Perennial herb, 30–120 cm. or more tall. Stems erect, simple but branching profusely within inflorescence, rarely so below, patent- or somewhat retrorse-pubescent or crisped pubescent, decurrent from leaf bases. Leaves 10–35(40) x 1.5–3.5(5) mm., narrowly lanceolate or linear, margins always finely or coarsely serrate throughout or at least in upper third, glabrous, fasciculate, frequently with smaller leaves in axils. Inflorescence compactly-paniculate, composed of many spikes 2.5–5.5(8) cm. long, with flowers crowded in spikes. Bracts 3.5–5.6 mm. long, ovate, acuminate, glabrous. Calyx 2–2.5(2.8) mm. long, ovate, obtuse, glabrous. Corolla 8–10.5 mm. long, white with yellow-orange throat, tube 2–2.5 mm. long; limb 5.5–8 mm. long, glabrous, lobes c. 1–1.25(2) mm. long, oblong. Capsule c. 4 mm. long, oblong in outline.
