Dichanthium aristatum*

Dichanthium aristatum* (Poir.) C. E.
Hubbard. Bull. Misc. Inform. 654 (1939).

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

Basionym and/or
Replacement Name:
 Andropogon
aristatus
Poir., Encycl., Suppl. 1: 585 (1811).

Type of Basionym or Protologue Information: Mauritius: 'ce'tte plante a été observée
a l'Ile-de-France, Commerson s.n. (Herb. Desfontaines).

Key references
(books and floras):
[1969] E.E.Henty, Manual Grasses New Guinea
(69), [2002] D.Sharp & B.K.Simon, AusGrass, Grasses of Australia.

Habit.
Perennial. Culms decumbent, 20–100 cm tall. Mid-culm nodes glabrous or
pubescent. Ligule an eciliate membrane, 0.6 mm long. Leaf-blades 3–25 cm long,
2–5 mm wide.

Inflorescence.
Inflorescence digitate, with ramose branches. Rhachis fragile at the nodes.

Spikelets.
Spikelets sessile, 1 in the cluster. Companion spikelets pedicelled, 1 in the
cluster. Basal sterile spikelets well-developed, 2–12 in number (lower raceme).
Companion spikelets developed, containing empty lemmas or male, 5–5.5 mm long.
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 elliptic or obovate, dorsally
compressed, 2–5 mm long.

Glumes. Glumes
dissimilar, firmer than fertile lemma. Lower glume elliptic or ovate or
obovate, chartaceous, of similar consistency above or much thinner above,
without keels, 8–10 -nerved. Lower glume surface indumented. Upper glume
lanceolate, keeled, 1-keeled. Florets. Basal sterile florets 1, barren,
without significant palea. Lemma of lower sterile floret hyaline.

Fertile lemma 3.2 mm
long, without keel, 1 -nerved. Lemma apex entire, awned, 1 -awned. Median
(principal) awn apical, 10–20 mm long overall, with a twisted column. Palea
absent. Anthers 3. Grain 1.8 mm long.

Continental
Distribution
: Africa, Temperate Asia, Tropical Asia, Australasia, Pacific,
North America, and South America.

Australian
Distribution
: Western Australia, Northern Territory, Queensland.

Western
Australia
: Gardner.
Northern Territory:
Darwin & Gulf. Queensland: Burke,
Cook, Darling Downs, Leichhardt, Mitchell, Moreton, North Kennedy, Port Curtis,
South Kennedy, Wide
Bay, Burnett.

Notes.
Native to India and SE Asia but now widely introduced in tropical areas.
Widely but sporadically naturalised in coastal, subcoastal and rarely inland
areas of Qld. Cultivated in W.A., N.T. and N.S.W. It is regarded as a useful
fodder as well as a weed where not intentionally sown. Flowers Feb.- Nov.

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