糙草 cao cao

Stem slender, to 90 cm tall, hollow, with 5 or 6 longitudinal ribs, glochidiate along ribs, usually branched. Lower stem leaves petiolate, spatulate or narrowly oblong, 5-8 × 0.8-1.5 cm, sparsely minutely hispid, margin entire or finely dentate; upper stem leaves sessile, becoming gradually smaller and subopposite. Pedicel short or absent. Calyx ca. 1.6 mm, parted to below middle, minutely hispid; lobes somewhat unequal, linear-lanceolate, to 8 mm wide after anthesis. Corolla blue, ca. 2.5 mm; tube longer than limb; throat appendages tuberclelike; lobes of limb somewhat unequal, broadly ovate to ovate. Anther ca. 0.6 mm. Style ca. 0.8 mm, included. Nutlets narrowly ovoid, ca. 3 mm; attachment scar orbicular. Fl. and fr. Jul-Sep. 2n = 48.

Hillside meadows, near villages, field margins; above 2000 m. Gansu, Nei Mongol, Qinghai, N Shaanxi, Shanxi, Sichuan, Xinjiang, NE Xizang [N India, Kashmir, Kazakhstan, Kyrgyzstan, Mongolia, Nepal, Russia, Tajikistan, Turkmenistan, Uzbekistan; N and NW Africa, SW and W Asia, Europe].