束尾草 shu wei cao

Rottboellia latifolia Steudel, Flora 29: 21. 1846; Phacel-urus angustifolius (Debeaux) Nakai; P. latifolius var. angusti-folius (Debeaux) Kitagawa; P. latifolius var. monostachys Keng ex S. L. Chen; Rottboellia latifolia var. angustifolia Debeaux.

Perennial, robust, with spreading, stout, scaly rhizomes. Culms tufted at nodes of rhizomes, erect, 1–2 m tall, 3–10 mm in diam., many-noded. Leaf sheaths smooth, glabrous, usually longer than internodes and overlapping; leaf blades linear-lanceolate, tough, 10–40 × 1.5–3 cm, glabrous or sparsely appressed-pilose, base rounded, margins scaberulous, apex attenuate; ligule rounded, 0.5–3 mm. Inflorescence of (1–)3–10 racemes, digitate or shortly racemose. Racemes up to 20 cm, stiffly suberect, often white-powdery; rachis internodes stoutly oblong-cuneate, sharply 3-angled, equaling or slightly shorter than pedicels. Sessile spikelet 8–10 mm, as long as internode; callus glabrous; lower glume linear-lanceolate, leathery, back concave, margins keeled, keels scabrid; upper glume spinulose on keel toward apex; lower floret staminate, palea present; upper lemma and palea subequal, styles connate, elongate, continued into a long feathery stigma 2-branched toward its apex. Pedicelled spikelet well developed, slightly laterally compressed, weakly curved; pedicel resembling internode. Fl. and fr. autumn.

Coastal salt marshes, river banks, irrigation channels on saline soils, forming colonies; below 1400 m. Anhui, Fujian, Hebei, Jiangsu, Liaoning, Shandong, Zhejiang [Japan, Korea].