Balduina

Nuttall

Gen. N. Amer. Pl. 2: 175. 1818.

Etymology: For William Baldwin, 1779–1819, American botanist
Treatment appears in FNA Volume 21. Treatment on page 419. Mentioned on page 5, 415.

Annuals or perennials, 30–100 cm (gland-dotted). Stems erect, simple or branched (terete or angled), glabrous or hairy. Leaves cauline; alternate; sessile; blades linear, linear-spatulate, or spatulate, margins entire, faces glabrous or ± hairy. Heads borne singly or in loose, corymbiform to paniculiform arrays. Involucres hemispheric to broadly campanulate, 6–25 mm diam. Phyllaries persistent, 30–50 in 3–5 series (distinct, lanceolate to ovate, unequal). Receptacles slightly convex, deeply pitted (pits collectively forming honeycombed structure, each pit ± enveloping a disc floret, pit borders irregularly toothed to entire), epaleate (pits sometimes interpreted as formed from connate paleae). Ray florets 8–22, neuter; corollas yellow (tubes glabrous or hairy, laminae spatulate, abaxially hairy, adaxially glabrous). Disc florets 30–190, bisexual, fertile; corollas yellow, orange-red, or purple (at least tips), tubes shorter/longer than funnelform throats, lobes 5, deltate (abaxially hairy; stamens pale yellow; style-branch appendages subulate, papillate). Cypselae obconic, villous; pappi persistent, of 7–12 scales. x = 18.

Distribution

se United States.

Discussion

Species 3 (3 in the flora).

Key

1 Annuals (taprooted); cauline leaves linear, 0.5–1.9(–2.5) mm wide; outer phyllaries lanceolate, 0.6–1.7 mm wide, apices acuminate; pappus scales obovate to orbiculate,0.3–0.6 mm Balduina angustifolia
1 Perennials (fibrous rooted); cauline leaves linear-spatulate, 2–7 mm wide; outer phyllaries ovate, 1.7–3.1 mm wide, apices acute; pappus scales lanceolate, 1.3–2.2 mm > 2
2 Basal leaves spatulate, 2.8–10.4 cm; disc corollas yellow to orange-red Balduina uniflora
2 Basal leaves linear-spatulate, 7–32 cm; disc corollas dark purple (at least tips) Balduina atropurpurea