Viola species - Violets and Pansies

This genus is divided into violets and pansies. The main difference is small leaf-like structures called stipules, that are found at the base of the leaves where they emerge from the stems. In violets the stipules are toothed, in pansies they have lobes and are much more leaf-like, indeed in the field stipules and leaves can easily be confused in pansies, see the annotated photograph.

In both violets and especially pansies, colour is not reliable for identification. White violets and yellow, white or purple pansies are common..

There are three species of pansy in Lanarkshire and the habitat is useful in distinguishing them see the notes on the pictures.

Viola arvensis  - Field Pansy Sprawling habit. Small white / cream cup-shaped flowers 8-20mm vertically. Sepals exceed the petals and sepal appendage can be up to 1/3 the length of the sepal. Stipules pinnasect, lobed and mid lobe is leaf-like and ±crenate. A plant of waste ground, field margins and roadsides

Viola lutea  - Mountain Pansy Perennial. Corolla > 20mm vertically, with barely overlapping petals. Usually yellow, can be blue, purple or blotched. Often in Renfrewshire and Lanarkshire it is all purple with a yellow throat. usually a singly flower. Terminal segment of the stipules scarcely wider than the others and entire. Has slender rhizomes. Usually several stems from ground level. Tends to be upland areas.

Viola tricolor  - Wild Pansy very variable! Much branched, usually 2 or more flowers per stem. Flowers can be any mixture of sky blue, violet, yellow, and cream. Corolla 10 - 25mm vertically. Sepals shorter than the petals, triangular with a variable appendage. Stipules palmately lobed and the central segment wider than the others and maybe ±crenate or entire.

There are two common species of violet in Lanarkshire, one in dry ground and the other in wet ground.

Viola palustris  - Marsh Violet Leaves are round or kidney shaped leaves with a cordate base, faintly toothed and glabrous. Flowers pale lilac with conspicuously veined lower petal. Flowers and leaves arise on individual stalks from the underground rhizome.

Viola riviniana  - Common Dog-violet Basal leaf rosette; leaves ≤1.3x long as wide, perennial with leafy stems. Basal rosette ovate to orbicular, obtuse and deeply cordate.

Capsules, petioles and lower side of leaves hairless ± few hairs on upper surface of leaves especially on veins.

Sepals acute, appendages > 1.5mm. Corolla spur is paler than the corolla which is pale blue / violet with a vertical notch at the end. Petals much branched veins on the lower petal.

Viola canina- Dog Violet is uncommon. ±Glabrous perennial with leafy stems and no basal rosette. Leaves are ovate to narrowly ovate (> 1.4 as long as wide). Flower blue-grey with a whitish-yellow spur.

Viola odorata Sweet Violet is also uncommon. Perennial with leaves and flowers from a central tuft, no basal rosette, stolons present and spreads in patches. Leaves (both sides) and petioles hairy are shiny dark green.

Hairs on petioles <0.3mm reflexed or appressed. Leaves ovate to ovate-orbicular, deeply cordate.

Sepals blunt. ± Sweet smelling flowers violet or whitish with spur of the same colour. Flowers can be pinkish, not blue.