Flora of New Zealand Series

fireweed

Erect, annual or short-lived perennial herb, up to c. 1.5 m tall. Stems glabrous, branched above to form infl. Lower and mid cauline lvs glabrous, apetiolate, not lobed and remotely dentate to shallowly 1-pinnatisect, linear to lanceolate, acute, cuneate and often amplexicaul and deeply 1-3-fid at base, (4)-6-15-(20) × 0.3-2-(3.5) cm; venation pinnate. Uppermost cauline lvs smaller, entire or remotely dentate, often not amplexicaul. Capitula in loose panicles. Supplementary bracts 4-6, lanceolate, 1-2 mm long. Involucral bracts 8-12, linear, glabrous, 4.5-5.5 mm long. Ray florets 0. Disc yellow, 1-2 mm diam. Achenes subcylindric, only slightly narrowed to and constricted below apex, with 2-(3) rows of hairs in narrow grooves between broad ribs, 1.5-2.8 mm long; pappus 4-6 mm long.

N.: Northland to vicinity of Auckland City, Coromandel.

E. Australia 1975

Mostly waste places and coastal sites, also swamps, pasture and cultivated ground.

FL Nov-Apr.

S. diaschides was described and illustrated from naturalised N.Z. material by Drury (op. cit.) to account for material not catered for in Belcher's 1956 monograph. This entity was later described as S. cahillii Belcher from Australian material [ Muelleria 5 : 120 (1983)]. The lvs are similar to those of S. quadridentatus but are glabrous and more obviously toothed (Fig. 30).