Pluchea carolinensis (Jacq.) G.Don, Asteraceae

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Present on Pacific Islands?  yes

Primarily a threat at high elevations?  no

Risk assessment results:  High risk, score: 15 (Go to the risk assessment).

Other Latin names:  Conyza carolinensis Jacq.; Pluchea symphytifolia auct.

Common name(s): [more details]

English: cattletongue, cure-for-all, curry plant, pluchea, shrubby fleabane, sourbush, stinking fleabane, sweet scent, wild tobacco

I-Kiribati: te kaikare, te karei

Habit:  shrub

Description:  "Erect shrub, pubescent throughout; leaves dull gray-green, elliptic-lanceolate or narrowly elliptic-subovate, 8-16 x 3-6 cm, petiolate, entire, base acute or tapered, apex acute or subobtuse; inflorescence compound, terminal and subterminal, somewhat corymbose in appearance; heads of rather numerous flowers; involucral bracts broadly deltoid; heads slightly urceolate, about 7 x 5 mm; perfect flowers 12-17 per head; corollas pink or pinkish to white, the 5 lobes very small, tooth-like; pappus bristles mostly 10-12 per achene; mature achenes brownish-black" (Stone, 1970; p. 589).

"Erect shrub 1-2.5 m tall, much branched, branches densely tomentose. Leaves oblong-ovate to elliptic, 6-15 cm long, 2-6 cm wide, thinly tomentose and glandular on both surfaces, upper surface green, lower surface grayish, apex mucronulate-obtuse, margins entire or nearly so, base attenuate, petioles 1-2.5 cm long. Capitula 5-7 mm (when fresh) or ca. 10 mm (in dried specimens) in diameter, 6 mm long, peduncles 3-8 mm long, densely congested into terminal and axillary corymbs. Involucres ovate to campanulate, bracts greenish-purplish, 4-5-seriate; the outer very widely elliptic to very widely obovate, rounded at apex, 2-4 mm long, 1.5-2 mm wide, tomentose abaxially, ciliate at margins; the inner lanceolate to linear-lanceolate, acute at apex, 4-5 mm long, 0.5-1 mm wide, sparingly pubescent to glabrous. Receptacles flat, glabrous. Outer florets numerous, corolla filiform, pale greenish white, pinkish toward summit, 3.5-4 mm long, tip 3-lobed; pappus white, slightly shorter than corolla; mature achenes not available for examination. Central florets ca. 20-25; corolla whitish, pinkish toward summit, 4-5 mm long, sparingly glandular hairy at base; anthers obtuse at apex, shortly tailed at base; anthers and style exserted; achenes vestigial as a small, cartilaginous ring" (Peng et al., 1998).

Habitat/ecology:  "Cure-for-all is adapted to a wide variety of soils and sites. It tolerates excessively well- to poorly-drained soils, the full range of soil textures, acid and alkaline reactions, salt and salt spray, and compaction. A minimum of about 1000 mm of mean annual precipitation is required in upland sites, but it grows in much drier climates along streams and near mangroves and marshes. Cure-for-all may be found from near sea level to 1,000 m in elevation in Hawaii (University of Hawaii Botany 2002). The species is intolerant and cannot endure overhead shade or severe competition from brush or grass. It is common in disturbed areas such as construction sites, riverbanks, the margins of hammocks, road cuts and fill, vacant lots, eroded sites, landslides, burned areas, and abandoned fields. In Hawaii, cure-for-all quickly invades burned areas, but being early successional, is soon replaced by other species (Smith and Tunison 1992). Plants sprout after fires if they are not too intense (University of Hawaii Botany 2002)"  (Wildland shrubs of the United States and its territories).

This 1-2 m tall, fast-growing shrub forms thickets in dry habitats. It is found in Hawai‘i from sea level to 1,000 m elevation. "Common in pastures, forests, roadsides and vacant lots in dryer environments to wet areas.  Displaces forages in pastures and natives in natural areas"  (Motooka et al., 2003).  In New Caledonia, "parfois abondant mais reste localisé et semble être limité au Sud" (MacKee, 1994; p. 37).

"In Taiwan, P. carolinensis is naturalized in disturbed ruderal places of the countryside, often seen on barren mudstone slopes or associated with scrubby vegetation along roads. It occurs at ca. 50-200 m alt. Since the first discovery of this adventive species in Taiwan in 1987, its range has extended considerably on the island "  (Peng et al., 1998).

