Swollen Fingergrass

Cattle are said to be partial to this grass when it is young, but avoid it when the inflorescence matures. It has a purplish inftorescence with nearly globose sterile lemmas.

This is a widespread species from tropical to warm-temperate regions of the world, found in weedy or disturbed places. It is tolerant of high salt concentrations. When young this grass is favored by cattle.

The form of the citation of this species should be explained. The combination is based on Andropogon barbatus Linn. (1771) which is an illegitimate name, being a later homonym of Andropogon barbatus Linn. (1759), the names being based on different plants. The epithet barbata is not, however, illegitimate in the genus Chloris and Swartz was perfectly in order in calling his plant Chloris barbata, there being no other epithet available. As the citation Chloris barbata (Linn.) Sw. is ambiguous the Code permits us to forget that Linnaeus made the illegitimate combination. Thus, Chloris barbata is regarded as a new name dating from 1797 and should be cited without acknowledgement to Linnaeus.

Chloris barbata is used as a fodder grass when young.

Culms tufted. Blade about 1.5 mm wide, siliceous on surface; ligule ciliate , about 0.3 mm long. Inflorescence a digitate spike. Spikelets 3-flowered, about 3 mm long; glumes membranous, conspicuously 1-nerved; the lower deltoid-lanceolate, about 1.2 mm long, acute; the upper narrowly lanceolate, about 2.5 mm long, shortly awned; lower floret fertile; lemma about 2.7 mm long, chartaceous, 3-nerved, midrib extending into a long awn of 4 times the length of the lemma, margins hispid, 2-toothed; palea about 2.2 mm long, membranous, with a sinus at the apex, minutely ciliate, 2-keeled, upper part oblong, lower part linear; sterile lemma 2-lobed, 3-nerved, margins siliceous; anthers about 0.5 mm long. Caryopsis, about 1.6 mm long; embryo 1/2 as long as the caryopsis.

Annual or short-lived perennial. Culms loosely tufted, ascending or decumbent at base and rooting at lower nodes, 0.2–1 m tall. Leaf sheaths keeled, glabrous; leaf blades flat or folded, 10–40 cm, 4–8 mm wide, glabrous, apex acute; ligule short, ciliate. Racemes digitate, 5–15, erect or ascending, 3–8 cm, often somewhat flexuous and purplish; rachis scabrous. Spikelets with 3 or 4 florets, 3(–4)-awned; lower glume 1.2–1.5 mm; upper glume 1.7–2.5 mm, shortly mucronate; lemma of fertile floret elliptic in side view, 1.7–2.5 mm, pilose on keel, ciliate on upper margins with 1–1.5 mm hairs; awn 4.5–7 mm; upper florets sterile, lemmas empty, inflated, overlapping to form a knob at side of fertile floret; second lemma turbinate, truncate, 1–1.5 mm, glabrous or sparsely appressed-pilose on back, awn subequaling awn of fertile floret; third (and fourth) lemmas orbicular, awn somewhat shorter. Fl. and fr. Apr–May. 2n = 20, 40.

Perennial; culms up to 1 m high, loosely tufted, stoloniferous, glabrous below the inflorescence. Leaf-blades flat, rarely involute, up to 40 cm long, 2-3 mm wide, tapering towards the apex. Inflorescence of 5-12(22) digitate, loose to spreading, purplish, feathery spikes 4-8 cm long. Spikelets 3-flowered, 3-awned; lower glume 1.2-1.5 mm long; upper glume 1.7-25 mm long; lowest lemma narrowly ovate-elliptic in side-view, 2-2.5 mm long, pallid, sparsely to densely ciliate on the margins and keel, the awn 4.5-7 mm long; callus rounded, ciliate; 2nd lemma a glabrous clavate scale 1-1.5 mm long, projecting from the side of the lowest lemma, different in shape, its awn 2.5-7 mm long; 3rd lemma also reduced to a glabrous clavate scale 1 mm long, its awn 3-5 mm long.

Distributed in the tropics of Southeast Asia, introduced elsewhere, but some authors have considered it to be a native of tropical America.

Distribution: Pakistan (Sind); widespread throughout the tropics.

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

Sea coasts, offshore islands. Guangdong, Taiwan [India, Indonesia, Japan (Ryukyu Islands), Malaysia, Myanmar, New Guinea, Pakistan, Philippines, Sri Lanka, Thailand, Vietnam; Africa, America, Australia, Pacific Islands].

