Atlantic J. 1: 176. 1833.
Perennials. Stems decumbent to ascending, simple or few- to much-branched, 20–60 cm, sparsely to moderately glandular-puberulent. Leaves: blade lanceolate to lanceolate-ovate or oblong, 8–25 × (1–)3–8(–13) mm, margins with (1 or)2–4 pairs of sharp teeth distally, apex acute, surfaces sparsely to densely glandular-puberulent. Pedicels slender, (5–)10–25(–30) mm, length 0.8–1.8 times bract, densely glandular-puberulent to glandular-pubescent; bracteoles (1 or)2, 4–4.5 mm. Flowers: sepals distinct, linear-lanceolate, 5–7 mm; corolla 10–13 mm, tube yellowish brown, veins yellow or brownish yellow, limb white; style 3–5 mm. Capsules subglobular to ovoid, 1.5–2.5 × 1–1.3 mm. Seeds 0.3–0.4 mm. 2n = 28.
Phenology: Flowering Apr–Jun.
Habitat: Sandy pinelands, oak barrens, sandy stream banks.
Elevation: 0–200 m.
Ala., Ark., Del., Fla., Ga., La., Okla., Tenn., Tex.
Gratiola brevifolia is morphologically variable. In parts of its range, narrow-leaved plants approach G. ramosa and some broad-leaved plants approach G. viscidula. A population of G. brevifolia in Delaware is disjunct from the nearest conspecific population by more than 800 km (W. M. Knapp and D. Estes 2006).