Inflorescence usually 1, erect, branching divaricately above the middle; branches all alternate or the first 3 arising trichotomously from a club-shaped peduncle apex with subsequent branches alternate; peduncle stout, 2–8 mm in diameter, terete, or ± club-shaped at the apex, glabrous; bracts c. 3 mm long, ovate, membranous, white with a brown keel; flowers many, racemosely arranged and spaced on terminal branches; pedicels 2–11 mm long, erect in fruit.
Leaves of 2 kinds; outer leaves reduced to chartaceousbrown sheaths (squamae), 2 or more forming a persistent narrowly tubular base enveloping each leaf base and the peduncle base; inner leaves many, up to 25 cm long and 3 mm in diameter, ± terete, erect or drooping, often glutinous, glabrous.
Perianth segments c. 11 mm long, recurved from near the base, white, dark-keeled, with 2 yellow spots near the base; the 3 outer filaments erect and muricate, the 3 inner curving outwards above the ovary and densely shaggy-scabrid in the upper portion with retrorse yellow hairs.
Perennial glabrous herb, erect to ± decumbent, up to 90 cm tall from a small woody rhizome, acaulescent; roots many, somewhat fleshy, usually ± swollen and tapering to the tip or narrowly fusiform or terete and ± fibrous, often with root hairs producing a felted covering.
Capsule smooth or slightly rugose, without tubercles, sparsely yellow-flecked, up to c. 5.5 mm long, subglobose to somewhat 3-angular.
Seeds c. 2 per locule, sharply angled, c. 1.5 mm long, white-spotted becoming greyish-black when mature.
Like T. revoluta but leaves terete, hairless, often glutinous and bearing sand.