Sorghastrum nutans* (L.) Nash. Fl. Southeast. U.S. 66 (1903).
Classification. (GPWG 2001) : Subfamily Panicoideae. Andropogoneae.
Basionym and/or
Replacement Name: Andropogon
nutans L., Sp. Pl. 2: 1045 (1753).
Type of Basionym or
Protologue Information: LT: Kalm s.n., USA (LINN-1211.3; ILT:
US-76596 (fragm. ex LINN)). LT designated by Hitchcock, Contr. U.S. Natl.
Herb. 12: 125 (1908); also see Veldkamp, Taxon 33: 95–97 (1984) for
a discussion of the type.
Key references
(books and floras): [2002] D.Sharp & B.K.Simon, AusGrass, Grasses of
Australia.
Habit. Perennial.
Rhizomes present, elongated. Culms erect, 50–230 cm tall, 1.5–4.5 mm diam.
Lateral branches simple. Leaf-sheaths glabrous on surface or hairy. Leaf-sheath
auricles present. Ligule an eciliate membrane, 2–5 mm long. Leaf-blades 10–50
cm long, 1–10 mm wide. Leaf-blade surface glabrous or indumented.
Inflorescence.
Inflorescence compound, a panicle of rames. Panicle oblong, dense, 10–35 cm
long, 5 cm wide. Rhachis fragile at the nodes.
Spikelets.
Spikelets sessile, 1 in the cluster. Companion spikelets pedicelled, 1 in the
cluster or 2 in the cluster. Companion spikelets represented by barren
pedicels. 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, linear or lanceolate, dorsally
compressed, 5–8 mm long.
Glumes. Glumes
dissimilar, firmer than fertile lemma. Lower glume oblong, chartaceous or
coriaceous, without keels, 7–9 -nerved. Lower glume surface indumented. Upper glume
oblong, coriaceous, without keels, 5–7 -nerved. Upper glume surface glabrous. Florets.
Basal sterile florets 1, barren, without significant palea. Lemma of lower
sterile floret hyaline, 2 -nerved.
Fertile lemma 3–5.5 mm
long, without keel, 3 -nerved. Lemma apex lobed, awned, 1 -awned. Median
(principal) awn from a sinus, 10–22 mm long overall, with a twisted column.
Palea absent. Lodicules present. Anthers 3. Grain 2.3 mm long.
Continental
Distribution: Australasia, North America, and South America.
Australian
Distribution: Western Australia.
Western Australia:
Eyre.
Notes.
Naturalised in one locality of south-western W.A. Flowers Mar.
