Berkheya johnstoniana Britten

Compositae, G. V. Pope. Flora Zambesiaca 6:1. 1992

Morphology General Habit

A perennial herb up to c. 80 cm. tall, from a stout creeping woody roostock.

Morphology Stem

Stems annual single erect simple, thinly pilose-araneose, leafy with the leaves decurrent in discontinuous wings on the stem; wings usually not extending to the node below, absent from uppermost leaves, up to c. 5 mm. wide, coarsely dentate with indumentum as in leaves.

Morphology Leaves

Leaves crowded at the stem base, decreasing in size and density towards the stem apex, sessile; basal leaves ascending-subrosulate, 10–27 x 2–6 cm., narrowly oblong-oblanceolate in outline, apex acute, base ± long-tapering becoming petiole-like, somewhat stem clasping, margins pinnatilobed or pinnatifid with the lobes irregularly and often inconspicuously dentate, upper surface and margins beset with patent stramineous spine-like bristles 2–4 mm. long, the longest at tooth apices, lower surface white felted-tomentose; upper cauline leaves fewer, decreasing in size becoming linear and bract-like.

Morphology Reproductive morphology Inflorescences Capitulum

Capitula discoid, 3–7, laxly to densely clustered at the stem apex, 2–2.5 cm. in diam.

Morphology Reproductive morphology Inflorescences Bracts Phyllaries

Phyllaries mostly 8–15 x 1–2 mm., the outer and innermost somewhat shorter, linear-tapering or subulate, spine-tipped; the outer somewhat leaf-like with 1–4 mm. long spine-like bristles on the margins as in leaves, thinly pilose-araneose on the backs or glabrescent; the inner spinescent-ciliate to -barbellate or unarmed.

Morphology Reproductive morphology Flowers Receptacle

Receptacular alveolae margins with paleaceous setae to c. 6 mm. long.

Morphology Reproductive morphology Flowers Florets

Florets numerous; corollas yellow, 10–16 mm. long; achenes 2–3 mm. long, turbinate, obscurely 8–10-ribbed, hispid-strigose; pappus scales 20–40, 2–3-seriate, of subulate paleaceous barbellate setae 8–10 mm. long.