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Howell's violet, violette de Howell

alpine violet, American dog or Labrador or alpine violet, American dog violet, dog violet, Labrador violet, violette du Labrador

Habit Plants perennial, caulescent, not stoloniferous, 2–44 cm. Plants perennial, caulescent, not stoloniferous, 5–20 cm.
Stems

1–4, ascending to erect (sometimes later reclining to nearly prostrate), glabrous or sparsely pubescent, on caudex from subligneous rhizome.

1–5, erect (later reclining), glabrous, on caudex from subligneous rhizome.

Leaves

basal and cauline;

basal: 1–6;

stipules linear-lanceolate to oblong, margins mostly entire or laciniate with gland-tipped projections, apex acute to acuminate;

petiole 4–15 cm, glabrous or sparsely puberulent;

blade ovate to reniform, 1.9–6.8 × 2.1–6.4 cm, thin, base cordate, margins crenate, ciliate, apex acute to usually obtuse, surfaces glabrous or sparsely puberulent;

cauline similar to basal except: stipules linear-lanceolate or deltate to oblong, apex acute or long-acuminate;

petiole 1–4.5 cm;

blade 2–5.1 × 1.2–5.8 cm.

basal and cauline;

basal: 1–5;

stipules mostly lanceolate-linear, margins usually laciniate with gland-tipped projections, apex acute;

petiole 1–9.5 cm, glabrous or puberulent;

blade reniform or ovate to deltate, 1.4–5.5 × 1.8–5.3 cm, base cordate, not decurrent on petiole, margins crenate or serrate, mostly eciliate, apex acute to obtuse, surfaces usually glabrous, sometimes pubescent adaxially near margin;

cauline similar to basal except: stipules lanceolate to ovate, margins ± entire or laciniate, projections often gland-tipped, apex acuminate;

petiole 0.5–3.6 cm, glabrous;

blade narrowly ovate to orbiculate, 1.8–2.9 × 1.5–3.1 cm, base deeply cordate to truncate, margins regularly crenate, apex obtuse to broadly rounded or apiculate.

Peduncles

2.8–17.8 cm, glabrous or sparsely pubescent.

5–9 cm, glabrous or pubescent.

Flowers

sepals lanceolate, margins ciliate or eciliate, auricles 1–2 mm;

petals violet to soft blue-violet on both surfaces, whitish basally, lower 3 dark violet-veined, lateral 2 densely bearded, lowest 14–23 mm, spur blue-violet to whitish, gibbous to elongated, 2.4–5 mm, usually less than 1/2 lowest petal, tip straight;

style head bearded; cleistogamous flowers axillary.

sepals lanceolate, margins ciliate or eciliate, auricles not enlarged in fruit, 1–1.5 mm;

petals usually lavender-violet to violet on both surfaces, rarely white, lower 3 white basally, darker violet-veined, lateral 2 sparsely bearded, lowest 9–16 mm, spur white to pinkish violet, elongated, 4–8 mm, tip usually straight, sometimes curved up;

style head beardless; cleistogamous flowers unknown.

Capsules

ellipsoid, 7–11 mm, glabrous.

ovoid to ellipsoid, 5–7 mm, glabrous.

Seeds

light brown, 2.1–2.8 mm.

beige to bronze, 1.5–2 mm.

2n

= 40, 80.

= 20.

Viola howellii

Viola labradorica

Phenology Flowering Apr–Jul. Flowering Apr–Aug.
Habitat Moist, shady areas, coniferous forests, prairies, along streams Rich, mesic to wet woods, swamps, bogs
Elevation 50–1500 m (200–4900 ft) 50–3000 m (200–9800 ft)
Distribution
from FNA
CA; OR; WA; BC
[WildflowerSearch map]
[BONAP county map]
from FNA
AL; CO; CT; DC; DE; GA; IL; IN; KY; MA; MD; ME; MI; MN; NC; ND; NH; NJ; NY; OH; PA; RI; SC; TN; VA; VT; WI; WV; MB; NB; NL; NS; NT; ON; PE; QC; SK; SPM; Greenland
[WildflowerSearch map]
[BONAP county map]
Discussion

Viola howellii is similar to V. adunca and usually occupies moister habitats along the western side of the Cascade Mountains (H. E. Ballard 1992). The first documented record of this species in California was recently reported from Siskiyou County (R. J. Little 2010).

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

H. E. Ballard (1994) made a compelling case for including Viola conspersa within V. labradorica, which is followed here. Ballard (1992) did not recognize V. labradorica as occurring in Colorado. Several western herbaria have collections identified as V. labradorica (ASC, CS, KHD, RM, RMBL; http://swbiodiversity.org/seinet/index.pho). Labels on some collections at KHD imply that V. labradorica is considered synonymous with V. adunca var. bellidifolia.

Viola labradorica reportedly hybridizes with V. adunca, V. rostrata (= V. ×malteana House), and V. striata (= V. ×eclipes H. E. Ballard), and less frequently with V. walteri var. appalachiensis and var. walteri.

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

Source FNA vol. 6, p. 134. FNA vol. 6, p. 135.
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. 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. 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. 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
Synonyms V. adunca var. minor, V. canina var. muhlenbergii, V. conspersa, V. leucopetala, V. muhlenbergiana, V. muhlenbergiana var. minor, V. muhlenbergii
Name authority A. Gray: Proc. Amer. Acad. Arts 22: 308. (1887) Schrank: Denkschr. Kõnigl.-Baier. Bot. Ges. Regensburg 1(2): 12. (1818)
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