General:
Annual herb from a taproot; stems erect, simple to freely branched, 0.3-2.0 m tall, grooved, often reddish, glabrous to short-hairy or sparsely hairy below the flowers.
Leaves:
Alternate or opposite, leaf blades 2.5-14 cm long, glabrous or nearly so, egg-shaped to deltoid-elliptic.
Flowers:
Inflorescence in terminal and axillary spikes; bracts linear-lanceolate and spiny; sepals unequal; stamens 3-4.
Fruits:
Capsules opening along an "equator", the top coming off like a lid, 1-seeded; seeds 1 mm long, lens-shaped.
If more than one illustration is available for a species (e.g., separate illustrations were provided for two subspecies) then links to the separate images will be provided below. Note that individual subspecies or varietal illustrations are not always available.
Illustration Source: The Illustrated Flora of British Columbia