Bird’s-foot violet (Viola pedata) of the Violet (Violaceae) family, the paragon of the violets, has distinctive leaves and large, exquisite flowers in several colors. The genus name is the classical Latin name for violets. The specific epithet, the Latin for “foot-like,” refers to leaf shape. In the U.S., bird’s-foot violet occurs in two broad belts: 1) from southeast Texas and Louisiana north to the Great Lakes region and 2) from Mississippi to Kentucky east to the Atlantic coast and thence northeast into southern New England. In Arkansas, it occurs statewide except for the lowlands within the West Gulf Coastal Plain and the Mississippi Alluvial Plain. Habitat preference is sunny sites with well-drained, sandy to rocky, acid soils of upland woods, prairies and roadside slopes.
Plants have a vertically oriented, stubby, whitish rootstock with a few white ropy roots toward the base. The rootstock has a crown, positioned at or just above the soil surface, from which leaves and flowers emerge, but never stems. Plants are acaulescent––stemless. As leaves and flowers develop and fall off year by year, elongated horizontal petiole and flower stalk scars remain from fallen leaves and flowers. As the plant ages, the diameter of the crown increases so that the rootstock tends to become conical. Lacking rhizomes, clonal colonies do not form.
Bird’s-foot violet may have a dozen or more deeply, palmately dissected basal leaves. New palmate outer leaves with spatula-shaped lobes (“spatulate leaves” herein) develop in fall and persist through winter––plants are evergreen––while new inner leaves with linear lobes (“bird’s-foot leaves” herein) develop in mid- to late winter and persist through the growing season. As the new spatulate leaves develop, any remaining bird’s-foot leaves fade away. Along with the palmate leaves, small variously shaped leaves appear in fall in advance of the spatulate leaves.
The palmate leaves typically have 3 main lobes with an undivided central lobe and 2 lateral lobes divided into 3-5 lobes. Lobes of spatulate leaves are elongate with rounded apices that may be in turn slightly lobed to deeply incised. Lobe margins are stiff, entire and upturned, with pinnate venation. Short fine hairs may occur on the adaxial leaf surface (pubescence puberulent) and along margins (margins ciliate). The bird’s-foot leaves have a smooth margin with an occasional tooth. Blades of the spatulate leaves continue as narrow wings down the full-length of the petiole, whereas petioles of the bird’s-foot leaves are not winged. Spatulate leaves remain close to the ground from fall into spring; the later-arriving bird’s-foot leaves are at first ascending before reclining. As plants achieve bloom and beyond, the bird’s foot leaves mostly hide the spatulate leaves, which apparently decline through the summer. When in bloom, a plant may be 4 inches tall.
Leaves have slender weak petioles. The glaucous petioles, rounded below and grooved above, are typically a pale green but may be reddish. A weak pair of hidden lanceolate stipules, with ragged margins, occurs at the base of the petioles. Petioles of the bird’s-foot leaves continue to grow during and after flowering so that final leaf length may be 7+ inches. As these petioles recline, plant height remains to about 4 inches.
Flowers bloom primarily in March and April. The single flowers, arising directly from the rootstock crown, are borne on glaucous stalks, which bear an opposite pair of bracts. The slender, weak flower stalks continue to lengthen through the growing season. Early flowers are positioned at leaf-level, but later flowers are above the reclining bird’s-foot leaves. Unlike the weedy common blue violet, bird’s-foot violet does not produce cleistogamous flowers (producing seed without fertilization).
In bud, flowers are bent downward, but in bloom face forward or upward. Across their somewhat flattened face, they measure ¾ to 1+ inch. The calyx comprises 5 lanceolate, pale green, finely ciliate sepals about ½ inch long. Prominent auricles (ear-like lobes) extend down from their base.
The corolla comprises 5 petals: an upper pair of overlapping, back-flared petals, two lateral petals, and a larger central lip petal below. The upper pair are oval with a short base; the laterals are spurred at the base; and the lower petal twists backwards to form an elongate nectar spur with a rounded tip. Petals may be all blue to lavender (considered the “standard” color), bi-color with 3 blue to lavender lower petals and 2 upper purple petals, or rarely, all white. The lower central petal, when blue to lavender, is white at the base with prominent purple veins (nectar guides). (White flowers do not have highlighted veins.) Again unlike the common blue violet or the prairie violet, all the petals are beardless (without hairs).
Flowers have 5 stamens and a single, 3-carpellate pistil. The stubby stamens have pale yellowish green filaments tipped with flattened orange oval anthers. Stamens fit tightly around the pistil. The stubby glabrous pistil consists of a shiny pale green ovary and a post-like, whitish green, clavate (thickened at distal end) style. At anthesis, only the tip of the style is exposed beyond the anthers, with the tiny protruding stigma almost unnoticeable.
Ovaries of fertilized flowers develop into ellipsoid, glabrous capsules with 3 parietal placentas, each placenta indicating where 2 of the 3 carpels have merged. The 50 or so seeds become copper-colored when dry. For dispersal, exploding capsules can eject seeds a short distance, and, with a gel packet at the seed base, seeds can be dispersed by feeding ants.
In a garden, rock garden or natural area, bird’s-foot violet would be an ideal plant for a fairly sunny, well-drained, sandy to rocky site with minimal competition. With its distinctive foliage, large flowers with several color varieties, and lack of cleistogamous flowers, many gardeners consider bird’s-foot violet to be their favorite violet.
In addition to bird’s-foot violet, at least 14 other species in the genus occur in Arkansas. Of these species, prairie violet (aka crow’s-foot violet, Viola pedatifida) has similarly finely dissected, palmately lobed leaves. The two species are easy to distinguish at the time of bloom: flowers of prairie violet are smaller and the lateral and basal petals are bearded. Prairie violet is a species of conservation concern in Arkansas, at the southern edge of its range, having been documented in a few tallgrass prairie remnants in only a couple of northwestern counties.
Article and photographs by ANPS member Sid Vogelpohl