Tropical Reed

This is a very robust species found in warm parts of the Old World. It has stiffer, more scabrous leaf blades and smaller spikelets with shorter callus hairs than Phragmites australis.

The name "Arundo vallatoria Linnaeus" (Herb. Amboin. 15. 1754) belongs here, but was not validly published (see Art. 34 Ex. 2 of the Saint Louis Code), and hence neither was the combination "Phragmites vallatoria (Linnaeus) Veldkamp" (Blumea 37: 233. 1992).

Phragmites karka occurs in swamps and beside streams. It is said to be poisonous to cattle (Duthie) but in any case it is far too course for fodder.

For most of their range these two species of Phragmites are allopatric. Phragmites austrails is a temperate species while Phragmites karka is tropical. Pakistan lies on the ecotone, and taxonomic problems are therefore considerable. It is probable that introgression occurs in this region and as a result determination of specimens is largely arbitrary. The measurements given above do not always apply and for the purposes of this Flora considerable importance is attached to the scabridity of the leaves.

Tall reed. Ligule 0.3 mm long, upper margin fimbriate, blade up to 1 cm wide. Panicle large, dense. Spikelets several-flowered, 12 mm long; glumes lanceolate, chartaceous; the lower 3-4 mm long, 1-nerved, apex rounded, base attenuate; the upper 4-5 mm long, 3-nerved; lemma 5-10 mm long, chartaceous, 3-nerved, lanceolate, glabrous; callus elongated with silky hairs; palea 3 mm long, 2-keeled, margins minutely ciliate, apex truncate.

Robust perennial from an extensive creeping rhizome. Culms very stout, often woody, 4–6 m tall, 1.5–2.5 cm in diam. Leaf sheaths greenish, glabrous; leaf blades erect-ascending, up to 80 × 2–3 cm, abaxial surface scabrous, apex stiff, long acuminate; ligule 0.5–1 mm, ciliolate. Panicle 30–50 × 10–20 cm; branches of lowermost whorl bare of spikelets toward base, ± glabrous at insertion. Spikelets 10–12 mm, florets 4–6; glumes lanceolate-elliptic, obtuse to acuminate, lower glume up to 1/2 length of lowest lemma, 2.5–4 mm, upper glume 3.5–5 mm; lowest lemma narrowly elliptic, 7–12 mm; floret callus with hairs 4–8 mm; bisexual lemmas linear-lanceolate, 8.5–10 mm, apex long attenuate. Fl. and fr. autumn. 2n = 24, 36, 38, 48.

Perennial reed, with creeping rhizomes. Culms erect, up to 10m high. Leaf-blades 30-80 cm long and 12-40 nun wide, glabrous, rough to the touch beneath (at least in the upper half), the tips attenuate and stiff (occasionally almost smooth or with filiform tips). Panicle 30-50 cm long, 10-20 cm wide, the lowest node often many-branched in a whorl, the branches bare of spikelets for some distance from their base. Spikelets 9-12 mm long, the rhachilla-hairs 4-7 mm long, rather sparse; lower glume just over half as long as the upper; upper glume narrowly elliptic to very narrowly elliptic, 4-6 mm long, acute to subacute; lowest lemma very narrowly elliptic, 7.5-12 mm long; fertile lemmas very narrowly lanceolate, 85-11 mm long.

Nepal, India, Ceylon, S.E. Asia, Australia.

India, Burma, Malaysia, China, and extening to Australia and Japan.

Fujian, Guangdong, Guangxi, Hainan, Sichuan, Taiwan, Yunnan [Cambodia, India, Indonesia, Japan, Laos, Malaysia, Myanmar, New Guinea, Philippines, Sri Lanka, Thailand, Vietnam; Africa, N Australia, Pacific Islands].

Distribution: Pakistan (Sind, Baluchistan, Punjab, N.W.F.P., Gilgit & Kashmir); tropical Africa, Polynesia, northern Australia and tropical Asia.

? m

Fl. & Fr. Per.: April-November.

Warm swampy valleys and river banks; under 1000 m.

Arundo karka Retzius, Observ. Bot. 4: 21. 1786; A. roxburghii Kunth; Phragmites cinctus (J. D. Hooker) B. S. Sun; P. roxburghii (Kunth) Steudel; Trichoon roxburghii (Kunth) Wight.

Perennials, Aquatic, leaves emergent, Terrestrial, not aquatic, Rhizomes present, Rhizome elongate, creeping, stems distant, Stems nodes swollen or brittle, Stems erect or a scending, Stems terete, round in cross section, or polygonal, Stems branching above base or distally at nodes, Stem internodes hollow, Stems with inflorescence 1-2 m tall, Stems with inflorescence 2-6 m tall, Stems, culms, or scapes exceeding basal leaves, Leaves 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 disarticulating from sheath, deciduous at ligule, Leaf blades linear, Leaf blades lanceolate, Leaf blades 1-2 cm wide, Leaf blades 2 or more cm wide, Leaf blades mostly flat, Leaf blades mostly glabrous, Leaf blades scabrous, roughened, or wrinkled, Ligule present, Ligule a fringed, ciliate, or lobed membrane, Inflorescence terminal, Inflorescence an open panicle, openly paniculate, branches spreading, Inflorescence solitary, with 1 spike, fascicle, glomerule, head, or cluster per stem or culm, Inflorescence branches m ore than 10 to numerous, Peduncle or rachis scabrous or pubescent, often with long hairs, Flowers bisexual, Spikelets pedicellate, Spikelets laterally compressed, Spikelet less than 3 mm wide, Spikelets with 2 florets, Spikelets with 3-7 florets, Spikelets with 8-40 florets, Spikelets solitary at rachis nodes, Spikelets all alike and fertille, Spikelets bisexual, Spikelets disarticulating above the glumes, glumes persistent, Spikelets disarticulating beneath or between the florets, Spikelets conspicuously hairy , Rachilla or pedicel hairy, Glumes present, empty bracts, Glumes 2 clearly present, Glumes distinctly unequal, Glumes shorter than adjacent lemma, Glumes 3 nerved, Glumes 4-7 nerved, Lemma similar in texture to glumes, Lemma 3 nerved, Lemma glabrous, Lemma apex acute or acuminate, Lemma awnless, Lemma margins inrolled, tightly covering palea and caryopsis, Lemma straight, Palea present, well developed, Palea membranous, hyaline, Palea shorter than lemma, Stamens 3, S tyles 2-fid, deeply 2-branched, Stigmas 2, Fruit - caryopsis.