Coronidium rupicola (DC.) Paul G.Wilson

Asteraceae

Wilson, Paul G. (2008) Nuytsia 18: 300.

Yellow Button; Everlasting

Usually flowers and fruits as a shrub up to 2 m tall but often flowers when smaller.

Leaf blades variable, about 3.5-19 x 0.5-2 cm, underside covered with matted white hairs which completely hide the venation. Petioles about 8-10 mm long. Young twigs clothed in hairs like those on the leaves.

Each flat-topped, button-shaped or cup-shaped flower head (1-2 cm diam.) contains numerous (more than 100?) flowers. Flowers surrounded by an involucre of woolly-hairy overlapping bracts. Calyx consists of a whorl of hairs (pappus). Anthers fused together but the filaments are free.

Fruits about 0.5 mm long, produced in heads which are subtended by numerous woolly-hairy overlapping bracts. Each fruit consists of a cylindrical nut with a plume of white hairs at one end. Each plume hair armed with numerous microscopic barbs. Embryo pale brown and oily, cotyledons about as wide as the radicle.

Cotyledons about 2-3 mm wide. At the tenth leaf stage: the underside of the leaf blades densely clothed in white, felty hairs. Stems and terminal buds similarly clothed. Leaf bases clasping the stem. Seed germination time 16 to 21 days.

Endemic to Australia, occurs in NEQ and CEQ. Altitudinal range in NEQ from near sea level to 1500 m. Grows in open forest, wet sclerophyll forest and disturbed rain forest on sandy soils, particularly those derived from granite.

Has potential in horticulture as a rockery plant.

Helichrysum rupicola DC. var. rupicola, Bibliotheca Botanica 89(4): 1225(1928). Helichrysum rupicola DC., Prodromus 6: 190(1838), Type: in Nova-Hollandia tropica ad rupes graminosas capitis Cleveland lat. 19 degrees S cl. Cunningham junis flor. Legit.