, nearly sessile, margins dentate, base cuneate, apex " obtuse; inflorescence compact, compound, terminal and subterminal, somewhat corymbose in appearance; heads of relatively few flowers; involucral bracts subdeltoid, in 3-4 series; heads c. 5 mm long, 2 mm broad; perfect flowers 1-3; corolla rose-purple, the 5-lobes evident, deltoid; pappus bristles mostly 18-20 per achene; mature achenes reddish-brown" (Stone, 1970; p. 589).

"Erect shrub to 2 m tall, sulcate-striate, much branched, branches finely shortly crisp-hairy, later becoming glabrate. Leaves thickly chartaceous, obovate, 2.3-8 cm long, 1-4 cm wide, minutely puberulent above, loosely puberulent to subglabrous with distinct veinlets beneath, apex acute to mucronate, margins acutely dentate, base attenuate, sessile or very shortly petiolate. Capitula narrowly cylindric to campanulate, ca. 5-6 mm (when fresh) or 9-10 mm (in dried specimens) in diam., 6-7 mm long, peduncle sessile to 10 mm long, forming dense terminal and axillary corymbs. Involucres ovate, 4-6 mm long, bracts 6-7 seriate; the outer obtuse, 2-2.5 mm long, 1.5 mm wide, ciliolate on margins; the inner lanceolate to linear, obtuse, 4-6 mm long, 0.25-1 mm wide, entire. Receptacle densely hirsutulous. Outer florets numerous, corolla 3-5 mm long; style far exerted; pappus white, 5 mm long, slightly exceeding corolla; achenes brown, cylindric with 5-7 pale ribs, slightly curved, 1 mm long, 0.3 mm wide, subglabrous. Central florets 2-7, corolla 4.5-5.5 mm long, 5-lobed at tip, lobes glandular; anthers and style far exserted; pappus white, as long as corolla; achenes vestigial as a small cartilaginous ring"  (Peng et al., 1998).

Habitat/ecology:  The problems associated with this species are similar to those associated with Pluchea carolinensis. This plant is confined to lowland habitats, particularly wetlands and fishponds (Smith, 1985; p. 199).  "Displaces forages in coastal pastures and natives in marshes and saline areas.  Destroys habitat of water birds"  (Motooka et al., 2003).

"Often in brackish marshes and other saline habitats. In Taiwan, widespread all along the western coastline, commonly occurring in littoral areas such as mangroves, brackish swamp, tidal flats, etc., occasionally found in forested land at low elevations" (Peng et al., 1998).

"Readily colonises disturbed saline areas and cliffs around tropical coasts, but has also been reported inland in Hawai‘i to a height of 450 m. The plant is not particularly competitive, and appears to be readily shaded out by taller shrubs and trees." (Swarbrick, 1997; p. 58). In New Caledonia, "cette espèce, localement abondante aux envirions de Koumac, a été récoltée seulement dans une région assez limitée du Nord" (MacKee, 1994; p. 37).

Propagation:  "Distribution is by wind-dispersed seeds, which probably have a short viability" (Swarbrick, 1997; p. 58).

Native range:  Native of India, south China, throughout Malaysia, south to Australia; possibly native in Guam, but weedy in appearance (Stone, 1970; p. 589).

Presence:

