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Howell's violet, violette de Howell

three-part or Piedmont or threepart violet, threepart violet

Habit Plants perennial, caulescent, not stoloniferous, 2–44 cm. Plants perennial, caulescent, not stoloniferous, 10–40 cm.
Stems

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

1(2), 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);

stipules ovate, not leaflike, margins entire, apex acute to acuminate, surfaces glabrous or puberulent;

petiole 9–11.5 cm, glabrous or puberulent;

blade unlobed, ovate, or 3–5-lobed, 4–5 × 1–5 cm, base cordate, margins entire or crenate-serrate, ciliate or eciliate, apex acute, surfaces glabrous or ± puberulent;

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

stipules ovate to oblong;

petiole 0.7–7.2 cm, glabrous or puberulent;

blade unlobed, ovate or deltate, or 3-lobed (if 3-lobed, lateral lobes falcate, middle rhombic, longer than others, lobes may appear petiolate; unlobed and 3-lobed leaves can occur on same plant), 1–6 × 0.5–5.5 cm, base truncate to cuneate, margins serrate, ciliate or eciliate, surfaces glabrous or pubescent.

Peduncles

2.8–17.8 cm, glabrous or sparsely pubescent.

1.5–4 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 to ovate, margins ciliate or eciliate, auricles 0.1–0.5 mm;

petals lemon-yellow adaxially, upper 2, rarely others, brownish purple abaxially, lowest and usually lateral 2 brownish purple-veined, lateral 2 and sometimes lowest bearded, lowest 10–18 mm, spur yellow, gibbous, 0.5–2 mm;

style head bearded; cleistogamous flowers axillary.

Capsules

ellipsoid, 7–11 mm, glabrous.

ovoid to ellipsoid, 9–12 mm, glabrous.

Seeds

light brown, 2.1–2.8 mm.

beige, bronze, or brown, 2.4–3 mm.

2n

= 40, 80.

= 12.

Viola howellii

Viola tripartita

Phenology Flowering Apr–Jul. Flowering Mar–May.
Habitat Moist, shady areas, coniferous forests, prairies, along streams Rich woods
Elevation 50–1500 m (200–4900 ft) 50–1600 m (200–5200 ft)
Distribution
from FNA
CA; OR; WA; BC
[WildflowerSearch map]
[BONAP county map]
from FNA
AL; FL; GA; KY; MS; NC; OH; PA; SC; TN; VA; WV
[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.)

Some authors recognize two varieties of Viola tripartita based on lobed versus unlobed leaves. F. L. Lévesque and P. M. Dansereau (1966) suggested that leaf variation is the only character difference between vars. tripartita and glaberrima. N. H. Russell (1965) stated that V. tripartita plants with lobed and unlobed leaves are sympatric and frequently intergrade and did not recognize them as distinct. The situation with two leaf forms in V. tripartita is similar to V. lobata, which also has two leaf forms.

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

Source FNA vol. 6, p. 134. FNA vol. 6, p. 161.
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. 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. umbraticola, V. utahensis, V. vallicola, V. villosa, V. walteri
Synonyms V. hastata var. glaberrima, V. hastata var. tripartita, V. tripartita var. glaberrima
Name authority A. Gray: Proc. Amer. Acad. Arts 22: 308. (1887) Elliott: Sketch Bot. S. Carolina 1: 302. (1817)
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