Rhodora 59: 53. 1957.
Herbs short-lived perennial (rarely biennial or annual), single- or multi-stemmed, (1.2–)2–3(–3.5) dm, usually unbranched, rarely branched distally; from taproot or fibrous root cluster. Stems erect, sometimes laxly so, to nearly decumbent, glabrous. Leaves alternate; sessile or subsessile, or with narrowed petiolelike base to 2 mm; blade obovate or elliptic, sometimes becoming scalelike proximally, (5–)8–23 × (2–)3–8(–9) mm, base cuneate, apex rounded, obtuse, or acute, surfaces glabrous. Racemes loosely cylindric, open, elongate, 7–10(–15) × 1–1.5 cm; peduncle 1–2(–2.5) cm; bracts deciduous, ovate. Pedicels 3–4(–5) mm, glabrous. Cleistogamous flowers present in racemes usually below, rarely just above, soil surface, sometimes in proximal leaf axils later in season. Flowers pink to pale purple, 4–6 mm; sepals ovate or elliptic, 1.1–2 mm; wings elliptic, ovate, or obovate, (3.3–)4–5 × (1.5–)2–2.7 mm, apex obtuse to bluntly rounded; keel 3–4 mm, crest 2-parted, with 2–4 entire or divided lobes on each side. Capsules broadly ellipsoid, 2–3.5 × 2–3 mm, margins narrowly winged, wings equal, crenate. Seeds 1.5–2 mm, pubescent; aril 1 mm, somewhat helmetlike, lobes to 1/4 length of seed.
Phenology: Flowering spring–summer.
Habitat: Wet flatwoods and savannas, sandy mesic hills, bogs, acidic swamps.
Elevation: 0–100 m.
Ala., Fla., Ga., La., Miss., Tex.
Polygala crenata is known only from the East Gulf Coastal Plain.