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Howell's violet, violette de Howell

moose horn violet, pine violet, yellow wood violet

Habit Plants perennial, caulescent, not stoloniferous, 2–44 cm. Plants perennial, caulescent, not stoloniferous, 5–46 cm.
Stems

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

1–3, erect, leafless proximally, leafy distally, glabrous or puberulent, 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: 0–2, unlobed or palmately 3–11-lobed;

stipules ovate to lanceolate, margins ± entire or serrate, apex acute;

petiole 5–27 cm, glabrous or puberulent;

blade sometimes glaucous, deltate to reniform, 3.5–8.5 × 4.5–13.5 cm, base cordate, truncate, or attenuate, margins on unlobed leaves coarsely dentate-serrate, margins on lobed leaves usually entire, sometimes few-toothed, ciliate (sometimes only proximal 1/2) or eciliate, apex acute to obtuse, mucronulate, surfaces glabrous or puberulent;

cauline similar to basal except: distal on naked stems, unlobed and divided leaves can occur on same plant, if divided, palmately 3–12-lobed;

stipules sometimes large and ± leaflike, margins entire, lacerate, or laciniate, sometimes with gland-tipped projections, apex acute to acuminate;

petiole 0.2–8.8 cm;

blade reniform to reniform-cordate, ± ovate, deltate, or rhombic, 1.5–5.5 × 1.4–10 cm, base cordate, subcordate, truncate, or attenuate, margins entire, crenate-serrate, or dentate, or coarsely lacerate to deeply serrate, often entire distally, ciliate or rarely eciliate, apex acute to obtuse, often long-tapered, mucronulate.

Peduncles

2.8–17.8 cm, glabrous or sparsely pubescent.

2–13 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 0.1–1 mm;

petals deep lemon-yellow adaxially, usually upper 2 and sometimes lateral 2 brownish purple abaxially, lower 3 and sometimes upper 2 brownish purple-veined basally, lateral 2 bearded, lowest 8–19 mm, spur yellow to greenish, gibbous, 0.5–2 mm;

style head bearded; cleistogamous flowers axillary.

Capsules

ellipsoid, 7–11 mm, glabrous.

ellipsoid-ovoid, 6–16 mm, glabrous.

Seeds

light brown, 2.1–2.8 mm.

light brown, blotched or streaked with brown, shiny, 2.1–2.7 mm.

2n

= 40, 80.

= 12.

Viola howellii

Viola lobata

Phenology Flowering Apr–Jul.
Habitat Moist, shady areas, coniferous forests, prairies, along streams
Elevation 50–1500 m (200–4900 ft)
Distribution
from FNA
CA; OR; WA; BC
[WildflowerSearch map]
[BONAP county map]
from FNA
CA; OR; nw Mexico
[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.)

Varieties 2 (2 in the flora).

V. B. Baird (1942) noted that Viola lobata was more closely related to V. tripartita than to any western Viola.

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

Key
1. Cauline leaf blades usually deeply divided, seldom unlobed, reniform, ± ovate, or deltate, if divided, palmately 3–12-lobed, lobe margins usually entire.
var. lobata
1. Cauline leaf blades unlobed, deltate to rhombic, ovate, or reniform-cordate, margins ± serrate, crenate-serrate, or dentate to deeply serrate or coarsely lacerate, often entire distally.
var. integrifolia
Source FNA vol. 6, p. 134. FNA vol. 6, p. 137.
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. labradorica, V. lanceolata, V. langsdorffii, V. lithion, 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. lobata var. integrifolia, V. lobata var. lobata
Name authority A. Gray: Proc. Amer. Acad. Arts 22: 308. (1887) Bentham: Pl. Hartw., 298. (1849)
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