General: Annual herb from a taproot; stems erect, slender, simple or few-branched, hairless or glandular-hairy or obscurely white-woolly, 15-100 cm tall.
Leaves: Basal leaves pinnately cleft, the lowermost 1 to 2 times pinnately cleft with slender axis and narrow ultimate segments 1-15 mm long, 1-2 mm wide; stem leaves similar to the basal, alternate, reduced upwards, the axils and midribs generally white-hairy.
Flowers: Inflorescences dense, ball-like clusters of 50 to 100 stalkless flowers, the clusters on long bractless stalks terminating the stem and branches; corollas pale blue, 6-10 mm long, the tube flaring to five linear-oblong (1 mm wide) lobes about as long as the tube; calyces expanded in fruit, the five lobes pointy-tipped.
Fruits: Capsules, egg-shaped to spherical, with three 1- to 3-seeded chambers; seeds 1.5 mm long, becoming sticky when moistened.
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.
Dry, sandy, gravelly or rocky waste places in the lowland, steppe, and montane zones; rare in S BC, where probably introduced; WA and OR; S to N ID and CA; reported as introduced in AK and YT.