Description: Tufted or stoloniferous perennials or annuals, culms often branched.
Leaves with sheath often with hairs at the orifice, striate, smooth; ligule a ciliate, membranous rim; blade rolled or folded in bud.
Inflorescence a digitate or subdigitate arrangement of 2–15 erect or spreading spikes or spike-like racemes; spikelets usually overlapping in 2 rows along 1 side of the slender rachis.
Spikelets solitary, sessile or shortly pedicellate, disarticulating above the glumes and between any fertile florets; florets 2–7, the lowest 1–few bisexual, others sterile. Glumes unequal, keeled, acute or mucronate. Lemmas 2–7, lowest mostly 3-nerved, lateral nerves submarginal, central nerve extended into an awn, callus bearded. Palea subequal to the lemma. Grain triangular in cross section; embryo c. 50% as long as caryopsis.
Distribution and occurrence: World: c. 40 species, tropical & warm-temp. regions. Australia: 13 species (7 species native, 6 species naturalized), all mainland States.
Many Chloris species are valuable for forage in native and natural pastures, despite reports of high contents of cyanogenetic glycosides; C. gayana is an important pasture grass all over the world. Key from Wheeler et al. (1990).
Text by S. W. L. Jacobs & S. M. Hastings
| ||Key to the species|| |
|1||Callus 2.5 mm long, sharp-pointed; sterile florets usually 4–7; lemmas 5–7-nerved, margins broad, with a wing-like upper part||Oxychloris scariosa|
|Callus minute, obtuse, sterile florets usually 1–3; lemmas not winged, usually 3-nerved||2|
|2||Spikelets blunt at the apex; upper lemma(s) (of sterile florets) obtuse or truncate, notched or obscurely lobed||3|
|Spikelets acute and narrowed at the apex; upper lemma acute, acuminate, subulate or deeply divided into 2 lobes or teeth with an awn in the sinus|
Back to 1
|3||Lemma of the fertile (lowest) floret hairy on the lower and upper margins (upper margins of fertile lemma often bearded)||4|
|Lemma of the fertile floret glabrous on the lower part of the margins (but sometimes hairy above)|
Back to 2
|4||Florets 3 or 4, at least 1 bisexual, the other(s) imperfect (reduced to a lemma); strongly stoloniferous perennial; spikes frequently in 2 whorls||Chloris gayana|
|Florets 2, 1 bisexual, the other imperfect and reduced to a lemma; lower lemma apex bearded with hairs 2–3 mm long; plants annual, not stoloniferous; spikes rarely in 2 whorls|
Back to 3
|5||Lemma of the fertile floret glabrous or puberulous on the margins; upper awn usually shorter than the spikelet; spikes 3–5, each 4–10 cm long; stems usually branched||Chloris ventricosa|
|Lemma of the fertile floret pubescent on the upper margins; upper awn longer than the spikelet; spike-like racemes 6–9, each 4–20 cm long; plants often stoloniferous, stems usually unbranched|
Back to 3
|6||Spike-like racemes 3.5–9 cm long; fertile lemma (including callus and lobes) 3–5.5 mm long, usually smooth; spikelets diverging from the axis like fingers of a comb||Chloris pectinata|
|Spike-like racemes 7–20 cm long and widely spreading at maturity; fertile lemma (including callus and lobes) 2–3 mm long, scabrous; spikelets tending to be appressed to the axis|
Back to 2