Common name
Swamp Millet

Derivation
Isachne R.Br., Prodr. 196 (1810); from the Greek isos (equal) and achne (chaff or scale), glumes more or less similar.

globosa- from the Latin globus (sphere) and -osa (abundance). Spikelets spherical.

Published in
Rev. Gen. Pl. 2: 778 (1891).

Common synonyms
Isachne australis R.Br.

Habit
Annual or perennial. Glands annular. Culms erect or geniculately ascending or decumbent or prostrate, 10–90 cm tall, rooting from lower nodes. Leaf-sheaths glabrous on surface or pilose. Leaf-sheaths outer margin hairy. Ligule a fringe of hairs, 1–4 mm long. Leaf-blade base cuneate or broadly rounded or cordate. Leaf-blades linear or lanceolate or ovate, 1–14 cm long, 3–20 mm wide. Leaf-blade margins unthickened or cartilaginous, scaberulous.

Inflorescence
Inflorescence compound, a panicle. Panicle open, ovate, 1–15 cm long, 1–8 cm wide. Primary panicle branches 2–5 cm long. Panicle branches capillary.

Spikelets
Spikelets solitary. Pedicels filiform, flexuous, eglandular or glandular. Fertile spikelets 2-flowered, comprising 1 fertile floret, without rhachilla extension, orbicular, terete or dorsally compressed, 1.5–2.4 mm long, 1–1.2 mm wide, breaking up at maturity. Spikelets disarticulating below each fertile floret.

Glumes
Glumes deciduous, similar, thinner than fertile lemma. Lower glume elliptic to orbicular, 1.4–2.2 mm long, equalling upper glume, 80–100% of length of spikelet, membranous, 5–7-nerved. Lower glume surface glabrous or puberulous, hairy at apex. Lower glume apex obtuse. Upper glume oblong or ovate, 1–2.1 mm long, 75–100% of length of spikelet, membranous, 7–9-nerved. Upper glume surface glabrous or puberulous, hairy at apex. Upper glume apex obtuse.

Florets
Basal sterile floret 1, with palea, separately deciduous. Lemma of lower sterile floret elliptic to ovate, 1.5–2.2 mm long, 100% of length of spikelet, chartaceous or cartilaginous, 5-nerved, glabrous. Fertile florets bisexual or female. Fertile lemma ovate or orbicular, 1–1.8 mm long, coriaceous, of similar consistency on margins, 5–7-nerved. Lemma lateral nerves obscure. Lemma surface glabrous or puberulous. Lemma margins involute. Lemma apex obtuse. Palea coriaceous, 2-nerved. Anthers 3, 1.4–1.6 mm long. Grain with adherent pericarp.

Continental Distribution:
Temperate Asia, Tropical Asia, Australasia, Pacific.

Australian Distribution:
Northern Territory, South Australia, Queensland, New South Wales, Victoria.

Northern Territory: Darwin & Gulf. South Australia: Northern Lofty, Murray, Southern Lofty. Queensland: Cook, North Kennedy, South Kennedy, Port Curtis, Leichhardt, Burnett, Wide Bay, Darling Downs, Moreton. New South Wales: North Coast, Central Coast, South Coast, Northern Tablelands, Central Tablelands, South-Western Slopes. Victoria: Wannon, Grampians, Riverina, Midlands, Otway Plain, Eastern Highlands, Gippsland Plains, East Gippsland.

Classification. (GPWG 2001):
Panicoideae: Isachneae

Notes
Native. Regarded as a good fodder species. Flowers throughout the year.