Propagation:  "The seeds are wind-dispersed and probably require wet, bare soil to germinate and establish themselves"  (Wildland shrubs of the United States and its territories).

Native range:  A tropical American species, native from Mexico through Central America to northern South America and in the West Indies Islands, now widespread as a rather aggressive weed in many Pacific islands (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
Commonwealth of the Northern Mariana Islands (US) Northern Mariana Islands	Tinian Island	introduced	Fosberg, F. R./Sachet, Marie-Hélène/Oliver, Royce (1979) (p. 289) As Pluchea symphytifolia
Commonwealth of the Northern Mariana Islands (US) Northern Mariana Islands	Tinian Island		Bishop Museum (Honolulu) (1980) (voucher ID: BISH 588197) Taxon name on voucher: Pluchea symphytifolia (Mill.) Gillis
Commonwealth of the Northern Mariana Islands (US) Northern Mariana Islands	Tinian Island		Bishop Museum (Honolulu) (1982) (voucher ID: BISH 594847) Taxon name on voucher: Pluchea symphytifolia (Mill.) Gillis
Commonwealth of the Northern Mariana Islands (US) Saipan	Saipan Island	introduced	Fosberg, F. R./Sachet, Marie-Hélène/Oliver, Royce (1979) (p. 289) As Pluchea symphytifolia
Commonwealth of the Northern Mariana Islands (US) Saipan	Saipan Island		Bishop Museum (Honolulu) (1950) (voucher ID: BISH 132666) Taxon name on voucher: Pluchea odorata (L.) Cass.
Commonwealth of the Northern Mariana Islands (US) Saipan	Saipan Island		National Tropical Botanical Garden (U.S.A. Hawaii. Kalaheo.) (1950) (voucher ID: PTBG 31160) Taxon name on voucher: Pluchea carolinensis
Cook Islands Northern Cook Islands	Penrhyn (Tongareva) Island		McCormack, Gerald (2013)
French Polynesia Society Islands	Bora Bora Island	introduced invasive	Florence, J./Chevillotte, H./Ollier, C./Meyer, J.-Y. (2013) "Très envahissant dans les champs abandonnés et bords de piste, gagnant sur la végétation indigène. Semble actuellement confiné à ce seul motu". Voucher cited: J. Florence 12054 (PAP) Adventice, menace pour la biodiversité.
French Polynesia Society Islands	Bora Bora Island		Bishop Museum (Honolulu) (1993) (voucher ID: BISH 663567) Taxon name on voucher: Pluchea symphytifolia (Mill.) Gillis
French Polynesia Society Islands	Maupiti (Maurua) Island	introduced invasive	Fosberg, F. R./Sachet, M.-H. (1987) (p. 69) Voucher cited: Fosberg 64754 (US)
French Polynesia Society Islands	Maupiti (Maurua) Island	introduced invasive	Florence, J./Chevillotte, H./Ollier, C./Meyer, J.-Y. (2013) Voucher cited: F.R. Fosberg 64754 (PAP) Adventice, menace pour la biodiversité.
French Polynesia Society Islands	Maupiti (Maurua) Island		Bishop Museum (Honolulu) (1985) (voucher ID: BISH 599719) Taxon name on voucher: Pluchea symphytifolia (Mill.) Gillis
Guam Guam Island	Guam Island	introduced invasive	Stone, Benjamin C. (1970) (p. 589) As Pluchea odorata (L.) Cass
Guam Guam Island	Guam Island	introduced	Fosberg, F. R./Sachet, Marie-Hélène/Oliver, Royce (1979) (p. 289) As Pluchea symphytifolia
Guam Guam Island	Guam Island		Bishop Museum (Honolulu) (1966) (voucher ID: BISH 438130) Taxon name on voucher: Pluchea symphytifolia (Mill.) Gillis
State of Hawaii Hawaiian Islands	French Frigate Shoals	introduced invasive	Wagner, Warren L./Herbst, Derral R./Sohmer, S. H. (1999) (pp. 351, 1863)
State of Hawaii Hawaiian Islands	Hawai‘i (Big) Island	introduced invasive	Wagner, Warren L./Herbst, Derral R./Sohmer, S. H. (1999) (pp. 351, 1863)
State of Hawaii Hawaiian Islands	Kaho‘olawe Island	introduced invasive	Wagner, Warren L./Herbst, Derral R./Sohmer, S. H. (1999) (pp. 351, 1863)
State of Hawaii Hawaiian Islands	Kaua‘i Island	introduced invasive	Wagner, Warren L./Herbst, Derral R./Sohmer, S. H. (1999) (pp. 351, 1863)
State of Hawaii Hawaiian Islands	Kure Atoll	introduced invasive	Wagner, Warren L./Herbst, Derral R./Sohmer, S. H. (1999) (pp. 351, 1863)
State of Hawaii Hawaiian Islands	Kure Atoll	introduced	Starr, Forest/Martz, Kim/Loope, Lloyd (2001) (p. 15) Previously reported, not observed in this survey.
State of Hawaii Hawaiian Islands	Lāna‘i Island	introduced invasive	Wagner, Warren L./Herbst, Derral R./Sohmer, S. H. (1999) (pp. 351, 1863)
State of Hawaii Hawaiian Islands	Laysan Island	introduced invasive	Wagner, Warren L./Herbst, Derral R./Sohmer, S. H. (1999) (pp. 351, 1863)
State of Hawaii Hawaiian Islands	Ni‘ihau, Lehua Islet	introduced invasive	Wood, K. R./LeGrande, Maya (2006) (p. 20) Vouchers cited: Flynn et al. 4858 (BISH, PTBG), K.R. Wood 11546 (BISH, PTBG, US)
