Derivation of name uncertain
Perennial herbs with corm-like rootstock, glabrous to hairy. Stems erect or ascending. Leaves basal and later along stems, alternate, margins entire, sessile or petiolate. Capitula diskoid, terminal, in spikes or racemes, with or without stalks. Involucral bracts in several rows, overlapping, unequal. Receptacle flat. Florets bisexual, tubular, purple, lavender or white. Achenes cylindrical, 10-ribbed, hairy. Pappus of feathery or barbed bristles.
Capitula in spikes or racemes, usually with purplish florets.
About 43 species from E North America.
Source: (2002). Dahlia. In: . Horticultural Flora of South-eastern Australia. Volume 4. Flowering plants. Dicotyledons. Part 3. The identification of garden and cultivated plants. University of New South Wales Press.