Pacific
Country/Terr./St. & Island group	Location	Cited status & Cited as invasive & Cited as cultivated & Cited as aboriginal introduction?	Reference & Comments
American Samoa American Samoa Islands	American Samoa Islands		Waterhouse, D. F. (1997) (p. 64)
American Samoa Manu‘a Islands	Ta‘u Island		National Tropical Botanical Garden (U.S.A. Hawaii. Kalaheo.) (1998) (voucher ID: PTBG 42704) Taxon name on voucher: Pluchea indica
American Samoa Manu‘a Islands	Ta‘u Island		National Tropical Botanical Garden (U.S.A. Hawaii. Kalaheo.) (1993) (voucher ID: PTBG 43376) Taxon name on voucher: Pluchea indica
Commonwealth of the Northern Mariana Islands (US) Northern Mariana Islands	Saipan Island	introduced	Fosberg, F. R./Sachet, Marie-Hélène/Oliver, Royce (1979) (p. 289)
Commonwealth of the Northern Mariana Islands (US) Northern Mariana Islands	Saipan Island		Bishop Museum (Honolulu) (1950) (voucher ID: BISH 132669) Taxon name on voucher: Pluchea indica (L.) Less.
Commonwealth of the Northern Mariana Islands (US) Northern Mariana Islands	Saipan Island		Bishop Museum (Honolulu) (1966) (voucher ID: BISH 401439) Taxon name on voucher: Pluchea indica (L.) Less.
Commonwealth of the Northern Mariana Islands (US) Northern Mariana Islands	Tinian Island	introduced	Raulerson, L. (2006) (p. 68)
Commonwealth of the Northern Mariana Islands (US) Northern Mariana Islands	Tinian Island		Bishop Museum (Honolulu) (1982) (voucher ID: BISH 593735) Taxon name on voucher: Pluchea indica (L.) Less.
Cook Islands Northern Cook Islands	Penrhyn (Tongareva) Island		McCormack, Gerald (2011)
Federated States of Micronesia Yap Islands	Ulithi Atoll	introduced	Fosberg, F. R./Sachet, Marie-Hélène/Oliver, Royce (1979) (p. 289)
Guam Guam Island	Guam Island	possibly native invasive	Stone, Benjamin C. (1970) (p. 589) Voucher cited: Stone 4033 (GUAM)
Guam Guam Island	Guam Island	introduced	Fosberg, F. R./Sachet, Marie-Hélène/Oliver, Royce (1979) (p. 289)
Guam Guam Island	Guam Island		Bishop Museum (Honolulu) (1963) (voucher ID: BISH 132670) Taxon name on voucher: Pluchea indica (L.) Less.
Guam Guam Island	Guam Island		Bishop Museum (Honolulu) (1966) (voucher ID: BISH 438123) Taxon name on voucher: Pluchea indica (L.) Less.
Guam Guam Island	Guam Island		Bishop Museum (Honolulu) (1966) (voucher ID: BISH 438124) Taxon name on voucher: Pluchea indica (L.) Less.
Guam Guam Island	Guam Island		Bishop Museum (Honolulu) (1966) (voucher ID: BISH 571336) Taxon name on voucher: Pluchea indica (L.) Less.
State of Hawaii Hawaiian Islands	French Frigate Shoals	introduced invasive	Wagner, Warren L./Herbst, Derral R./Sohmer, S. H. (1999) (p. 351)
State of Hawaii Hawaiian Islands	Hawai‘i (Big) Island	introduced invasive	Oppenheimer, Hank L./Bartlett, Randal T. (2002) (p. 4) Voucher cited: Oppenheimer H40023 (BISH)
State of Hawaii Hawaiian Islands	Kaho‘olawe Island	introduced invasive	Wagner, Warren L./Herbst, Derral R./Sohmer, S. H. (1999) (p. 351)
State of Hawaii Hawaiian Islands	Kaua‘i Island	introduced invasive	Wagner, Warren L./Herbst, Derral R./Sohmer, S. H. (1999) (p. 351)
State of Hawaii Hawaiian Islands	Kure Atoll	introduced invasive	Wagner, Warren L./Herbst, Derral R./Sohmer, S. H. (1999) (p. 351)
State of Hawaii Hawaiian Islands	Lāna‘i Island	introduced invasive	Wagner, Warren L./Herbst, Derral R./Sohmer, S. H. (1999) (p. 351)
State of Hawaii Hawaiian Islands	Laysan Island	introduced invasive	Wagner, Warren L./Herbst, Derral R./Sohmer, S. H. (1999) (p. 351)
State of Hawaii Hawaiian Islands	Laysan Island	introduced invasive	Starr, Forest/Martz, Kim (1999) (p. 10) Occasional on the far margins of the lagoon.
State of Hawaii Hawaiian Islands	Ni‘ihau, Lehua Islet	introduced invasive	Wood, K. R./LeGrande, Maya (2006) (p. 21) Vouchers cited: Lorence et al. 7129 (AD, PTBG, SING), K.R. Wood 11545 (BISH, PTBG, US)
State of Hawaii Hawaiian Islands	Maui Island	introduced invasive	Wagner, Warren L./Herbst, Derral R./Sohmer, S. H. (1999) (p. 351)
State of Hawaii Hawaiian Islands	Moloka‘i Island	introduced invasive	Wagner, Warren L./Herbst, Derral R./Sohmer, S. H. (1999) (p. 351)
State of Hawaii Hawaiian Islands	Ni‘ihau Island	introduced invasive	Wagner, Warren L./Herbst, Derral R./Sohmer, S. H. (1999) (p. 351)
State of Hawaii Hawaiian Islands	O‘ahu Island	introduced invasive	Wagner, Warren L./Herbst, Derral R./Sohmer, S. H. (1999) (p. 351)
Japan (offshore islands) Bonin (Ogasawara) Islands	Bonin (Ogasawara) Islands		Kato, Hidetoshi (2007)
Kiribati Banaba Island	Banaba (Ocean) Island	introduced	Fosberg, F. R./Sachet, Marie-Hélène/Oliver, Royce (1979) (p. 289)
Kiribati Line Islands	Kiritimati (Christmas) Atoll		Chock, Alvin K./Hamilton, Jr., Dean C. (1962) (p. 6) Voucher cited: Hamilton 8
Kiribati Line Islands	Kiritimati (Christmas) Atoll	introduced invasive	Wester, Lyndon (1985) (p. 33)
Kiribati Phoenix Islands	Kanton Island	introduced invasive	Fosberg, F. R./Stoddart, D. R. (1994) (p. 12) Voucher cited: Fosberg & Stoddart 24889 [54889?] (US, HAW, K)
Kiribati Tungaru (Gilbert) Islands	Butaritari Atoll	introduced	Fosberg, F. R./Sachet, Marie-Hélène/Oliver, Royce (1979) (p. 289)
Kiribati Tungaru (Gilbert) Islands	Butaritari Atoll	introduced invasive	Space, James C./Imada, Clyde T. (2004) (p. 10)