Andropogon barbatum L., Mant. Pl. Att. 302. 1771, non L. 1759. Chloris inflata Link, Enum. Hort. Berol. l: 105. 1821; Senaratna Grass Ceylon ; pl. 11. 1956; Keng, l. c. 466. f. 399. 1959.

Andropogon barbatus Linnaeus, Mant. Pl. 2: 302. 1771, not Linnaeus (1759); Chloris inflata Link.

Chloris inflata Link, Enum. PI. 1: 105. 1821
Andropogon barbatum L. Mant. 302. 1771. (Type from the East Indies.) Not A. barbalum L.
1759. Chloris barbala Sw. Fl. Ind. Occ. 200. 1797. (Based on Andropogon barbatum L., 1771.) Chloris paraguayensis Steud. Syn. Gram. 204. 1854. (Type from Paraguay.)
Annual, culms erect, or decumbent at the base and rooting at the lower nodes, 15-85 cm. tall; sheaths compressed-keeled, glabrous, the margins hyaline; ligule 0.3 mm. long, minutely ciliate; blades flat, 5-10 cm. long (rarely to 25 cm. long), 2-3 mm. wide, glabrous, or sparsely hispid near the base, the margins scabrous; spikes 7-10, 3-8 cm. long, digitate, more or less flexuous, erect or nearly so, forming a rather dense purplish head; spikelets 2.3-2.5 mm. long; glumes l-nerved, purple, with hyaUne margins, sparsely scabrous on the keel, the first acuminate, 1.5-1.7 mm. long, the second abruptly acute, submucronate, 2.2-2.3 mm. long; fertile floret 2.4 mm. long, the callus prominently bearded, the lemma subobtuse, pUose on both sides of the midnerve, the margins conspicuously ciliate on the upper half, the hairs 1-2 mm. long. the awn 6-8 mm. long; rudiment composed of two reduced, club-shaped, spreading florets, 1-1.5 mm. long, the awns mostly 6-8 mm. long.
Type locality: "California"; grown from seed in the Berlin Botanic Garden, probably from Mexico.
Distribution; Waste places, Mexico and the West Indies, and southward to Argentina.

Annuals, Terrestrial, not aquatic, Stems nodes swollen or brittle, Stems erect or asce nding, 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, Stems with inflorescence less than 1 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 or blade keeled, Leaf sheath and blade differentiated, Leaf blades linear, Leaf blades very narrow or filiform, less than 2 mm wide, Leaf blades 2-10 mm wide, Leaf blades mostly flat, Leaf blades mostly glabrous, Ligule present, Ligule a fringed, ciliate, or lobed membrane, Inflorescence terminal, Inflorescence solitary, with 1 spike, fascicle, glomerule, head, or cluster per stem or culm, Inflorescence a panicle with narrowly racemose or spicate branches, Inflorescence a panicle with digitately arranged spicate branches, I nflorescence with 2-10 branches, Inflorescence branches more than 10 to numerous, Inflorescence branches 1-sided, Lower panicle branches whorled, Inflorescence branches paired or digitate at a single node, Flowers bisexual, Spikelets sessile or subsessile, Spikelets laterally compressed, Spikelet less than 3 mm wide, Spikelets with 1 fertile floret, Spikelets with 3-7 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 above the glumes, glumes persistent, Spikelets disarticulating beneath or between the florets, Rachilla or pedicel glabrous, Glumes present, empty bracts, Glumes 2 clearly present, Glumes distinctly unequal, Glumes shorter than adjacent lemma, Glumes keeled or winged, Glumes 1 nerved, Lemma similar in texture to glumes, Lemma 3 nerved, Lemma apex truncate, rounded, or obtuse, Lemma apex dentate, 2-fid, Lemma distinctly awned, more th an 2-3 mm, Lemma with 1 awn, Lemma awn less than 1 cm long, Lemma awn subapical or dorsal, Lemma awns straight or curved to base, 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, Caryopsis ellipsoid, longitudinally grooved, hilum long-linear.

Chloris barbata (syn. Chloris inflata), the swollen fingergrass or purpletop chloris, is a widespread species of flowering plant in the grass family Poaceae. It is native to drier parts of the Old World tropics and sub-tropics, and it has been introduced to the southern US, most of Latin America and the Caribbean, many tropical islands, and Australia. It is considered an invasive weed species and is host to a number of serious agricultural pest species.