An important detail with violets is whether or not the stems are leafy or the leaves are all basal. The hairs look club-shaped so V. cucullata is a good candidate provided all of the leaves are basal.

Lycopus, thanks for your reponse. It appears that all of the leaves are basal.

I emailed a separate enquiry to a local botanist. He said that the blue violets were difficult, without a specimen in hand, because they're so variable. Although USDA does list V. cucullata as present in Arkansas, the Arkansas Vascular Floral Committee does not recognize it on their list of Arkansas taxa. That botanist thought that V. sororia was a possibility. However, the references I've found mostly agree that V. sororia has ciliate sepal margins, straight beard hairs, and flowers that sit close to the leaves. Those three characteristics are not typical of the specimens in the photos below.

Do you think V. sororia is the best candidate? I may have to collect a sample for review by the Arkansas Natural Heritage Commission in Little Rock.

Viola sororia will usually key out very close to V. cucullata but the differences in the shape of the beard hairs are as you've described. I will say that the specimens of V. cucullata that I have seen had rather long peduncles compared to V. sororia. You might wait a few weeks before collecting a sample as violets can look different later in the season from when they first emerge. If you collect it press at least one of them as a voucher in case it is V. cucullata.

That's good advice. I have a bad habit of trying to determine species from plants that aren't yet mature. I did get a reply from one of our botanists this morning. They thought the photos were interesting enough, that they forwarded them to a recognized authority in the genus for comment. They also promised to provide a press, since I've sent them photos of several other non-typical species for our area.

I believe these violets are called Wild Violet, Viola or Viola odorata... they grow on my farm in zone 3a. North Central Alberta