Bigleaf Bristlegrass

Panicum palmifolium Willdenow ex Poiret (1816) is a nomen novum for the illegitimate later homonym P. plicatum Willdenow (1809), not Lamarck (1791), but is itself illegitimate as a later homonym of P. palmifolium J. König (1788). Both Chaemaeraphis palmifolia and Chaetochloa palmifolia are based on P. palmifolium Willdenow ex Poiret, but must be treated as nomina nova rather than new combinations.

This species is used for food and medicine.

Perennials; clums caespitose, 60-100 cm tall, with short rhizome. Blade lanceolate, pubescent below, to 40 cm long, to 6.5 cm wide, plicate; sheath keeled, papillose-hispid; ligule a ring of hairs, 1.5- 2 mm long. Panicle loose, as much as 40 cm long, spikelets crowded, branches extending into bristles of 5-15 mm long; main axis nearly glabrous. Spikelets 3-4 mm long, lanceolate, acute; glumes and lower lemma with margins hyaline; lower glume 3-5-veined, ovate, 1/3-1/2 as long as spikelet; upper glume ovate, 5-7-veined, 1/2 to as long as spikelet; lower lemma 5-veined, acuminate, with a short incurved point, enclosing a hyaline lower palea; upper lemma ovate, faintly and transversely rugose, mucronate, shiny; anther ca.1.4 mm long.

Perennial from a short knotty rhizome. Culms erect or slightly geniculate, 75–200 cm tall, 3–7(–10) mm in diam. Leaf sheaths usually sparsely hispid, margins tuberculate-ciliate near ligule, otherwise glabrous; leaf blades fusiform-lanceolate, plicate, 20–60 × 2–7 cm, glabrous or hispid, narrowed toward base, apex acuminate; ligule 2–3 mm, ciliate. Panicle 20–60 × 2–10 cm, branches up to 20 cm, laxly spreading, flexuous, some spikelets subtended by a single 5–15 mm bristle. Spikelets broadly lanceolate, 3–4 mm, acute; lower glume triangular-ovate, 1/3–1/2 as long as spikelet, obtuse to acute; upper glume ovate, 1/2–3/4 as long as spikelet, 5–7-veined, acute; lower lemma neuter, often distinctly longer than upper floret, 5-veined, tipped with a short incurved beak; lower palea narrow, hyaline, 2/3 as long as lemma; upper lemma indistinctly rugulose to almost smooth, slightly shiny, apex apiculate, green and compressed. Fl. and fr. Aug–Dec. 2n = 36, 54.

Tropics of Old World, introduced in the New World.

Tropics of the Old World. Taiwan, in shady places.

300-1800 m

Open forests, thicket margins, shady pathsides. Anhui, Fujian, Guangdong, Guangxi, Guizhou, Hainan, Hubei, Hunan, Jiangxi, Sichuan, Taiwan, Xizang, Yunnan, Zhejiang [W Africa, tropical Asia].

Panicum palmifolium J. König, Naturforscher. 23: 208. 1788.

Panicum palmifolium J. König, Naturforscher 23: 208. 1788 ["palmaefolium"]; Chamaeraphis palmifolia Kuntze; Chaetochloa palmifolia Hitchcock & Chase; Panicum neurodes Schultes; P. palmifolium Willdenow ex Poiret (1816), not J. Konig (1788); P. plicatum Willdenow (1809), not Lamarck (1791).

Perennials, Terrestrial, not aquatic, Stems trailing, spreading or prostrat e, Stems nodes swollen or brittle, Stems erect or ascending, Stems geniculate, decumbent, or lax, sometimes rooting at nodes, Stems caespitose, tufted, or clustered, Stems terete, round in cross section, or polygonal, Stem internodes solid or spongy, Stem internodes hollow, Stems with inflorescence less than 1 m tall, Stems with inflorescence 1-2 m tall, Stems, culms, or scapes exceeding basal leaves, Leaves mostly cauline, Leaves conspicuously 2-ranked, distichous, Leaf blades plicate, corrugated, Leaves sheathing at base, Leaf sheath mostly open, or loose, Leaf sheath smooth, glabrous, Leaf sheath hairy, hispid or prickly, Leaf sheath and blade differentiated, Leaf blades linear, Leaf blades lanceolate, Leaf blades ovate, Leaf blades 2 or more cm wide, Leaf blades mostly flat, Leaf blades scabrous, roughened, or wrinkled, Ligule present, Ligule a fringe of hairs, Inflorescence terminal, Inflorescence an open panicle, openly paniculate, branches spreading, Inflorescence so litary, with 1 spike, fascicle, glomerule, head, or cluster per stem or culm, Inflorescence a panicle with narrowly racemose or spicate branches, Flowers bisexual, Spikelets pedicellate, Spikelets dorsally compressed or terete, Spikelet less than 3 mm wide, Spikelets with 1 fertile floret, Spikelets with 2 florets, Spikelet with 1 fertile floret and 1-2 sterile florets, Spikelets solitary at rachis nodes, Spikelets all alike and fertille, Spikelets bisexual, Spikelets disarticulating below the glumes, Spikelets all subtended by bristles, Spikelet bristles 1-3, Spikelet bracts bristles not disarticulating with spikelets, Glumes present, empty bracts, Glumes 2 clearly present, Glumes distinctly unequal, Glumes shorter than adjacent lemma, Glume equal to or longer than spikelet, Glumes 3 nerved, Glumes 4-7 nerved, Lemmas thin, chartaceous, hyaline, cartilaginous, or membranous, Lemma similar in texture to glumes, Lemma becoming indurate, enclosing palea and caryopsis, Lemma 5-7 nerved, Lemma glabrous, Lemma rugose, with cross wrinkles, or roughened, Lemma apex acute or acuminate, Lemma awnless, Lemma margins thin, lying flat, Lemma straight, Palea present, well developed, Palea shorter than lemma, Palea 2 nerved or 2 keeled, Stamens 3, Styles 2-fid, deeply 2-branched, Stigmas 2, Fruit - caryopsis.

Setaria palmifolia is a species of grass known by the common names palmgrass, highland pitpit, hailans pitpit, short pitpit, broadleaved bristlegrass, and knotroot. In Spanish it is called pasto de palma and in Samoan vao 'ofe 'ofe. It is native to temperate and tropical Asia. It is known elsewhere as an introduced, and often invasive, species, including in Australia, New Zealand, many Pacific Islands, and the Americas.