State of Hawaii Hawaiian Islands	Maui Island	introduced invasive	Wagner, Warren L./Herbst, Derral R./Sohmer, S. H. (1999) (pp. 351, 1863)
State of Hawaii Hawaiian Islands	Moloka‘i Island	introduced invasive	Wagner, Warren L./Herbst, Derral R./Sohmer, S. H. (1999) (pp. 351, 1863)
State of Hawaii Hawaiian Islands	Ni‘ihau Island	introduced invasive	Wagner, Warren L./Herbst, Derral R./Sohmer, S. H. (1999) (pp. 351, 1863)
State of Hawaii Hawaiian Islands	O‘ahu Island	introduced invasive	Wagner, Warren L./Herbst, Derral R./Sohmer, S. H. (1999) (pp. 351, 1863)
Kiribati Line Islands	Kiritimati (Christmas) Atoll		Chock, Alvin K./Hamilton, Jr., Dean C. (1962) (p. 6) Vouchers cited: RAF Nat. Hist. Soc. (Gallagher) J, Hamilton 4 (BISH)
Kiribati Line Islands	Kiritimati (Christmas) Atoll	introduced invasive	Wester, Lyndon (1985) (p. 33)
Kiribati Line Islands	Tabuaeran (Fanning) Atoll	introduced invasive	Wester, Lyndon (1985) (p. 33)
Kiribati Phoenix Islands	Kanton Island	introduced invasive	Fosberg, F. R./Stoddart, D. R. (1994) (p. 12) Vouchers cited: MacDaniels [1950] (BISH), Fosberg & Stoddart 54888 (US, HAW, K), Fosberg & Walker 30210 (US), Degener & Hatheway 21295 (BISH, US, NY, A), Luomala 27 (BISH)
Kiribati Phoenix Islands	Kanton Island	introduced	Luomala, Katharine (1951) (p. 174) Voucher cited: Luomala 27
Kiribati Tungaru (Gilbert) Islands	Butaritari Atoll	introduced	Fosberg, F. R./Sachet, Marie-Hélène/Oliver, Royce (1979) (p. 289) As Pluchea symphytifolia
Kiribati Tungaru (Gilbert) Islands	Butaritari Atoll	introduced invasive	Space, James C./Imada, Clyde T. (2004) (p. 10) Voucher: Imada 2003-64 (BISH 697679)
Kiribati Tungaru (Gilbert) Islands	Butaritari Atoll		Bishop Museum (Honolulu) (2003) (voucher ID: BISH 697679) Taxon name on voucher: Pluchea carolinensis (Jacq.) G.Don
Kiribati Tungaru (Gilbert) Islands	Tarawa Atoll	introduced	Fosberg, F. R./Sachet, Marie-Hélène/Oliver, Royce (1979) (p. 289) As Pluchea symphytifolia
Kiribati Tungaru (Gilbert) Islands	Tarawa Atoll	introduced invasive	Space, James C./Imada, Clyde T. (2004) (p. 10) Voucher: Imada 2003-15 (BISH 697630)
Kiribati Tungaru (Gilbert) Islands	Tarawa Atoll		Bishop Museum (Honolulu) (2003) (voucher ID: BISH 697630) Taxon name on voucher: Pluchea carolinensis (Jacq.) G.Don
Marshall Islands Ralik Chain	Bikini (Pikinni) Atoll	introduced invasive	Whistler, W. A./Steele, O. (1999) (p. 36)
Marshall Islands Ralik Chain	Bikini (Pikinni) Atoll	introduced	Fosberg, F. R. (1988) (p. 15)
Marshall Islands Ralik Chain	Bikini (Pikinni) Atoll		Bishop Museum (Honolulu) (1958) (voucher ID: BISH 583841) Taxon name on voucher: Pluchea odorata (L.) Cass.
Marshall Islands Ralik Chain	Bikini (Pikinni) Atoll		Bishop Museum (Honolulu) (1985) (voucher ID: BISH 649608) Taxon name on voucher: Pluchea odorata (L.) Cass.
Marshall Islands Ralik Chain	Enewetak (Ãnewetak, Eniwetok) Atoll	introduced	Fosberg, F. R./Sachet, Marie-Hélène/Oliver, Royce (1979) (p. 289) As Pluchea symphytifolia
Marshall Islands Ralik Chain	Enewetak (Ãnewetak, Eniwetok) Atoll	introduced invasive	St. John, Harold (1960) (p. 334) Voucher cited: St. John 23703
Marshall Islands Ralik Chain	Enewetak (Ãnewetak, Eniwetok) Atoll	introduced invasive	Fosberg, F. R. (1955) (p. 21) Voucher cited: Fosberg 24405 (US)
Marshall Islands Ralik Chain	Enewetak (Ãnewetak, Eniwetok) Atoll		Bishop Museum (Honolulu) (1949) (voucher ID: BISH 132653) Taxon name on voucher: Pluchea carolinensis (Jacq.) G.Don
Marshall Islands Ralik Chain	Enewetak (Ãnewetak, Eniwetok) Atoll		Bishop Museum (Honolulu) (1975) (voucher ID: BISH 404903) Taxon name on voucher: Pluchea odorata (L.) Cass.
Marshall Islands Ralik Chain	Enewetak (Ãnewetak, Eniwetok) Atoll		Bishop Museum (Honolulu) (1975) (voucher ID: BISH 583375) Taxon name on voucher: Pluchea carolinensis (Jacq.) G.Don
Marshall Islands Ralik Chain	Enewetak (Ãnewetak, Eniwetok) Atoll		Bishop Museum (Honolulu) (1975) (voucher ID: BISH 583376) Taxon name on voucher: Pluchea odorata (L.) Cass.
Marshall Islands Ralik Chain	Kwajalein (Kuwajleen) Atoll	introduced	Fosberg, F. R./Sachet, Marie-Hélène/Oliver, Royce (1979) (p. 289) As Pluchea symphytifolia. Reported present by Fosberg et al. (1979) but not seen by Whistler and Steele (1999) in their survey of the U.S.-leased islands.
Marshall Islands Ralik Chain	Kwajalein (Kuwajleen) Atoll	introduced invasive	Whistler, W. A./Steele, O. (1999) (p. 36) Vouchers cited: Fosberg 31170, Fosberg 31208, Fosberg 39492. Not found on this survey and my longer be present.
