Triodia dielsii

Triodia dielsii (C.E. Hubb.) M. Lazarides. Austral. Syst. Bot. 10: 431 (1997).

Classification. (GPWG 2001) : Subfamily Chloridoideae. Triodeae.

Basionym and/or
Replacement Name:
C.E. Hubb., Bull. Misc. Inform. Kew, 1941: 27 (1941).

Type of Basionym or
Protologue Information
: Australia: Western Australia: Avon District:
Tammin, in dry open sandy thickets, 250 m, 25 Oct 1901, Diels 5085 (HT:
B; IT: K).

Key references
(books and floras):
[1952] C.A.Gardner, Flora of Western Australia 1
Gramineae (81 as Plectrachne dielsii), [2002] D.Sharp &
B.K.Simon, AusGrass, Grasses of Australia.

[2005] K.Mallet (ed.), Flora of Australia 44B: Poaceae 3 (Fig.

Perennial. Culms erect, 60–250 cm tall. Lateral branches simple. Leaf-sheaths
glabrous on surface. Leaf-sheath auricles absent. Ligule a fringe of hairs.
Leaf-blades aciculate, conduplicate, 15–50 cm long, 1–2 mm wide. Leaf-blade
surface glabrous.

Inflorescence compound, a panicle. Panicle 24–30 cm long, 4–7 cm wide.

Spikelets pedicelled. Fertile spikelets many flowered, with at least 2 fertile
florets (3–4), comprising 3–4 fertile floret(s), with diminished florets at the
apex, elliptic, laterally compressed, 10–15 mm long.

Glumes similar. Lower glume elliptic, chartaceous or scarious, without keels,
3–9 -nerved. Lower glume surface glabrous. Lower glume apex muticous or
mucronate. Upper glume elliptic, 6–14 mm long, chartaceous or scarious, without
keels, 3–9 -nerved. Upper glume surface asperulous, glabrous. Upper glume apex

Fertile lemma 5–11 mm long, without keel, 3–11 -nerved. Lemma surface
indumented. Lemma apex lobed, awned, 3 -awned. Median (principal) awn 8–10 mm
long overall. Lateral lemma awns present. Palea 2 -nerved. Lodicules present.
Anthers 3.

: Australasia.

: Western Australia.

Western Australia:
Irwin, Avon.

Distinguished by its extremely robust habit; large spreading panicle; loosely
few-flowered spikelet with shorter glumes; shortly awned lemmas with five
linear series of long white hairs; hairy paleas with horizontal and antrorse
scaberula on the keels. P. dielsii resembles P. danthonioides in
habit, panicle, and indumentum of lemma and palea, but lacks the foliage
indumentum of that species and has much shorter lemma awns.

South-West Province of W.A. On sandplains and near gorges, in white or grey
sand over sandstone or with lateritic gravel; flowers July-Sept.


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