Kiribati Tungaru (Gilbert) Islands	Butaritari Atoll		National Tropical Botanical Garden (U.S.A. Hawaii. Kalaheo.) (1972) (voucher ID: PTBG 31159) Taxon name on voucher: Pluchea indica
Marshall Islands Ralik Chain	Enewetak (Ãnewetak, Eniwetok) Atoll	introduced	Fosberg, F. R./Sachet, Marie-Hélène/Oliver, Royce (1979) (p. 289)
Marshall Islands Ralik Chain	Enewetak (Ãnewetak, Eniwetok) Atoll		Bishop Museum (Honolulu) (1949) (voucher ID: BISH 132661) Taxon name on voucher: Pluchea indica (L.) Less.
Marshall Islands Ralik Chain	Enewetak (Ãnewetak, Eniwetok) Atoll		Bishop Museum (Honolulu) (1975) (voucher ID: BISH 404911) Taxon name on voucher: Pluchea indica (L.) Less.
Marshall Islands Ralik Chain	Enewetak (Ãnewetak, Eniwetok) Atoll		Bishop Museum (Honolulu) (1975) (voucher ID: BISH 583372) Taxon name on voucher: Pluchea indica (L.) Less.
Marshall Islands Ralik Chain	Enewetak (Ãnewetak, Eniwetok) Atoll		Bishop Museum (Honolulu) (1975) (voucher ID: BISH 583377) Taxon name on voucher: Pluchea indica (L.) Less.
Marshall Islands Ralik Chain	Kwajalein (Kuwajleen) Atoll	introduced	Fosberg, F. R./Sachet, Marie-Hélène/Oliver, Royce (1979) (p. 289)
Marshall Islands Ralik Chain	Kwajalein (Kuwajleen) Atoll	introduced invasive	Whistler, W. A./Steele, O. (1999) (pp. 36-37) Vouchers cited: Fosberg 26523, Fosberg 31179, Fosberg 31210, Whistler 11218. Also one without collector name or number.
Marshall Islands Ralik Chain	Kwajalein (Kuwajleen) Atoll	introduced invasive	Fosberg, F. R. (1955) (p. 21) Voucher cited: Fosberg 26523 (US)
Marshall Islands Ralik Chain	Kwajalein (Kuwajleen) Atoll		Bishop Museum (Honolulu) (1950) (voucher ID: BISH 132658) Taxon name on voucher: Pluchea indica (L.) Less.
Marshall Islands Ralik Chain	Kwajalein (Kuwajleen) Atoll		Bishop Museum (Honolulu) (1950) (voucher ID: BISH 132659) Taxon name on voucher: Pluchea indica (L.) Less.
Marshall Islands Ralik Chain	Kwajalein (Kuwajleen) Atoll		Bishop Museum (Honolulu) (1946) (voucher ID: BISH 132660) Taxon name on voucher: Pluchea indica (L.) Less.
Marshall Islands Ralik Chain	Kwajalein (Kuwajleen) Atoll		Bishop Museum (Honolulu) (1965) (voucher ID: BISH 452833) Taxon name on voucher: Pluchea indica (L.) Less.
Marshall Islands Ratak Chain	Majuro (Mãjro) Atoll	introduced	Fosberg, F. R./Sachet, Marie-Hélène/Oliver, Royce (1979) (p. 289)
Marshall Islands Ratak Chain	Majuro (Mãjro) Atoll	introduced invasive	Vander Velde, Nancy (2003) (p. 71)
Marshall Islands Ratak Chain	Majuro (Mãjro) Atoll		Bishop Museum (Honolulu) (year unknown) (voucher ID: BISH 17429) Taxon name on voucher: Pluchea indica (L.) Less.
Marshall Islands Ratak Chain	Majuro (Mãjro) Atoll		Bishop Museum (Honolulu) (1956) (voucher ID: BISH 17432) Taxon name on voucher: Pluchea indica (L.) Less.
Marshall Islands Ratak Chain	Majuro (Mãjro) Atoll		Bishop Museum (Honolulu) (1950) (voucher ID: BISH 132657) Taxon name on voucher: Pluchea indica (L.) Less.
New Caledonia New Caledonia Archipelago	Île Grande Terre	introduced invasive	MacKee, H. S. (1994) (p. 37) Vouchers cited: MacKee 16978, MacKee 33032, MacKee 33478, MacKee 34493
Palau Palau (main island group)	Angaur Island	introduced	Fosberg, F. R./Sachet, Marie-Hélène/Oliver, Royce (1979) (p. 289)
Palau Palau (main island group)	Angaur Island	introduced invasive	Space, James C./Waterhouse, Barbara/Miles, Joel E./Tiobech, Joseph/Rengulbai, Kashgar (2003) (pp. 14, 88)
Palau Palau (main island group)	Angaur Island	introduced invasive	Space, James C./Lorence, David H./LaRosa, Anne Marie (2009) (pp. 16-17)
Palau Palau (main island group)	Angaur Island		Bishop Museum (Honolulu) (1950) (voucher ID: BISH 132664) Taxon name on voucher: Pluchea indica (L.) Less.
Palau Palau (main island group)	Angaur Island		Bishop Museum (Honolulu) (1978) (voucher ID: BISH 432378) Taxon name on voucher: Pluchea indica (L.) Less.
Palau Palau (main island group)	Angaur Island		Beleu National Museum (Republic of Palau. Koror.) (1970) (voucher ID: BNM 259) Taxon name on voucher: Pluchea indica (L.) Less.
Palau Palau (main island group)	Angaur Island		National Tropical Botanical Garden (U.S.A. Hawaii. Kalaheo.) (1950) (voucher ID: PTBG 31158) Taxon name on voucher: Pluchea indica
Palau Palau (main island group)	Peleliu Island	introduced	Fosberg, F. R./Sachet, Marie-Hélène/Oliver, Royce (1979) (p. 289)
Palau Palau (main island group)	Peleliu Island	introduced invasive	Space, James C./Waterhouse, Barbara/Miles, Joel E./Tiobech, Joseph/Rengulbai, Kashgar (2003) (pp. 14, 90)
Palau Palau (main island group)	Peleliu Island		Bishop Museum (Honolulu) (1968) (voucher ID: BISH 81655) Taxon name on voucher: Pluchea indica (L.) Less.
Philippines Philippine Islands	Philippine Islands	native	U.S. Dept. Agr., Agr. Res. Serv. (2011)
Philippines Philippine Islands	Philippine Islands	native	Merrill, Elmer D. (1923) (p. 606) Along the seashore and tidal streams within the influence of salt or brackish water.
Samoa Western Samoa Islands	Western Samoa Islands		Waterhouse, D. F. (1997) (p. 64)
Tuvalu Tuvalu (Ellis) Islands	Tuvalu Islands		Swarbrick, John T. (1997) (p. 95)
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. 351)
United States (other Pacific offshore islands) Palmyra Atoll	Palmyra Atoll	introduced invasive	Wester, Lyndon (1985) (p. 33)