Marshall Islands Ralik Chain	Kwajalein (Kuwajleen) Atoll	introduced invasive	Fosberg, F. R. (1955) (p. 21) Vouchers cited: Fosberg 31170 (US), Fosberg 31208 (US)
Marshall Islands Ralik Chain	Kwajalein (Kuwajleen) Atoll		Bishop Museum (Honolulu) (1950) (voucher ID: BISH 132654) Taxon name on voucher: Pluchea carolinensis (Jacq.) G.Don
Marshall Islands Ralik Chain	Kwajalein (Kuwajleen) Atoll		Bishop Museum (Honolulu) (1950) (voucher ID: BISH 567769) Taxon name on voucher: Pluchea odorata (L.) Cass.
Marshall Islands Ralik Chain	Rongerik (Roñdik) Atoll	introduced invasive	Whistler, W. A./Steele, O. (1999) (p. 36)
Marshall Islands Ralik Chain	Rongerik (Roñdik) Atoll		Bishop Museum (Honolulu) (1988) (voucher ID: BISH 607636) Taxon name on voucher: Pluchea carolinensis (Jacq.) G.Don
Marshall Islands Ratak Chain	Majuro (Mãjro) Atoll	introduced	Fosberg, F. R./Sachet, Marie-Hélène/Oliver, Royce (1979) (p. 289) As Pluchea symphytifolia
Marshall Islands Ratak Chain	Majuro (Mãjro) Atoll	introduced	Vander Velde, Nancy (2003) (p. 71)
Nauru Nauru Island	Nauru Island	introduced invasive	Meyer, Jean-Yves (2000) (p. 99) Pluchea sp.
New Caledonia New Caledonia	New Caledonia Islands	introduced invasive	Gargominy, Oliver/Bouchet, Philipe/Pascal, Michel/Jaffre, Tanguy/Tourneu, Jean-Christophe (1996) (p. 379) Parfois abondante mais reste localisée et semble être limitée au Sud.
New Caledonia New Caledonia Archipelago	Île Grande Terre	introduced invasive	MacKee, H. S. (1994) (p. 37) Vouchers cited: MacKee 37329, MacKee 37662, MacKee 39313
New Caledonia New Caledonia Archipelago	Île Leprédour	introduced invasive	MacKee, H. S. (1994) (p. 37) Voucher cited: Veillon 6857
Palau Palau (Belau ) (main island group)	Peleliu (Beliliou) Island	introduced	Fosberg, F. R./Sachet, Marie-Hélène/Oliver, Royce (1979) (p. 289) As Pluchea symphytifolia
Palau Palau (Belau ) (main island group)	Peleliu (Beliliou) Island	introduced invasive	Space, James C./Waterhouse, Barbara/Miles, Joel E./Tiobech, Joseph/Rengulbai, Kashgar (2003) (pp. 14, 90)
Palau Palau (Belau ) (main island group)	Peleliu (Beliliou) Island		Bishop Museum (Honolulu) (1950) (voucher ID: BISH 132663) Taxon name on voucher: Pluchea carolinensis (Jacq.) G.Don
Palau Palau (Belau ) (main island group)	Peleliu (Beliliou) Island		Bishop Museum (Honolulu) (1965) (voucher ID: BISH 438085) Taxon name on voucher: Pluchea symphytifolia (Mill.) Gillis
Tonga Tongatapu Group	Tongatapu Island	introduced invasive cultivated	Space, James C./Flynn, Tim (2001) (p. 8) Voucher: Flynn 6898 (PTBG, US)
Tonga Tongatapu Group	Tongatapu Island		National Tropical Botanical Garden (U.S.A. Hawaii. Kalaheo.) (2001) (voucher ID: PTBG 242) Taxon name on voucher: Pluchea carolinensis
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) (pp. 351, 1863)
United States (other Pacific offshore islands) Midway Atoll	Sand Island	introduced invasive	Starr, Forest/Starr, Kim/Loope, Lloyd (2008) (pp. B-12)
United States (other Pacific offshore islands) Palmyra Atoll	Palmyra Atoll	introduced invasive	Wester, Lyndon (1985) (p. 33)
United States (other Pacific offshore islands) Wake Islands	Wake Island	introduced invasive	Fosberg, F. R. (1959) (p. 19) Voucher cited: Fosberg 33621
United States (other Pacific offshore islands) Wake Islands	Wake Island	introduced invasive	Fosberg, F. R./Sachet, M.-H. (1969) (p. 15)
United States (other Pacific offshore islands) Wake Islands	Wake Island	introduced invasive	Fosberg, F. R. (1955) (p. 21) Voucher cited: Fosberg 34447 (US)
Vanuatu New Hebrides Islands	Êfaté (Efete) Island	introduced invasive	Orapa, Warea (year unknown) Communication to Aliens listserver.
Vanuatu New Hebrides Islands	Êfaté (Efete) Island		Bishop Museum (Honolulu) (1978) (voucher ID: BISH 424760) Taxon name on voucher: Pluchea odorata (L.) Cass.
Vanuatu New Hebrides Islands	Espirito Santo Island	introduced invasive	Orapa, Warea (year unknown) Communication to Aliens listserver.
Wallis and Futuna Wallis and Futuna (Horne) Islands	Wallis (‘Uvea) Island	introduced invasive	Meyer, Jean-Yves (2007) (pp. 11, 32) Cet arbuste est localement naturalisé et n’a été observé que dans un seul site de l’île (la décharge de Valokia) où il a apparemment été introduit avec des camions et des bulldozers abandonnés. Cette espèce peut se révéler très envahissante en zone littorale sur substrat calcaire.

