Crassocephalum crepidioides (Benth.) S.Moore

Moore, S. le M. (1912) The Journal of Botany : 211.

Thickhead

Usually flowers and fruits as a herb but also flowers as a shrub about 1 m tall or more. Twigs and stems very pithy.

Leaf blades rather variable in size and shape, 10-20 x 5-10 cm. Midrib usually purple on the upper surface. Petioles grooved on the upper surface. Stems and twigs longitudinally ribbed. Midrib and lateral veins clothed with hairs on both the upper and lower surfaces of the leaf blade.

Flowers borne in heads with more than 100 florets per head subtended by persistent bracts. Only disk florets produced. Corolla tube about 9 mm long, lobes about 1 mm long. Pollen white.

Pappus hairs armed with upward pointing spines. Nutlets about 2 mm long, longitudinally ribbed with brown glabrous and cream hairy sections. Cotyledons about as wide as the radicle.

Cotyledons about 6-9 x 6-9 mm, petiole about 5 mm long. First pair of leaves alternate, margins toothed. At the tenth leaf stage: leaves lanceolate, apex acute, base attenuate, margins serrate. Lateral veins depressed on the upper surface. Septate hairs present on both the upper and lower surfaces of the leaf blade. Seed germination time 10 days.

An introduced species originally from Africa and Madagascar, now naturalised in NEQ, CEQ and southwards as far as coastal central New South Wales. Altitudinal range in NEQ from 200-1000 m. Usually grows as a weed of agricultural land and waste places but also found along roads in rain forest.