Triodia irritans R.Br.

Plants forming hummocks 0.3–1 m high, usually compact and spherical. Flowering culms 0.6–1 m high. Leaves: sheath smooth or densely papillose on back, with scaberulous (rarely ciliate) upper margins; orifice pubescent or (especially when young) with fine, straight hairs 2–4 mm long; blade straight, folded, 5–25 cm long, 0.5–1 mm wide, scabrous-papillose adaxially, with abaxial surface closely nerved all over, sometimes glaucous. Panicles oblong or narrow-elliptic, usually dense, 5–12 (–19) cm long, 1.5–4 cm wide, often subtended and partially enclosed by a flag leaf with reduced blade; axis triquetrous; branches 0.5–7.5 cm long, often further divided. Spikelets solitary or paired, often cuneate, 11–30 mm long, 3–7 (–10) mm wide, 4–15-flowered; pedicel 0.3–3 cm long; rachilla internodes 1.5–2 mm long or lower ones shorter. Glumes ±equal or upper glume 2–3 mm longer, lanceolate, 9–26 mm long, entire and acuminate, or 2-lobed then often mucronate, scarious or cartilaginous, 3–5 (–7)-nerved, obtusely carinate, glabrous. Callus blunt, minute. Basal lemma lanceolate-ovate or elliptic, 6–12 mm long excluding awnlet, acuminate, shortly 2-lobed, scarious or cartilaginous, 9-nerved (in 3 groups of 3), hirsute on lower parts; margins narrow, hyaline; lobes minute or 1–1.8 mm long, sometimes unequal; awnlet arising in sinus, 0.5–6 mm long. Palea shorter than lemma, thickened and smooth basally, entire or notched and sometimes beaked, scarious or cartilaginous, body sometimes hairy towards base; flaps partly scabrous-pubescent. Anthers 3–4 mm long.

Confined to rocky hillslopes and usually common todominant in those habitats. Found chiefly in skeletal or shallow, stony or rocky soils onquartzite and granite hills and ranges, often in creeks, rock crevices, gulliesand valleys; also limestone soils, saline flats, coastal dunes above a high cliff,sand plains, flats in red sandy loam. 

Can be grown by seedlings.