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	native	U.S. Dept. Agr., Agr. Res. Serv. (2011)
Australia Australia (continental)	Queensland	native	U.S. Dept. Agr., Agr. Res. Serv. (2011)
Cambodia Cambodia	Cambodia (Kingdom of)	native	U.S. Dept. Agr., Agr. Res. Serv. (2011)
China China	China (People's Republic of)	native	U.S. Dept. Agr., Agr. Res. Serv. (2011)
China China	Hong Kong	native	Wu, Te-lin (2001) (p. 286) On sandy beach.
Indonesia Indonesia	Indonesia (Republic of)	native	U.S. Dept. Agr., Agr. Res. Serv. (2011)
Japan Japan	Japan (country)	native	U.S. Dept. Agr., Agr. Res. Serv. (2011) Okinawa
Japan Japan	Japan (country)	introduced	Mito, Toshikazu/Uesugi, Tetsuro (2004) (p. 190)
Singapore Singapore	Singapore (Republic of)	native	U.S. Dept. Agr., Agr. Res. Serv. (2011)
Singapore Singapore	Singapore (Republic of)	native	Chong, Kwek Yan/Tan, Hugh T. W./Corlett, Richard T. (2009) (p. 71) Common
Taiwan Taiwan	Taiwan Island	native	U.S. Dept. Agr., Agr. Res. Serv. (2011)
Taiwan Taiwan	Taiwan Island	native	Peng, Ching-I/Chen, Chih-Huei/Leu, Wen-Pen/Yen, Hsin-Fu (1998) (pp. 287-297)
Taiwan Taiwan	Taiwan Island	native	Ching-I Peng, ed. (2011) "Widespread along the western coast, commonly in littoral areas such as mangrove and brackish swamps, tidal flats, occasionally in forests at low elevations".
Thailand Thailand	Thailand (Kingdom of)	native	U.S. Dept. Agr., Agr. Res. Serv. (2011)
Vietnam Vietnam	Vietnam (Socialist Republic of)	native	U.S. Dept. Agr., Agr. Res. Serv. (2011)

