Panicum effusum

Panicum effusum R. Br. Prodr. 191

Classification. (GPWG 2001) : Subfamily
Panicoideae. Paniceae.

Type of Basionym or
Protologue Information
: HT: R. Brown 6105, Australia (BM; IT: K).

Key references
(books and floras):
[1810]. R.Brown, Prodromus (191), [1878]
G.Bentham, Flora Australiensis 7 (488), [1952] C.A.Gardner, Flora of
Western Australia
1 Gramineae (258), [1981] M.Lazarides in J.Jessop
(ed)., Flora of Central Australia (472), [2002] D.Sharp & B.K.Simon,
AusGrass, Grasses of Australia, [2006] J.Jessop, G.R.M.Dashorst,
F.M.James, Grasses of South Australia (461), [2008] S.W.L.Jacobs,
R.D.B.Walley & D.J.B.Wheeler, Grasses of New South Wales.

[2006] J.Jessop, G.R.M.Dashorst, F.M.James, Grasses of South Australia  (461, fig. 393 as var. effusum), [2008]
S.W.L.Jacobs, R.D.B.Whalley & D.J.B.Wheeler, Grasses of New South Wales,
4th edn (315).

Habit. Perennial. Rhizomes present. Stolons absent. Culms erect or
geniculately ascending, 2–100 cm tall, 2–7 -noded. Mid-culm internodes
glabrous. Mid-culm nodes glabrous or pubescent. Lateral branches simple or
sparsely branched. Leaves mostly basal. Leaf-sheaths hairy. Leaf-sheath
auricles absent. Ligule a fringed membrane, a ciliate membrane, 1 mm long.
Leaf-blades linear, flat or involute, 5–25 cm long, 2–6 mm wide. Leaf-blade
surface smooth or scabrous, indumented.

Inflorescence compound, a panicle. Panicle oblong, effuse, 8–50 cm long, evenly
furnished or with spikelets clustered towards branch tips.

Spikelets pedicelled. 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, lanceolate or
ovate, dorsally compressed, 2–3 mm long. Rhachilla internodes elongated between

Glumes. Glumes
thinner than fertile lemma. Lower glume ovate, membranous, without keels, 3–5
-nerved. Lower glume apex muticous. Upper glume lanceolate or ovate, 2.2–2.8 mm
long, membranous, without keels, 5 -nerved. Florets. Basal sterile
florets 1, barren, with palea or without significant palea. Lemma of lower
sterile floret 90 % of length of spikelet, membranous, 7 -nerved, muticous.

Fertile lemma 1.5–2.2
mm long, without keel. Lemma apex muticous. Anthers 3.

: Tropical Asia and Australasia.

: Western Australia, Northern Territory, South Australia,
Queensland, New South Wales, Victoria, Norfolk I.

Western Australia:
Fitzgerald. Fortescue, Ashburton, Austin. Coolgardie. Northern Territory:
Darwin & Gulf, Victoria River, Central Australia South. South Australia:
North-western, Lake Eyre, Nullabor, Gairdner-Torrens Basin, Flinders Ranges,
Eastern, Eyre Peninsula, Northern Lofty, Murray, Yorke Peninsula, Southern
Lofty, South-eastern. Queensland: Burke, Burnett, Cook, Darling Downs,
Leichhardt, Maranoa, Mitchell, Moreton, North Kennedy, Port Curtis, South
Kennedy, Warrego, Wide Bay, Gregory North. New South Wales: North Coast,
Central Coast, South Coast, Northern Tablelands, Central Tablelands, Southern
Tablelands, North-Western Slopes, Central-Western Slopes, South-Western Slopes,
North-Western Plains, South-Western Plains, North Far Western Plains, South Far
Western Plains. Victoria: East Gippsland, Eastern Highlands, Gippsland
Plain, Grampians, Midlands, Murray Mallee, Riverina, Volcanic Plain, Wimmera.

Notes. In tropical
and subtropical wet sclerophyll forests, Brigalow forests, tropical and
subtropical sub-humid woodlands, temperate sub-humid woodlands, semi-arid shrub
woodlands, arid and semi-arid low woodlands, arid tussock grasslands, and arid
hummock grasslands. Flowers throughout the year.


AVH 2011


Scratchpads developed and conceived by (alphabetical): Ed Baker, Katherine Bouton Alice Heaton Dimitris Koureas, Laurence Livermore, Dave Roberts, Simon Rycroft, Ben Scott, Vince Smith