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enable glossary links

pioneer violet, smooth yellow violet, stream or smooth yellow or yellow wood or wood or smooth yellow woodland violet, stream violet, violette glabre, yellow wood violet

arctic yellow violet, European field pansy, northern violet, queen Charlotte twinflower violet, twinflower violet

Habit Plants perennial, caulescent, not stoloniferous, 3–38 cm. Plants perennial, caulescent, not stoloniferous, 3–20(–25) cm.
Stems

1–3, erect or prostrate, leafless proximally, leafy distally, glabrous or finely puberulent, on caudex from fleshy rhizome.

1–3+, ascending or erect, leafy proximally and distally, glabrous, on caudex from fleshy rhizome.

Leaves

basal and cauline;

basal: 0–4(–7);

stipules ovate to obovate, margins entire, crenate, or serrate, usually glandular, apex acute to obtuse;

petiole 7–27.5 cm, glabrous or puberulent;

blade usually reniform to ovate, sometimes orbiculate, 3.3–8.5 × 2–9.3 cm, base cordate, margins crenate to serrate, ciliate or eciliate, apex acute to obtuse, mucronulate, surfaces glabrous or finely puberulent;

cauline similar to basal except: usually restricted to distal ends of naked stems;

stipules ovate to oblong, margins erose or subserrate, often glandular, apex acute to acuminate;

petiole 0.2–2.9 cm, glabrous or finely puberulent;

blade ovate to deltate, 1.4–5.7 × 0.8–4.7 cm, base cordate to truncate, margins crenate to ± serrate, ciliate (sometimes limited to proximal half), apex acute.

basal and cauline;

basal: 2–3(–4);

stipules ovate-lanceolate, ovate, or oblong, margins entire, apex ± acute;

petiole 1.5–15 cm, glabrous;

blade broadly reniform to orbiculate, 0.5–4.6 × 0.9–6.4 cm, base cordate, margins crenate to crenate-serrate, ciliate, apex obtuse, rounded, or truncate, rarely with terminal point, abaxial surface sparsely puberulent on veins, adaxial surface glabrate to ± densely puberulent;

cauline similar to basal except: stipules lanceolate, ovate, or oblong, margins entire to erose, apex acute to obtuse;

petiole 0.3–7(–10) cm;

blade sometimes ovate, 0.8–3.7 × 1–4.8 cm.

Peduncles

2–8 cm, glabrous or pubescent.

2–9 cm, usually glabrous.

Flowers

sepals linear-lanceolate, margins eciliate, auricles 0.5–1 mm;

petals deep lemon-yellow on both surfaces, lower 3 and sometimes upper 2 brownish purple-veined, lateral 2 bearded, lowest 6–18 mm, spur yellow to greenish, gibbous, 0.5–2 mm;

style head bearded; cleistogamous flowers axillary.

sepals with or without purple stripe on both sides of midvein, narrowly lanceolate to oblong, margins ciliate or eciliate, auricles 0.5–1 mm;

petals deep lemon-yellow on both surfaces, lower 3 and often upper 2 brownish purple-veined, lateral 2 beardless, lowest 6–15 mm, spur yellow to yellowish green, gibbous, 2–2.5 mm;

style head beardless; cleistogamous flowers axillary.

Capsules

ovoid to ellipsoid, 7–13 mm, glabrous.

oblong-ovoid, 3–6 mm, glabrous or sparsely pubescent.

Seeds

light to dark brown, shiny, 2–2.2 mm.

purple, sometimes streaked with light and dark brown, 1.5–2.5 mm.

2n

= 24.

Viola glabella

Viola biflora

Phenology Flowering Mar–Aug.
Habitat Damp, wet, or shady places in forests, stream banks
Elevation 0–2600 m (0–8500 ft)
Distribution
from FNA
AK; CA; ID; MT; OR; WA; AB; BC; Asia
[WildflowerSearch map]
[BONAP county map]
from FNA
AK; CO; BC; YT; Europe; Asia
[WildflowerSearch map]
[BONAP county map]
Discussion

Viola glabella is similar in overall appearance to V. pubescens. The cauline leaves are sometimes described as appearing only near the apex of the stem (P. A. Munz 1959), but often a leaf occurs from a node on the stem below the apex.

Viola californica was described from collections made in Humboldt and Trinity counties, California, and may have arisen as a hybrid between V. glabella and V. lobata var. integrifolia. It is apparently limited to Abies concolor forests above 1520 m (M. S. Baker 1953). Study of V. californica is needed to determine if taxonomic recognition is warranted.

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

Varieties 5 (2 in the flora).

Viola biflora may be the most widely distributed species of the genus in the Northern Hemisphere. Although occurring most often in mountainous areas at high elevations, it is known from Alaska near the coast at elevations of ca. 45 m (PNW Herbaria Portal 2010) and has been reported from lowland meadows in Kamchatka (V. B. Baird 1942), and is occasionally found near sea level in exposed rocky habitats on the west coast of the Queen Charlotte Islands (R. A. Calder and R. L. Taylor 1968).

Sometimes described as high latitude, circumpolar, Viola biflora also occurs in mid latitudes north of the equator. It is not truly circumpolar; it does not occur in eastern Canada or in Greenland. The deeply cleft style head sets V. biflora apart from all other species in North America. V. B. Baird (1942) suggested that the occasional presence of two cleistogamous flowers in the axil of the same leaf may account for the name “biflora.”

H. N. Ridley (1930) said that in Europe, deer (Cervus dama Linnaeus and Rangifer tarandus Linnaeus) may play a role in the dispersal of Viola biflora; seeds have been recovered from their droppings.

Nonflowering Viola biflora can be confused with V. renifolia where their ranges overlap in Yukon, Alaska, and Colorado.

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

Key
1. Lowest petal 6–10 mm; seeds 1.5–2 mm; sepals usually without purple stripe; Yukon, Alaska, Colorado.
var. biflora
1. Lowest petal 11–15 mm; seeds 2.5 mm; sepals usually with purple stripe; Queen Charlotte Islands, Vancouver Island, British Columbia.
var. carlottae
Source FNA vol. 6, p. 131. FNA vol. 6, p. 123.
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. 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
V. adunca, V. affinis, V. arvensis, V. bakeri, V. beckwithii, V. bicolor, 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. 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. biflora var. biflora, V. biflora var. carlottae
Synonyms V. californica, V. canadensis var. sitchensis, V. glabella var. remotifolia Chrysion biflorum
Name authority Nuttall: in J. Torrey and A. Gray, Fl. N. Amer. 1: 142. (1838) Linnaeus: Sp. Pl. 2: 936. (1753)
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