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common blue violet, common or downy or woolly blue violet, northern blue violet, northern violet, northern woodland violet, violette parente, woolly blue violet

Canada violet, Canada white violet, Canadian violet, Canadian white violet, rugose violet

Habit Plants perennial, acaulescent, not stoloniferous, 5–50 cm; rhizomes thick, fleshy. Plants perennial, caulescent, not stoloniferous, 3–46(–60) cm, with branching rhizomes forming colonies or not.
Stems

1–3(4), usually erect to ascending, glabrous or puberulent, from fleshy or subligneous rhizome.

Leaves

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.

basal and cauline;

basal: 1–5;

stipules ± oblong, ovate, or lanceolate, margins entire, sometimes glandular, apex acuminate to cuspidate;

petiole 1.1–23 cm, glabrous or puberulent;

blade ovate to broadly ovate or ovate-reniform, 0.7–12.4 × 0.9–11.1(–12.3) cm, base cordate, subcordate, or truncate, margins crenate, crenulate, or serrulate, ciliate (sometimes only on proximal 1/2) or eciliate, apex acute to acuminate, surfaces glabrous or puberulent (often only on veins);

cauline similar to basal except: stipules also deltate, margins also erose or laciniate, apex acute, long-acuminate to cuspidate, or ± truncate, occasionally 2- or 3-fid;

petiole 0.1–6.9(–15.2) cm;

blade ovate to deltate, 1.2–7.7 × 0.8–7.8 cm, base cordate to truncate, margins crenate or crenulate to ± serrulate.

Peduncles

3–25 cm, glabrous or sparsely pubescent.

1–6.1 cm, glabrate to puberulent, sometimes glabrous below bracteoles.

Flowers

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.

sepals lanceolate, margins usually eciliate, auricles 0.5–1.3 mm;

petals white adaxially, upper 2 and lower 3 tinged soft reddish violet abaxially, rarely white on both surfaces, all petals usually with yellow patch basally, lower 3 usually purple-veined, lateral 2 bearded, lowest 5.5–20 mm, spur white, gibbous, 1–2 mm;

style head bearded; cleistogamous flowers axillary or absent.

Capsules

ellipsoid, 5–12 mm, glabrous.

ovoid to ellipsoid, 2.5–10 mm, sometimes muriculate, glabrous or puberulent.

Seeds

beige, mottled to bronze, 1.5–2.5 mm.

brown to dark brown or purplish black, 1.5–2.5 mm.

2n

= 54.

Viola sororia

Viola canadensis

Phenology Flowering Mar–Jun.
Habitat Dry to mesic habitats in woods, thickets, stream banks, moist prairies, pastures, disturbed ground, not in saturated soil
Elevation 0–3000 m (0–9800 ft)
Distribution
from FNA
AL; AR; CO; CT; DC; DE; FL; GA; IA; IL; IN; KS; KY; LA; MA; MD; ME; MI; MN; MO; MS; MT; NC; ND; NE; NH; NJ; NM; NY; OH; OK; PA; RI; SC; SD; TN; TX; UT; VA; VT; WI; WV; BC; MB; NB; NF; NS; ON; PE; QC; SK
[WildflowerSearch map]
[BONAP county map]
from FNA
AK; AL; AR; AZ; CO; CT; GA; IA; ID; IL; IN; KY; MA; MD; ME; MI; MN; MT; NC; ND; NE; NH; NJ; NM; NY; OH; OR; PA; RI; SC; SD; TN; UT; VA; VT; WA; WI; WV; WY; AB; BC; MB; NB; NS; NT; ON; QC; SK; YT
[WildflowerSearch map]
[BONAP county map]
Discussion

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.)

Varieties 3 (3 in the flora).

(Discussion copyrighted by Flora of North America; reprinted with permission.)

Key
1. Rhizomes branched
var. rugulosa
1. Rhizomes not branched
→ 2
2. Plants 11–46 cm; basal leaf blades 2.4–9.2 cm wide.
var. canadensis
2. Plants 3–14(–18) cm; basal leaf blades 0.9–3.8 cm wide.
var. scopulorum
Source FNA vol. 6, p. 158. FNA vol. 6, p. 125.
Parent taxa Violaceae > Viola Violaceae > Viola
Sibling taxa
V. adunca, V. affinis, V. arvensis, V. bakeri, V. beckwithii, V. bicolor, V. biflora, V. blanda, V. brittoniana, V. canadensis, V. canina, V. charlestonensis, V. clauseniana, V. cucullata, V. cuneata, V. douglasii, V. egglestonii, V. epipsila, V. flettii, V. frank-smithii, V. glabella, V. guadalupensis, V. hallii, V. hastata, V. hirsutula, V. howellii, V. japonica, V. labradorica, V. lanceolata, V. langsdorffii, V. lithion, V. lobata, V. macloskeyi, V. missouriensis, V. nephrophylla, V. novae-angliae, V. nuttallii, V. ocellata, V. odorata, V. orbiculata, V. palmata, V. palustris, V. pedata, V. pedatifida, V. pedunculata, V. pinetorum, V. praemorsa, V. primulifolia, V. prionantha, V. pubescens, V. purpurea, V. quercetorum, V. renifolia, V. riviniana, V. rostrata, V. rotundifolia, V. sagittata, V. selkirkii, V. sempervirens, V. septemloba, V. sheltonii, V. striata, V. subsinuata, V. tomentosa, V. tricolor, V. trinervata, V. tripartita, V. umbraticola, V. utahensis, V. vallicola, V. villosa, V. walteri
V. adunca, V. affinis, V. arvensis, V. bakeri, V. beckwithii, V. bicolor, V. biflora, V. blanda, V. brittoniana, V. canina, V. charlestonensis, V. clauseniana, V. cucullata, V. cuneata, V. douglasii, V. egglestonii, V. epipsila, V. flettii, V. frank-smithii, V. glabella, V. guadalupensis, V. hallii, V. hastata, V. hirsutula, V. howellii, V. japonica, V. labradorica, V. lanceolata, V. langsdorffii, V. lithion, V. lobata, V. macloskeyi, V. missouriensis, V. nephrophylla, V. novae-angliae, V. nuttallii, V. ocellata, V. odorata, V. orbiculata, V. palmata, V. palustris, V. pedata, V. pedatifida, V. pedunculata, V. pinetorum, V. praemorsa, V. primulifolia, V. prionantha, V. pubescens, V. purpurea, V. quercetorum, V. renifolia, V. riviniana, V. rostrata, V. rotundifolia, V. sagittata, V. selkirkii, V. sempervirens, V. septemloba, V. sheltonii, V. sororia, V. striata, V. subsinuata, V. tomentosa, V. tricolor, V. trinervata, V. tripartita, V. umbraticola, V. utahensis, V. vallicola, V. villosa, V. walteri
Subordinate taxa
V. canadensis var. canadensis, V. canadensis var. rugulosa, V. canadensis var. scopulorum
Synonyms V. chalcosperma, V. floridana, V. latiuscula, V. palmata var. sororia, V. papilionaceae, V. priceana, V. rosacea, V. septentrionalis, V. wilmattiae
Name authority Willdenow: Hort. Berol. 1: plate 72. (1806) Linnaeus: Sp. Pl. 2: 936. (1753)
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