Carolina sunrose or frostweed Carolina sunrose or frostweed

Cistus carolinianus Walter, Fl. Carol., 152. 1788; Helianthemum carolinianum (Walter) Michaux

Herbs. Stems erect, (4–)10–30(–38) cm, stellate-pubescent, <hairs 1.5–2.5 mm>. Leaves basal, <rosette- or mat-forming>, and cauline, <relatively few, similar to basal, margins not revolute>; petiole 1–4 mm; blade spatulate to obovate or elliptic, 10–35(–60) × 5–18(–28) mm, <tapered to base, apex obtuse>, surfaces sparsely stellate-pubescent, lateral veins raised abaxially. Inflorescences terminal, scorpioid cymes; chasmogamous flowers 1–3 per cyme, cleistogamous rarely produced, <flowering 1–3 months later than chasmogamous>. Pedicels 4–15(–24) mm; bracts 2.5–6 × 0.5–1 mm. Chasmogamous flowers: outer sepals lanceolate, 3–6(–7.5) × 0.6–1.2 mm, inner sepals ovate, 7–12 × 4–6 mm, apex acuminate; petals broadly spatulate, 8–18 × 8–15 mm; capsules 6–9 × 4.5–9 mm, glabrous. Cleistogamous flowers: outer sepals linear, 1.6–2.8 × 0.4 mm, inner sepals ovate, 3–4.5 × 1.6 mm, apex acute; capsules not seen.

Flowering Mar–May. Dry to mesic pine savannas and flatwoods, sandy pine-oak woodlands, stable alluvial dunes; 0–200 m; Ala., Ark., Fla., Ga., La., Miss., N.C., S.C., Tex.

Crocanthemum carolinianum is one of the more distinctive members of Crocanthemum because of its short stature, basal rosettes, relatively large leaves, nonrevolute leaf margins, and long-stellate hairs on stems. Unlike other eastern species, it rarely produces cleistogamous flowers (less than 1% of specimens examined, according to H. S. Daoud and R. L. Wilbur 1965, all in Florida).