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) (pp. 58, 124)

Comments:  Widespread but not presently abundant on Guam.

"Readily hybridizes with Pluchea carolinensis to form an intermediate plant known as Pluchea x fosbergii Cooperr. & Galang where the two species occur together (Whistler & Steele, 1999; pp. 36-37).

Per Bill Sykes (pers. com.), "introduced accidentally to Motu Moananui [Penrhyn Island, Cook Islands] at the time that American engineers built the airstrip in the Second World War."

Control: 

Chemical: "Sensitive to 2,4-D and probably to all hormone-type dicot killers. HAVO staff reported control with glyphosate product at 1% in foliar applications (Zimmer, HAVO). Fern Duvall (DOFAW) cleared areas of fleabane in the Kanaha Pond Reserve with drizzle applications of 1 lb/acre of glyphosate (Rodeo®) to establish bird nesting sites"  (Motooka et al., 2003).

Additional information:
Excerpt from the book "Weeds of Hawaii‘s Pastures and Natural Areas; An Identification and Management Guide" (Motooka et al., 2003). (PDF format).
Photos and additional information at the University of Guam "Plants of Guam" web site.

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

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

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

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.

Beleu National Museum (Republic of Palau. Koror.). 1970. Voucher specimen #BNM259(Salsedo, Carl A. 358).

Bishop Museum (Honolulu). 0. Voucher specimen #BISH 17429 (collector unknown; collector's voucher number unknown).

Bishop Museum (Honolulu). 1946. Voucher specimen #BISH 132660 (Fosberg, F.R. 26523).

Bishop Museum (Honolulu). 1949. Voucher specimen #BISH 132661 (St.John, H. 23704).

Bishop Museum (Honolulu). 1950. Voucher specimen #BISH 132657 (Fosberg, F.R. 31196).

Bishop Museum (Honolulu). 1950. Voucher specimen #BISH 132658 (Fosberg, F.R. 31179).

Bishop Museum (Honolulu). 1950. Voucher specimen #BISH 132659 (Fosberg, F.R. 31210).

Bishop Museum (Honolulu). 1950. Voucher specimen #BISH 132664 (Fosberg, F.R. 31980).

Bishop Museum (Honolulu). 1950. Voucher specimen #BISH 132669 (Fosberg, F.R. 31279).

Bishop Museum (Honolulu). 1956. Voucher specimen #BISH 17432 (collector unknown 1122).

Bishop Museum (Honolulu). 1963. Voucher specimen #BISH 132670 (Fosberg, F.R. 43411).

