Flora of New Zealand Series

Brazilian fireweed

Erect annual herb, 0.5- c. 1 m tall. Stems sparsely hairy to almost glabrous, branched above. Lvs sparsely hispidulous, usually lanate when very young; lower lvs petiolate, irregularly serrate to lyrate-pinnatifid or pinnatifid; mid cauline lvs petiolate or narrowed to long-cuneate base, not amplexicaul, ovate to elliptic, usually pinnatifid, sometimes lyrate-pinnatifid, 7-25 × 3-15 cm, with segments elliptic or oblong and irregularly serrate; uppermost lvs smaller, broader-based, and usually ± apetiolate with fewer, often narrower segments. Capitula in dense or open panicles. Supplementary bracts 7-14, linear, 1.5-5 mm long. Involucral bracts 12-14, linear, (6)-9-12 mm long. Disc mauve, 3-6-(7) mm diam. Achenes narrow-cylindric, narrowed to apex, 3-3.8 mm long, with scattered hairs between ribs; pappus pink to mauve, c. 10 mm long.

N.: vicinity of Auckland northwards.

Mexico to Argentina 1916

Scrubland, grassland, waste places, forest margins, gardens.

FL Jan-Dec.

Brazilian fireweed is easily distinguished by the brightly coloured, discoid capitula. It is locally common in Northland and has established on Great Barrier Id; it is an aggressive weed through much of the Pacific.