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evergreen violet, redwood violet, redwoods violet, trailing yellow violet, violette toujours verte

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

Habit Plants perennial, caulescent, stoloniferous, 10–30 cm; stolons green or reddish, leafy, sometimes rooting at nodes, becoming lignified in age. Plants perennial, caulescent, not stoloniferous, 3–20(–25) cm.
Stems

1–5, prostrate, spreading, glabrous or sparsely puberulent, from current and/or previous year’s growth, on usually vertical, fleshy rhizome, rooting and forming rosettes at or near tip; rooted rosettes often develop into an erect, fleshy caudex from which new stems are produced.

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

Leaves

evergreen, basal and cauline;

basal: 1–6(–10);

stipules deltate to ovate or linear-lanceolate, margins entire or glandular-toothed, apex acute to long-acuminate;

petiole 2–16 cm, glabrous;

blade often purple-spotted abaxially and/or adaxially, orbiculate to ovate, 1–4.5 × 2–3.9 cm, base cordate to truncate, margins crenate, eciliate, apex blunt to obtuse, mucronulate, surfaces glabrous or with scattered bristles on one or both surfaces;

cauline similar to basal except: stipules deltate to lanceolate, margins entire or sparingly toothed;

petiole 0.3–3 cm;

blade 1.2–2.2 × 1.2–2 cm.

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

5–10 cm, glabrous.

2–9 cm, usually glabrous.

Flowers

sepals lanceolate to ovate-lanceolate, margins eciliate, auricles 1–2 mm;

petals lemon-yellow on both surfaces, lower 3 and sometimes upper 2 brownish purple-veined, lateral 2 bearded, lowest 8–17 mm, spur yellow or whitish, gibbous, 1–2.5 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

mottled with purple, spherical to ovoid, 5–8 mm, glabrous.

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

Seeds

brown, tinged purple, 2–2.5 mm.

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

2n

= 24, 48.

Viola sempervirens

Viola biflora

Phenology Flowering Jan–Jul.
Habitat Redwood forests, other coastal forests, Douglas fir, other coniferous forests
Elevation 30–1400 m (100–4600 ft)
Distribution
from FNA
AK; CA; ID; OR; WA; BC
[WildflowerSearch map]
[BONAP county map]
from FNA
AK; CO; BC; YT; Europe; Asia
[WildflowerSearch map]
[BONAP county map]
Discussion

In California, Viola sempervirens occurs in shaded redwood forests and other coastal forest habitats. In Oregon and Washington, it occurs in Douglas fir and other coniferous forests, where it can form mats (clones) one meter or more in diameter; its prostrate, spreading growth habit is similar to V. walteri. The leafy stems of V. sempervirens are similar to the leafy stolons of V. odorata.

(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. 157. 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. 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. 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. sarmentosa, V. sempervirens subsp. orbiculoides Chrysion biflorum
Name authority Greene: Pittonia 4: 8. (1899) Linnaeus: Sp. Pl. 2: 936. (1753)
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