The Lady Slipper newsletter of the Kentucky Native Plant Society has been published since the Society’s founding in 1986. We occasionally feature an article from a past issue. Wildflower Weekend 2025 will be at Carter Caves State Resort Park. Carter county is a hot spot of Violet (Viola) diversity in Kentucky, with 13 species of Viola found in the county. This article, from November 1992, is an in-depth look at the Violas of Kentucky. This article first appeared in Nov 1992, Vol. 7, No. 4. If you would like to see other past issues, visit the Lady Slipper Archives, where all issues from Vol. 1, No. 1, February 1986 to Vol. 39, 2024, can be found.
The Genus Viola (Violaceae) The Violets
by Landon McKinney, KSNPC
There are approximately 40 to 50 species of wild violets occurring throughout North America. Of these, twenty-two species and several varieties occur in Kentucky. Virtually every wildflower enthusiast knows a violet when he or she sees one. Beyond that, distinctions between the various species become quite confusing on occasion, even for the seasoned professional.
Amateur botanists and wildflower enthusiasts alike may assume that the classification of these pretty, little herbs is complete and that there is no question as to what constitutes a species and what does not. However, this belief could not be further from the truth. The violets are considered by many professional botanists to be one of the most difficult groups of plants to work with when producing a floristic treatment.
This problem is certainly not unique to the violets, as many other groups of plants are known to be problematic. We all have had difficulties in identifying a particular plant at one time or another. The wild fact is that the science of taxonomy (the classification of organisms into like groups) is not an absolute science.
Why are the violets so problematic? Well, there are several reasons. One reason is that many species exhibit a wide range of variability in their supposedly definitive characteristics. For example, you find a particular violet and proceed to identify it based on the manual or wildflower guide that you are using. After making a tentative identification, you notice that the description says that the leaves are pubescent (hairy) but as you look at your violet, you see no hairs. Could this be another species, maybe one that is not included in the manual that you are using? Possibly, but a likelier explanation is that you just happened upon a particular plant that is exhibiting an extreme end to a natural range of variation, and that sometimes, this particular individual has few or even no hairs on its leaves. Another reason is that most species, when in close proximity to each other, hybridize freely, and the hybrids produced may be quite fertile.
Now that I have muddied up the water so to speak, let me attempt to make the identification of violets as simple as humanly possible. First, the violets may be divided based on whether they are stemless or stemmed (see figures 3 and 4). The stemless violets have all petioled leaf blades appearing from the base of the plant. The stemmed violets have aerial stems from which petioled leaf blades appear (several species will also produce leaf blades rising from the plant’s base). Second, they may be further divided as to flower color and this gives us the following broad categories:
- wild pansies
- stemmed blue violets
- stemless blue violets
- stemmed yellow violets
- stemless yellow violets
- stemmed white violets
- stemless white violets
The wild pansies consist of two species (Viola rafinesquii and Viola arvensis). They normally occur in yards or in cultivated fields. Their flowers are quite pansy-like except that they are much smaller. They are quite similar to the garden variety called Johnny-jump-up (Viola tricolor).
The stemmed blue violets consist of three species including the long-spurred violet (Viola rostrata), the american dog violet (Viola conspersa), and Walter’s violet (Viola walteri). While infrequent, the first two may be found in rich, mesic, wooded situations throughout the eastern portion of the state while Walter’s violet is considered rare and only known from Jessamine, Fayette, and Carter counties. This violet prefers a limestone substrate and, due to its low-growing or decumbent habit, it is easily overlooked.
The stemless blue violets are probably the best known while also being the most problematic of the violets. The common blue violet (Viola sororia) is highly adaptable to a variety of habitats and we have seen several forms that adapt very well to our lawns and gardens. One of the most striking of these is the confederate violet with its grayish-blue flowers. Other stemless blue violets include the tri-lobed blue violet (Viola palmata), the arrow-leaved violet (Viola sagittata var. saggitata), the ovate- leaved violet (Viola sagittata var. ovata), the marsh blue violet (Viola cucullata), the southern wood violet (Viola hirsutula), Eggleston’s violet (Viola septemloba var. egglestonii), the Missouri blue violet (Viola sororia var. missouriensis), and the ever popular birdsfoot violet (Viola pedata). There are numerous other names of species that may be found in various manuals; however, these are either not found in the state or are now considered as minor variations of one of the above species.
The stemmed yellow violets include one of our most common woodland species, the smooth yellow violet (Viola pubescens var. eriocarpa). One unique characteristic of the smooth yellow violet is the fact that, after flowering, the seed capsules are either woolly or glabrous (hairless). I have never seen this character mixed in any one population as each population appears to have plants of one kind or the other. Nor have I ever been able to figure out, based on other characteristics such as habitat, which capsule type any given population will have. Another stemmed yellow violet considered rare in Kentucky is Viola tripartita, a woodland species known only from several counties in the eastern portion of the state. One of our prettiest violets is the halberd- leaved yellow violet (Viola hastata). While not always the case, the often mottled appearance of the leaf blades adds to the striking appearance of this species. It, too, is confined to rich, wooded situations in the eastern portion of the state.
We have only one stemless yellow violet. The round-leaved yellow violet (Viola rotundifolia) is confined to the eastern portion of the state and is our earliest blooming species. Its thick, leathery, rotund leaves lay prostrate on the ground and may be found in rich, wooded situations.
The stemmed white violets consist of two species, the Canada violet (Viola canadensis) confined to rich, wooded situations in the eastern half of the state, and the white violet (Viola striata), one of our more common species which seems to prefer alluvial or floodplain forests throughout the state. Although white flowered, Viola striata is more closely related to the stemmed blue violets than it is to the Canada violet.
The stemless white violets consist of three easily distinguished species such as the lance-leaved violet (Viola lanceolata) and primrose-leaved violet (Viola primulifolia), both of which love bogs, marshes, and wet meadow situations. The sweet white violet (Viola blanda), loves cool, moist, wooded situations and is mainly confined to the eastern portion of the state.
While being somewhat brief, I hope I have provided a greater understanding and a deeper appreciation for these lovely little herbs. The violets have a long history of use by man, especially in Europe. They are widely grown as ornamentals and our wild violets are used in a variety of ways as food. The leaves may be eaten raw and make an excellent nutritional addition to any fresh garden salad. The flowers may be candied for another delightful treat. Overall, the violets are quite an interesting group of plants and well deserve our attention and appreciation. Come next spring, take a closer look at these little herbs, appreciate their color, intrigue yourself with their subtle differences, and just enjoy. By the way, if you would like to see more than half of the above species in one day, plan a trip to Natural Bridge State Park next spring and walk the Rock Garden and Hood’s Branch trails. While these trails provide one of the best overall spring floral displays in the state, they also provide the only place that I know to see this many species of violets in such a short period of time.