Coreopsis leavenworthii
Fl. N. Amer. 2: 346. 1842.
Annuals, (10–)30–70(–150+) cm. Leaves: proximal blades usually 1(–2)-pinnate, terminal lobes ± elliptic or oblanceolate to lanceolate or linear, 15–30+ × 4–8(–12+) mm; cauline blades simple or 1(–3)-pinnate, simple blades or terminal lobes narrowly oblanceolate to linear, 8–35(–70+) × 1–3(–5) mm. Peduncles 2–5(–8) cm. Calyculi of deltate-ovate to oblong or linear bractlets 2–6+ mm. Phyllaries ± lance-oblong to lanceolate, (4–)5–9 mm. Ray laminae usually yellow throughout, rarely with proximal red-brown blotch, 8–15+ mm. Disc corollas 2.2–3.5 mm. Cypselae 2–3 mm, wings 0.2–0.8+ mm wide; pappi of 2 subulate scales (0.2–)0.4–1(–1.4+) mm. 2n = 24 (+ 0–2 Bs).
Phenology: Flowering year round, mostly May–Jul.
Habitat: Moist, sandy soils, flatwoods, ditches
Elevation: 0–20+ m
Discussion
Plants here (and generally) treated as Coreopsis leavenworthii probably should be included within the circumscription adopted here for C. tinctoria.
Selected References
None.