Sorghastrum nutans*

Sorghastrum nutans* (L.) Nash. Fl. Southeast. U.S. 66 (1903).

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

Basionym and/or
Replacement Name:
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.
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

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 compound, a panicle of rames. Panicle oblong, dense, 10–35 cm
long, 5 cm wide. Rhachis fragile at the nodes.

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.

: Australasia, North America, and South America.

: Western Australia.

Western Australia:

Naturalised in one locality of south-western W.A. Flowers Mar.


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