PLAINS COREOPSIS, Coreopsis tinctoria Nutt. 1, plant showing growth habit; 2, seed. Annual, reproducing by seeds. Root system fibrous. Stems smooth with many slightly angled branches, up to 4 feet (1.2 m) tall. Leaves smooth, opposite or alternate, petioled; lower leaves divided into narrow, linear, or lance-shaped segments, upper leaves narrow and undivided. Flower heads numerous, slender-stalked, about 1 inch (2.5 cm) in diameter; ray flowers yellow or orange, with or without purplish-brown base, disk flowers dark purple or brown. Seed small, Iinear-oblong, incurved, wingless, black with a white scar. Found in fields and waste places, most abundant on low, moist, poorly drained soils.