Gram. Essenze: 12 (1909).- Type: Kotschy 250, Sudan (iso- K, WAG).
Cymbopogon giganteus var. inermis Clayton, Kew Bull. 19: 454 (1965).- Type: Rossetti 61/282, Mauritania (holo- K);
Cymbopogon caesius ssp. giganteus (Chiov.) Sales, Fl. Zambesiaca 10(4): 77 (2002).
Regional litterature: FTA 9: 288 (1919); Fl. Agr. Congo Beige 1: 148 (1929); FWTA: 482 (1972); Ghana grasses: 229 (1977); FTEA: 763 (1982); Gram. Togo: 185 (1983); Fl. Mauritania: 419, 435, fig (1991); Gram. Cameroun: 448, fig. 98 (1992) ; Poac. CI: 538, fig. (1995); Fl. Ethiopia & Eritrea 7: 329, fig. (1995); Pl. Mauritanie: 307 (1998); Poac. Niger: 566, fig. (1999); Fl. Zambesiaca 10,4 : 77, fig (2002); Fl. Bénin: 194, fig. (2006); Fl. Guinée: 454 (2009); Fl. Guinea Bissau: 135 (2008); Pl. Burkina Faso: 78 (2012); Fl. Chad (2013); Pl. Sudan & S Sudan: 124 (2015)
Description:
* Stout erect aromatic perennial bunchgrass, 1.5-2.5 m high with numerous flowering branches. Culm stout, sometimes shortly rhizomatous. Leaves aromatic with a lemon-like scent when crushed, long linear, 15-60 cm long, 8-30 mm wide, flat, glaucous, glabrous, finely nerved with a distinct mid nerve and smooth margins; base broadly rounded, lobed and clasping the culm; ligule a short reddish brown membrane of 0.3 mm long; sheath glabrous. Roots frequently yellowish, stout coarse and fibrous.
* Inflorescence in an extended linear compound panicle, 20-70 cm long, composed of terminal and axillary paired racemes, subtended by spatheoles. Sometimes inflorescence globular (Pereira 1353). Spatheole lanceolate, 1-2 cm long. Racemes deflexed, 1-1.5 cm long; rachis fragile with hairs 0.5-1 mm long; internodes linear, 2.5-3 mm long; bases flattened, sub equal, 0.5-1.5 mm long. Pedicels linear, ciliate.
* Sessile spikelet elliptic 3.5-5 mm long, glabrous; callus obtuse pilose. Lower glume oblong, membranous, narrowly winged, with a broad median v-shaped groove. Upper lemma linear, bifid to the middle; awn shortly geniculate, 10-17 mm long with a distinct twisted glabrous column. Pedicelled spikelets male, narrowly lanceolate, 3.5-5 mm long, chartaceous, glabrous.
Note: The awnless variety var. inermisis is confined to Mauritania and Mali; C. giganteus and C. caesius integrade completely but it seems unreal to unite them; in practice separation about a leaf-widthof of 8 mm corelates tolerably well with observed differences in stature and ligule-length.