Dichanthium caricosum (L.) A. Camus

Perennial, stoloniferous. Culms tufted at nodes of stolons, geniculately ascending, 30–60 cm tall, nodes glabrous or pubescent. Leaf sheaths compressed, keeled, shorter than internodes; leaf blades flat, 15–20 cm × 2.5–5 mm, glabrous or with a few hairs at base, margins smooth or scabrid, apex acuminate; ligule less than 1 mm, margin ciliate. Inflorescence terminal; peduncle glabrous; racemes (1–)2–4, 2.5–5 cm, with 1–3 pairs of homogamous spikelets. Sessile spikelet 3–3.5 mm; lower glume obovate-elliptic or obovate-oblong, papery, 8–12-veined, glabrous or often sparsely hirsute on lower back, slightly glossy, margins shortly ciliate, keels winged, apex rounded; upper glume ciliate above middle, apex obtuse; awn 1.5–2.5 cm, weakly geniculate. Caryopsis obovate-oblong. Pedicelled spikelet many-veined, resembling sessile. Fl. and fr. Oct–Mar. 2n = 20, 40.

Guizhou, Yunnan [India, Malaysia, Myanmar, Sri Lanka, Thailand; introduced elsewhere].

Hill slopes, roadsides; 300–1000 m.

Andropogon caricosus Linnaeus, Sp. Pl., ed. 2, 2: 1480. 1763.

Andropogon caricosus L. Sp. PI. ed. 2, 1480. 1763
Andropogon serraius Retz. Obs. 5 : 21. 1789.
Lepeocercis serrata Trin. Fund. Agrost. 203. 1820.
Sorgum caricosum Kuntze, Rev. Gen. 791. 1891.
Andropogon annulaius subrepens Hack. Notizbl. Bot. Gart. Berlin 1 : 327. 1897.
Stems 2-6 dm. tall, slender, usually branched above, decumbent and rooting at the base, glabrous at the apex; leaf-sheaths compressed, shorter than the internodes, keeled; blades up to 12 cm. long, 2-4 mm. wide, smooth beneath, usually pubescent above; racemes solitary, sometimes in 2's or 3's, 3-5 cm. long, the internodes and pedicels about one third as long as the sessile spikelets, ciliate on one margin; perfect sessile spikelet about 3 mm. long, somewhat convolute below, the first scale chartaceous-herbaceous, broadly obovate-elliptic, the manifest hispid wings ending abruptly below the apex, smooth and shining on the back which is pilose
F
below, 8-nerved, the fourth scale bearing an awn 1.5-2 cm. long; pedicellate spikelet equaling
the sessile one and similar to it, flat, more pubescent, the first scale 15-19-nerved, ciliate on
the keels.
Type locality : India.
Distribution : Introduced into Guadeloupe ; a native of the tropics of the Old World.

Perennials, Terrestrial, not aquatic, Stems nodes swollen or brittle, Stems geniculate, decumbent, or lax, sometimes rooting at nodes, Stems caespitose, tufted, or clustered, Stems terete, round in cross section, or polygonal, Stem nodes bearded or hairy, Stem internodes solid or spongy, Stem internodes hollow, Stems with inflorescence less than 1 m tall, Stems, culms, or scapes exceeding basal leaves, Lea ves mostly cauline, Leaves conspicuously 2-ranked, distichous, Leaves sheathing at base, Leaf sheath mostly open, or loose, Leaf sheath smooth, glabrous, Leaf sheath and blade differentiated, Leaf blades linear, Leaf blades 2-10 mm wide, Leaf blades mostly flat, Leaf blades mostly glabrous, Leaf blades scabrous, roughened, or wrinkled, Ligule present, Ligule an unfringed eciliate membrane, Inflorescence terminal, Inflorescence solitary, with 1 spike, fascicle, glomerule, head, or cluster per stem or culm, Inflorescence with 2 or more spikes, fascicles, glomerules, heads, or clusters per culm, Inflorescence a panicle with narrowly racemose or spicate branches, Inflorescence a panicle with digitately arranged spicate branches, Inflorescence with 2-10 branches, Inflorescence branches paired or digitate at a single node, Flowers bisexual, Flowers unisexual, Spikelets pedicellate, Spikelets sessile or subsessile, Spikelets dorsally compressed or terete, Spikelet less than 3 mm w ide, Spikelets with 2 florets, Spikelet with 1 fertile floret and 1-2 sterile florets, Spikelets paired at rachis nodes, Spikelets in paired units, 1 sessile, 1 pedicellate, Pedicellate spikelet rudimentary or absent, usually sterile, Spikelets bisexual, Spikelets unisexual, Spikelets disarticulating below the glumes, Spikelets falling with parts of disarticulating rachis or pedicel, Spikelets conspicuously hairy , Glumes present, empty bracts, Glumes 2 clearly present, Glumes equal or subequal, Glumes equal to or longer than adjacent lemma, Glumes awned, awn 1-5 mm or longer, Glume surface hairy, villous or pilose, Glumes 1 nerved, Glumes 4-7 nerved, Glume margins or apex erose-ciliate, Lemmas thin, chartaceous, hyaline, cartilaginous, or membranous, Lemma 1 nerved, Lemma glabrous, Lemma apex acute or acuminate, Lemma distinctly awned, more than 2-3 mm, Lemma with 1 awn, Lemma awn 1-2 cm long, Lemma awned from tip, Lemma awn twisted, spirally coiled at base, like a corkscre w, Lemma awn once geniculate, bent once, Lemma awn twice geniculate, bent twice, Lemma margins thin, lying flat, Lemma straight, Callus or base of lemma evidently hairy, Callus hairs shorter than lemma, Lemma surface pilose, setose or bristly, Stamens 3, Styles 2-fid, deeply 2-branched, Stigmas 2, Fruit - caryopsis, Caryopsis ellipsoid, longitudinally grooved, hilum long-linear.

Dichanthium caricosum là một loài thực vật có hoa trong họ Hòa thảo. Loài này được (L.) A.Camus mô tả khoa học đầu tiên năm 1921.

单穗草（学名：Dichanthium caricosum）为禾本科双花草属下的一个种。