2. Eupatorium cannabinum Linnaeus, Sp. Pl. 2: 838. 1753.
大麻叶泽兰 da ma ye ze lan
Eupatorium nodiflorum Wallich ex Candolle.
Herbs, perennial, 50-150 cm tall. Rhizomes robust, with many fibrous roots. Stems erect, purplish red, simple or only apically corymbose branched, puberulent; synflorescence branches and peduncles more densely hairy, glabrescent in median lower part by anthesis. Leaves opposite, shortly petiolate; petiole ca. 5 mm; median and lower leaves irregularly lobed; central lobe elliptic or narrowly lanceolate, large, 6-11 × 2-3 cm, base cuneate or broadly cuneate, apex acuminate or long acuminate; lateral lobes same shape as central lobe, smaller; upper stem leaves gradually smaller, irregularly lobed or simple; lower stem leaves shed by anthesis; all stem leaves scabrid, rather thick, sparsely puberulent and glandular, more densely hairy abaxially and on veins, pinnately veined, lateral veins 5- or 6-paired, margin serrate, undulate. Synflorescences terminal, of densely compound corymbs. Capitula numerous, 3-7-flowered; involucre campanulate, ca. 6 mm; phyllaries 2- or 3-seriate, imbricate; outer phyllaries short, ovate-lanceolate, ca. 2 mm, puberulent; median and inner phyllaries gradually longer, with membranous margin and purplish tip; corollas purple-red, pink, or whitish, ca. 5 mm, outside sparsely yellow glandular. Achenes black-brown, cylindric, ca. 3 mm, 5-ribbed, with yellow glands; pappus setae white, ca. 5 mm. 2n = 20.
Summits of small hills, grasslands, among bamboos. Jiangsu, ?Taiwan, Zhejiang, may be introduced and naturalized [Europe].