Viola trinervata
Viola sororia
3-nerve violet, desert pansy, Rainier or sagebrush or three-nerve violet, Rainier violet, sagebrush violet, three-nerve violet
common blue violet, common or downy or woolly blue violet, northern blue violet, northern violet, northern woodland violet, violette parente, woolly blue violet
1–4, decumbent, ascending, or erect, ca. 1/2 subterranean, glabrous, from single, vertical, deep-seated caudex.
basal and cauline;
basal: 1–7, palmately compound, leaflets 3–5;
stipules adnate to petiole, forming 2 linear-lanceolate wings, unlobed, margins entire, apex of each wing free, acute;
petiole 4.5–15 cm, glabrous;
blade reniform or ovate to ± orbiculate, 2–5 × 2.5–5 cm, coriaceous, base tapered, leaflets cleft or dissected into 2–3 elliptic, lanceolate, or oblanceolate lobes 2–7 mm wide, margins usually entire, eciliate, apex acute, mucronulate, surfaces glabrous (± glaucous), abaxial surface usually with prominent vein parallel to each margin;
cauline similar to basal except: stipules lanceolate;
petiole 1–5.5 cm;
blade 1–3 × 2–4.5 cm.
basal, 1–8, ascending to erect;
stipules linear-lanceolate to broadly lanceolate, margins entire, sometimes glandular distally, apex acute;
petiole 2–25 cm, pubescent or glabrous;
blade green abaxially, unlobed, ovate or broadly ovate to reniform, 2–5 × 2–10 cm, not fleshy, base cordate, margins crenate to serrate, ciliate or eciliate, apex acute to obtuse or rounded, surfaces usually pubescent, rarely glabrous.
1.1–7 cm, glabrous.
3–25 cm, glabrous or sparsely pubescent.
sepals lanceolate, margins eciliate, auricles 0–1 mm;
petals: upper 2 often overlapping, dark reddish violet on both surfaces, lower 3 lilac, rarely white, lateral 2 bearded, with yellow patch basally and reddish violet patch distal to yellow patch, lowest 9–15 mm with yellow patch, dark reddish violet-veined, spur yellow, gibbous, 0.6–1.5 mm;
style head bearded; cleistogamous flowers absent.
sepals lanceolate to ovate, margins ciliate or eciliate, auricles 1–2 mm;
petals light to dark blue- or dark purple-violet, reddish purple, or rarely white on both surfaces, usually white basally, lowest and sometimes lateral 2 purple-veined, lateral 2 bearded, lowest bearded or beardless, 15–25 mm, spur same color as petals, gibbous, 2–3 mm;
style head beardless; cleistogamous flowers on prostrate to ascending peduncles.
ovoid, 7–12 mm, glabrous.
ellipsoid, 5–12 mm, glabrous.
tan, 3.2–4.5 mm.
beige, mottled to bronze, 1.5–2.5 mm.
= 54.
Viola trinervata
Viola sororia
In some populations of Viola trinervata the lower three petals are white with a yellow area proximally (V. B. Baird 1942).
(Discussion copyrighted by Flora of North America; reprinted with permission.)
Viola sororia is similar to V. palmata in the high degree of phenotypic plasticity. The petal color is usually light to dark blue-violet. In V. sororia forma priceana (the Confederate violet) petals are grayish white with violet veins. Viola septentrionalis was recognized by N. L. Gil-Ad (1997) based on what he considered distinct capsule and seed morphology. His assumptions were based on one to four specimens. A. Haines (2011) alluded to the variability of V. sororia and indicated that a more northern form has often been called V. septentrionalis. He suggested that range-wide patterns of variation make it difficult or impractical to separate. We currently see no valid reason to recognize V. septentrionalis.
Viola floridana was recognized by D. B. Ward (2006) as distinct from V. sororia based on being glabrous except for scattered hairs on petioles.
Viola sororia reportedly hybridizes with V. cucullata (= V. ×bissellii House), V. hirsutula [= V. ×cordifolia (Nuttall) Schweinitz], V. pedatifida var. brittoniana (= V. ×insolita House), V. pedatifida var. pedatifida (= V. ×bernardii Greene), and V. sagittata var. sagittata (= V. ×conjugens Greene).
(Discussion copyrighted by Flora of North America; reprinted with permission.)
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