Perennial herb 20 - 40 cm tall Stem
: erect, hairless or minutely hairy with both leaves and flowers, and arising from a creeping rhizome. Leaves
: both basal and alternate, long-stalked, heart-shaped (upper leaves often longer than wide), 5 - 10 cm long, and variously toothed. The stipules, which sometimes fall off early, are white, thin and papery, about 1 cm long, non-toothed, and narrowly lance-shaped with a long pointed tip. Flowers
: in upper leaf axils, long-stalked, white with yellow centers (often purplish on outside), about 1.5 cm long, bilaterally symmetric with two upper petals, two lateral petals, and lower petal with base modified into a rounded nectar spur. In the summer, producing very fertile flowers that do not open (cleistogamous). Sepals
: five, green, lance-shaped with ear-like appendages (auricles) at the base. Petals
: five, separate, all differently shaped, white with yellow base, tinged purplish on outside, and lower three with purplish lines toward base. The two lateral petals have a beard of hairs near the base, and the lowest petal is prolonged at its base into a short, rounded spur or sac. Stamens
: five, separate, but very tightly arranged so anthers touch as they surround ovary. The filaments are very short, and the lower two stamens have spur-like nectaries on their backs that extend into the spur or sac of the lower petal. Pistil
: with a single-chambered, superior ovary; a single bearded style that enlarges near the tip; and a head-shaped stigma. Fruit
: a many-seeded, ellipsoid to globular capsule that opens lengthwise from top. The seeds have a large amount of oily endosperm, and often an appendage (aril).
Similar species: Viola canadensis is probably most often confused with V. striata, but that species has creamy-white flowers with fringed sepals, and green stipules with heavy fringe along the edges. Also similar is V. pubescens (and its two varieties), but that species has solid yellow flowers, more egg-shaped stipules that are green and herbaceous, and the stem leaves are usually wider than long. This is the only truly white-flowered species of Viola in the Chicago Region (versus creamy white) that has both leaves and flowers along the stem. While most species of Viola that have purplish flowers can produce albino (all white) flowers, they can be distinguished by not having evident stems, and the stipules having fringe or deep lobes.
Flowering: April to June
Habitat and ecology: Not common, mostly in the eastern parts of the Chicago Region in mesic sugar maple woods, especially preferring more neutral or alkaline soils.
Occurence in the Chicago region: native
Notes: This species can be quite variable throughout its range in characteristics of hairiness, size of the rootstalk or rhizomes, shape of the leaves, and number of stems per plant. Some authorities split the species into two varieties (the typical variety, and V. canadensis var. rugulosa), but we follow the treatment of Ballard 1994.
Etymology: Viola is the classical name for the genus. Canadensis means "of (or from) Canada and North America".
Author: The Field Museum