Present on Pacific Islands?  yes

Threat only at high elevations?  no

Habit:  herb

Description:  "Erect annual to 2 m tall, simple below and with main axis continuing nearly to tip, but more or less diffusely branched upward when well-developed; stem puberulent or woolly-puberulent, especially upward, often also somewhat viscid or glandular; basal leaves none; cauline leaves opposite, lower ones reduced and often soon deciduous, others well-developed, with slender petiole 1-8 cm long and a thin, deltoid-ovate to broadly subcordate blade mostly 2-8 cm long and wide, palmately tri-nerved, evidently crenate, often atomiferous-glandular, and otherwise sparsely hairy (especially along veins) or nearly glabrous; heads numerous to very numerous on slender peduncles mostly (2) 5-15 mm long; heads mostly 8-13-flowered, cylindric, the involucre 6-9 mm high, its slender bracts strongly imbricate in several series, greenish with hyaline margins, commonly with 2 pale principal veins flanking midline, often with thinner vein delimiting each of the hyaline margins; corollas greenish white, very slender, scarcely expanded upward, about 4 mm long; style branches filiform; achenes about 2 mm long, blackish, antrorsely strigose or more loosely hirsute-strigose"  (Wiggins & Porter, 1971; pp. 320-322).

Habitat/ecology:  "A common weed of much of tropical America" (Wiggins & Porter, 1971; pp. 320-322).

Propagation:  Seed

Native range:  Mexico, Central and South America (GRIN)

Presence:

Pacific
Country/Terr./St. & Island group	Location	Cited status & Cited as invasive & Cited as cultivated & Cited as aboriginal introduction?	Reference & Comments
Ecuador (Galápagos Islands) Darwin Islands	Darwin Island	probably introduced invasive	Charles Darwin Research Station (2005)
Ecuador (Galápagos Islands) Fernandina Group	Fernandina Island	probably introduced invasive	Charles Darwin Research Station (2005)
Ecuador (Galápagos Islands) Isabela Group	Isabela Island	probably introduced invasive	Charles Darwin Research Station (2005)
Ecuador (Galápagos Islands) Isabela Group	Volcan Cerro Azul	probably introduced invasive	Charles Darwin Research Station (2005)
Ecuador (Galápagos Islands) Isabela Group	Volcan Darwin	probably introduced invasive	Charles Darwin Research Station (2005)
Ecuador (Galápagos Islands) Isabela Group	Volcan Sierra Negra	probably introduced invasive	Charles Darwin Research Station (2005)
Ecuador (Galápagos Islands) Santa Cruz Group	Santa Cruz Island	probably introduced invasive	Charles Darwin Research Station (2005)
Ecuador (Galápagos Islands) Wolf Islands	Wolf Island	probably introduced invasive	Charles Darwin Research Station (2005)

Pacific Rim
Country/Terr./St. & Island group	Location	Cited status & Cited as invasive & Cited as cultivated & Cited as aboriginal introduction?	Reference & Comments
Colombia Colombia	Colombia (Republic of)	native	U.S. Dept. Agr., Agr. Res. Serv. (2007)
Costa Rica Costa Rica	Costa Rica (Republic of)	native	U.S. Dept. Agr., Agr. Res. Serv. (2007)
Ecuador (Mainland) Ecuador	Ecuador (Republic of) (continental)	native	U.S. Dept. Agr., Agr. Res. Serv. (2007)
El Salvador El Salvador	El Salvador (Republic of)	native	U.S. Dept. Agr., Agr. Res. Serv. (2007)
Guatemala Guatemala	Guatemala (Republic of)	native	U.S. Dept. Agr., Agr. Res. Serv. (2007)
Honduras Honduras	Honduras (Republic of)	native	U.S. Dept. Agr., Agr. Res. Serv. (2007)
Mexico Mexico	Mexico (United Mexican States)	native	U.S. Dept. Agr., Agr. Res. Serv. (2007)
Nicaragua Nicaragua	Nicaragua (Republic of)	native	U.S. Dept. Agr., Agr. Res. Serv. (2007)
Panama Panama	Panama (Republic of)	native	U.S. Dept. Agr., Agr. Res. Serv. (2007)
Perú Perú	Perú (Republic of)	native	U.S. Dept. Agr., Agr. Res. Serv. (2007)

Comments:  Probably not native to the Galápagos Islands, possibly introduced, per Charles Darwin Research Station.

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

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

References:

Charles Darwin Research Station. 2005. CDRS Herbarium records.

U.S. Dept. Agr., Agr. Res. Serv. 2007. National Genetic Resources Program. Germplasm Resources Information Network (GRIN). Online searchable database.

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