Pacific Rim
Country/Terr./St. & Island group	Location	Cited status & Cited as invasive & Cited as cultivated & Cited as aboriginal introduction?	Reference & Comments
Central America Central America (Pacific rim)	Costa Rica (Republic of)	native	U.S. Dept. Agr., Agr. Res. Serv. (2013)
Central America Central America (Pacific rim)	El Salvador (Republic of)	native	U.S. Dept. Agr., Agr. Res. Serv. (2013)
Central America Central America (Pacific rim)	Guatemala (Republic of)	native	U.S. Dept. Agr., Agr. Res. Serv. (2013)
Central America Central America (Pacific rim)	Honduras (Republic of)	native	U.S. Dept. Agr., Agr. Res. Serv. (2013)
Central America Central America (Pacific rim)	Nicaragua (Republic of)	native	U.S. Dept. Agr., Agr. Res. Serv. (2013)
Central America Central America (Pacific rim)	Panama (Republic of)	native	U.S. Dept. Agr., Agr. Res. Serv. (2013)
Mexico Mexico	Mexico (United Mexican States)	native	U.S. Dept. Agr., Agr. Res. Serv. (2013)
South America (Pacific rim) South America (Pacific rim)	Colombia	native	Francis, John K., ed. (2009)
South America (Pacific rim) South America (Pacific rim)	Ecuador (Republic of) (continental)	native	Francis, John K., ed. (2009)
Taiwan Taiwan Island	Taiwan Island	introduced invasive	Peng, Ching-I/Chen, Chih-Huei/Leu, Wen-Pen/Yen, Hsin-Fu (1998) (pp. 287-297)
Taiwan Taiwan Island	Taiwan Island	introduced invasive	Ching-I Peng, ed. (2013) "Naturalized in disturbed ruderal places, often on barren mudstone slopes or associated with scrubby vegetation along roads, 50-200 m. Since its first discovery in Taiwan in 1987, the species has extended its range in lowlands of southern part of the island".

