Chrysopogon Fund. Agrost. 188 (1820).
Derivation:. From Greek chrysos (golden) and pogon (beard), alluding to the golden hairs on the inflorescence.
Syn: Vetiveria Bory.
Taxonomic revisions, nomenclatural references:. S.T.Blake, Papers Dept. Biol. University Qld, 2(3): 4–18 (1944); J.F.Veldkamp, Austrobaileya 5: 503–533 (1999).
Key references (keys and floras):. G.Bentham, Flora Australiensis 7: 536–539 (1878); C.A.Gardner, Flora of Western Australia 1 Gramineae 320–323 (1952) and 324 asVetiveria; J.W.Vickery, Flora of New South Wales, Gramineae 19: 33–37 (1961); E.E.Henty, Manual Grasses New Guinea 50–51 (1969) and 190 asVetiveria; M.Lazarides, Tropical Grasses S.E. Asia 26–28 and 78–79 asVetiveria (1980); M.Lazarides, Flora of Central Australia 491–492 (1981); J.C.Tothill and J.B.Hacker, Grasses of Southern Queensland 160–162 (1983) and 430–431 asVetiveria; J.P.Jessop, Flora of South Australia 4: 1986–1987 (1986); B.K.Simon, Flora of the Kimberley Region 1141–1142 (1992) and 1242–1243 asVetiveria; B.K.Simon, Key to Australian Grasses 74 and 175 asVetiveria (1993); S.W.L.Jacobs and C.A.Wall, Flora of New South Wales 4: 437–438 and 438 as Vetiveria (1993); D.Sharp and B.K.Simon, AusGrass (2002); J.P.Jessop, Grasses of South Australia 511–513 (2006); S.W.L.Jacobs, R.D.B.Whalley & D.J.B.Wheeler, Grasses of New South Wales, 4th Ed, 185–187 (2008).
W.D.Clayton & S.A.Renvoize, Genera Graminum (1986), genus (589 & 590).
Native. 43 species, from tropical and subtropical regions. 11 species in Australia, WA, NT, SA, Qld, and NSW. Also New Guinea and Malesia.
Habit. Annual or perennial, rhizomatous or stoloniferous or tufted or decumbent. Leaf blades narrow (often harsh and glaucous). Ligule a fringed membrane (short) or a fringe of hairs.
Inflorescence. Inflorescence paniculate (the branches usually with terminal triads of spikelets, but sometimes with a long-pedicel/short-pedicel pair below the triad), an open panicle with branches ending in racemes of paired spikelets, open (with whorls of slender, persistent branches). Spikelet-bearing axes much reduced (usually to a single joint and the terminal triad, but sometimes with a long-pedicel/short-pedicel pair below), with heteromorphic spikelets (pedicellate spikelets flattened dorsally, awnless or not, often purple: often the sessile spikelet pallid or yellowish), disarticulating at joints (beneath the triad, and beneath the pairs when present). Internodes disarticulating obliquely.
Spikelets. Spikelets laterally compressed, 2 flowered, with 1 fertile floret, awned, in triplets or in triplets and paired, sessile and pedicelled, in pedicelled/sessile combinations; sessile spikelet with lower incomplete floret. Fertile spikelets falling with glumes.
Glumes. Glumes more or less equal, long relative to adjacent lemmas, awned and awnless (upper glume often awned) or awnless. Lower glume two-keeled or not two-keeled, convex on back (or keeled upwards, sometimes with spinulose margins), relatively smooth, 5–7 nerved. Upper glume 3–5 nerved.
Florets. Lower incomplete floret(s) sterile. Lemmas awnless, 2 nerved, more or less equalling fertile lemmas, similar in texture to fertile lemmas (hyaline), not becoming indurated. Fertile florets 1. Lemmas less firm than glumes (hyaline), not becoming indurated, entire at apex or incised, when two-lobed not deeply cleft (bidentate), awned, 1–3 nerved, glabrous. Awns 1, from a sinus or apical, geniculate, hairless (glabrous) or hairy, much shorter than body of lemma to much longer than body of lemma. Palea present or absent, when present conspicuous and relatively short or very reduced, nerveless. Lodicules 2. Stamens 3. Grain compressed laterally. Hilum short. Embryo large. Pedicels free of rachis. Pedicelled spikelets present, similar in shape to sessile spikelet, sterile or male, with glumes, with proximal incomplete florets, 2 floreted.
Kranz Anatomy. C4.
2n = 20 and 40.
Habitat. Mesophytic, xerophytic (from subdesert to rainforest). On poor soils, often in disturbed ground. Species of open habitats.
Classification. Panicoideae; Andropogoneae.
Notes. The separation of Chrysopogon and Vetiveria is somewhat arbitrary, particularly in Australia (Clayton and Renvoize, 1986). The revision of Veldkamp (1999), placing the two genera together, is now generally accepted (B.K.Simon).
Types Species. C. gryllus (L.) Trin.
Biogeographic Element. Clifford & Simon 1981, Simon & Jacobs 1990: Gondwanan.