Digitaria diffusa Vickery. Contr. New South Wales Natl. Herb. 3: 84 (1961). \
Classification. (GPWG 2001) : Subfamily Panicoideae. Paniceae.
Type of Basionym or
Protologue Information: Australia: New South Wales: Upper Colo, Mar 1950, Vickery
s.n. (HT: NSW-11017).
Key references
(books and floras): [2002] D.Sharp & B.K.Simon, AusGrass, Grasses of
Australia, [2008] S.W.L.Jacobs, R.D.B.Walley & D.J.B.Wheeler, Grasses
of New South Wales (216).
Illustrations:
[2008] S.W.L.Jacobs, R.D.B.Whalley & D.J.B.Wheeler, Grasses of New South
Wales, 4th edn (216).
Habit.
Perennial. Rhizomes present, short. Stolons absent. Culms decumbent, stature
slender to delicate, 10–40 cm tall, 3–6 -noded. Mid-culm internodes glabrous.
Mid-culm nodes glabrous or pubescent. Lateral branches branched. Leaf-sheaths
glabrous on surface or hairy. Leaf-sheath auricles absent. Ligule an eciliate
membrane, 1–2 mm long, truncate. Leaf-blades flat or involute, (1–)2.5–5(–8) cm
long, 0.75–5 mm wide. Leaf-blade surface smooth, glabrous or indumented.
Inflorescence.
Inflorescence subdigitate, with racemose branches. Racemes 2–7, spreading, 3–7
cm long. Central inflorescence axis 1–5 cm long.
Spikelets.
Spikelets pedicelled, 2 in the cluster. 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, 1.25–2 mm long. Rhachilla internodes brief up to lowest
fertile floret.
Glumes. Glumes
thinner than fertile lemma. Lower glume ovate, membranous, 0 -nerved. Upper
glume elliptic, 1.2–1.9 mm long, membranous, without keels, 3 -nerved. Upper
glume surface indumented. Florets. Basal sterile florets 1, barren,
without significant palea. Lemma of lower sterile floret 100 % of length of
spikelet, membranous, 5–7 -nerved.
Fertile lemma 1.1–1.8
mm long, without keel. Lemma apex muticous or mucronate. Lodicules present.
Continental
Distribution: Australasia.
Australian
Distribution: Queensland, New South Wales, Victoria (extinct APC).
Queensland:
Burnett, Cook, Darling Downs, Leichhardt, Maranoa, Mitchell, Moreton, Port
Curtis, Warrego, Burke, North Kennedy. New South Wales: North Coast,
Central Coast, South Coast, Central Tablelands, North-Western Slopes,
Central-Western Slopes, South-Western Slopes, North-Western Plains. Victoria:
Midlands.
Flora
of Australia Notes. At maturity, the upper lemma of this species is
relatively smooth and shiny, whereas this structure on closely related species
is distinctly muricate.
In tropical and
subtropical wet sclerophyll forests, dry sclerophyll forests, Brigalow forests,
tropical and subtropical sub-humid woodlands, temperate sub-humid woodlands,
and semi-arid shrub woodlands. Flowers mostly Mar.-June.