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 37885) Taxon name on voucher: Pluchea carolinensis (Jacq.) G. Don

Also reported from
Country/Terr./St. & Island group	Location	Cited status & Cited as invasive & Cited as cultivated & Cited as aboriginal introduction?	Reference & Comments
United States (continental except west coast) United States (other states)	United States (other states)	native	U.S. Dept. Agr., Agr. Res. Serv. (2013)
United States (continental except west coast) United States (other states)	USA (Florida)	native	Francis, John K., ed. (2009)

Comments:  This species (alone and together with Pluchea indica) seem to be highly correlated with military airfields constructed in the Pacific during World War II. 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." Not common there. Abundant near American military bases built on Santo and Efate Islands in Vanuatu. (Warea Orapa, communication to Aliens listserver).

"Readily hybridizes with Pluchea indica to form an intermediate plant known as Pluchea x fosbergii Cooperr. & Galang where the two species occur together (Whistler & Steele, 1999; pp. 36-37). Often found growing and hybridizing with P. indica (Stone, 1970; p. 589).

Widespread but not presently abundant on Guam.

Naturalizing on Tongatapu, Tonga but presently in a limited area as far as could be determined (along Alaivahamama road and between Taufa'ahau Road and the lagoon as far south as the Tongan National Centre) (Space & Flynn, 2001).

Control: 

Chemical: "Sensitive to 1 lb/acre 2,4-D, 0.5 lb/acre dicamba, and 0.25 lb/acre triclopyr. Readily controlled by 0.5 lb/acre triclopyr in drizzle applications. HAVO staff reported control with foliar application of glyphosate at 1% product (Chris Zimmer, HAVO)"  (Motooka et al., 2003).

Biological: Some biological control agents have been introduced in Hawai‘i but they have not been effective (Julien, 1992; p. 30).  "A seed insect, Acinia picturata (Diptera: Tephritidae), was introduced in Hawaii andalthough now well established, has had no significant effect on the shrub (Alyokhin and others 2001)"  (Wildland shrubs of the United States and its territories).