Sarga plumosum (R.Br.) Spangler. Austral.
Syst. Bot. 16(3): 291 . (2003).
Classification. (GPWG 2001) : Subfamily
Replacement Name: Holcus plumosus
R. Br., Prodr. 200 (1810).
Type of Basionym or
Protologue Information: HT: R. Brown 6192, 19 Nov 1802, Australia:
Queensland: Burke District: Gulf of Carpentaria, Allen Island (Wellesley Group)
(BM; IT: K).
Recent synonyms: Sorghum grande, S. interjectum.
(books and floras): . R.Brown, Prodromus (200 as Holcus
plumosus),  G.Bentham, Flora Australiensis 7 (540 as Sorghum
plumosum),  C.A.Gardner, Flora of Western Australia 1 Gramineae
(317 as Sorghum plumosum),  M.Lazarides in J.Jessop (ed)., Flora
of Central Australia (491 as Sorghum),  D.Sharp &
B.K.Simon, AusGrass, Grasses of Australia.
 C.A.Gardner, Flora of Western Australia 1 Gramineae (315,
Pl.93 as Sorghum).
Perennial. Rhizomes absent or present, short. Culms erect, stature robust to
moderate, 100–300 cm tall, 3–7 mm diam., 4–7 -noded. Mid-culm internodes
pruinose or glabrous. Mid-culm nodes glabrous or pubescent or bearded. Lateral
branches simple or sparsely branched. Leaf-sheaths hairy. Ligule a fringed
membrane, a ciliolate membrane or a ciliate membrane, 1.5–3.7 mm long.
Leaf-blades flat or conduplicate or terete, 15–40 cm long, 4–16 mm wide.
Leaf-blade surface indumented.
Inflorescence compound, a panicle of rames. Panicle linear or lanceolate,
dense, 12.5–45 cm long, 2–5 cm wide.
Spikelets sessile, 1 in the cluster. Companion spikelets pedicelled, 1 in the
cluster. Companion spikelets developed, containing empty lemmas or male, 713 mm
long. Companion spikelet glumes muticous. Fertile spikelets 2-flowered, the
lower floret barren (rarely male), the upper fertile, comprising 1 basal
sterile florets, comprising 1 fertile floret(s), without rachilla extension,
elliptic, dorsally compressed, 6–18 mm long.
dissimilar. Lower glume ovate, cartilaginous or coriaceous, much thinner above,
without keels, 5–9 -nerved. Lower glume surface indumented. Upper glume ovate,
cartilaginous or coriaceous, without keels, 5–9 -nerved. Upper glume surface
indumented. Florets. Basal sterile florets 1, barren, without
significant palea. Lemma of lower sterile floret 80 % of length of spikelet,
hyaline, 2 -nerved.
Fertile lemma 2–3 mm
long, 1 -nerved. Lemma apex dentate or lobed, awned, 1 -awned. Median
(principal) awn 25–100 mm long overall, with a twisted column. Palea absent.
Lodicules present. Anthers 3. Grain 3.3–4.5 mm long.
Distribution: Western Australia, Northern Territory, Queensland.
Gardner, Fitzgerald, Hall, Dampier. Canning, Fortescue, Carnarvon. Northern
Territory: Darwin & Gulf, Victoria River, Barkly Tableland, Central
Australia North. Queensland: Cook, Burke, North Kennedy, South Kennedy,
Port Curtis, Leichhardt, Wide Bay, Gregory North, Mitchell, Warrego.
There are two varities
in tropical Australia, one widepread and the other only collected once.
lamina flat or loosely folded, 4–12 mm wide, herbaceous 19a. var. plumosum
Leaf lamina terete, 1–2 mm wide, indurated 19b. var. teretifolium
S. plumosum (R.Br.) P.Beauv. var. plumosum
Widespread in tropical Australia with a few
records from the subtropics. Flowers Jan.--Sept.
S. plumosum var. teretifolium
This variety has thus far only been collected
from the type locality.