Bishop Museum (Honolulu). 1965. Voucher specimen #BISH 452833 (unknown s.n.).

Bishop Museum (Honolulu). 1966. Voucher specimen #BISH 401439 (Evans, M. 2313).

Bishop Museum (Honolulu). 1966. Voucher specimen #BISH 438123 (Evans, M. 1443).

Bishop Museum (Honolulu). 1966. Voucher specimen #BISH 438124 (Evans, M. 1671).

Bishop Museum (Honolulu). 1966. Voucher specimen #BISH 571336 (Evans, M. 1671).

Bishop Museum (Honolulu). 1968. Voucher specimen #BISH 81655 (Emmons, B. 94).

Bishop Museum (Honolulu). 1975. Voucher specimen #BISH 404911 (Bryan Jr., E.H. 1668).

Bishop Museum (Honolulu). 1975. Voucher specimen #BISH 583372 (Bryan Jr., E.H. 1668).

Bishop Museum (Honolulu). 1975. Voucher specimen #BISH 583377 (Bryan Jr., E.H. 1682).

Bishop Museum (Honolulu). 1978. Voucher specimen #BISH 432378 (Stemmermann, R.L. 3386).

Bishop Museum (Honolulu). 1982. Voucher specimen #BISH 593735 (Herbst, D.R. 6813).

Ching-I Peng, ed. 2011. Digital flora of Taiwan (online resource).

Chock, Alvin K./Hamilton, Jr., Dean C. 1962. Plants of Christmas Island. Atoll Res. Bull. 90. Pacific Science Board, National Academy of Sciences, Washington. 7 pp.

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.

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

Fosberg, F. R./Stoddart, D. R. 1994. Flora of the Phoenix Islands, central Pacific. Smithsonian Institution, Washington. Atoll Research Bulletin 393. 60 pp.

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

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

McCormack, Gerald. 2011. Cook Islands Biodiversity Database, Version 2007.2. Cook Islands Natural Heritage Trust, Rarotonga.

Merrill, Elmer D. 1923. An enumeration of Philippine flowering plants, vol. 3 [reprint]. Bureau of Printing, Manila. 628 pp.

Mito, Toshikazu/Uesugi, Tetsuro. 2004. Invasive alien species in Japan: the status quo and the new regulation for prevention of their adverse effects. Global Environmental Research 8(2)/2004: 171-191.

Motooka, Philip/Castro, Luisa/Nelson, Duane/Nagai, Guy/Ching, Lincoln. 2003. Weeds of Hawaii‘s Pastures and Natural Areas; An Identification and Management Guide. College of Tropical Agriculture and Human Resources, University of Hawaii at Manoa. 184 pp.

Motooka, Philip/Ching, Lincoln/Nagai, Guy. 2002. Herbicidal Weed Control Methods for Pasture and Natural Areas of Hawaii. Cooperative Extension Service, College of Tropical Agriculture and Human Resources, University of Hawai‘i. CTAHR free publication WC-8.

Oppenheimer, Hank L./Bartlett, Randal T. 2002. New plant records from the main Hawaiian Islands. In: Evenhuis, Neal L. and Eldredge, Lucius G., eds. Records of the Hawaii Biological Survey for 2000. Part 2: Notes. Bishop Museum Occasional Papers. 69:1-14.

Peng, Ching-I/Chen, Chih-Huei/Leu, Wen-Pen/Yen, Hsin-Fu. 1998. Pluchea Cass. (Asteraceae: Inuleae) in Taiwan. Bot. Bull. Acad. Sin. (1998) 39: 287-297.

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

Smith, Clifford W. 1985. Impact of Alien Plants on Hawai‘i's Native Biota. In: Stone, Charles P. and Scott, J. Michael, eds. Hawai‘i's terrestrial ecosystems: preservation and Management. Cooperative National Park Resources Studies Unit, University of Hawaii, Manoa.

Space, James C./Imada, Clyde T. 2004. Report to the Republic of Kiribati on invasive plant species on the islands of Tarawa, Abemama, Butaritari and Maiana. Cont. no. 2003-006 to the Pac. Biol. Surv. USDA Forest Service and Bishop Museum, Honolulu. 103 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. 1999. S. S. Midway expedition, May 21, 1999 - June 16, 1999. Trip report prepared for: United States Fish and Wildlife Service. Unpublished. 22 pp. plus photos.

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

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