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What feature are you using to distinguish from Viola odorata? I find this often has no detectable scent and have to search for stolons to decide.
Flowers unscented, spreading hairs on petioles 0.3-1mm and blunt sepals.
Leaves and flowers from rootstock, but also growing on Calcarious grassland. Leaf shape also appears a little more delicate than V.odorata.
Hairs on petioles > 0.3 mm (as you say) and patent (not deflexed);
ligules lanceolate (not ovate) I think but hard to see.
Desperately trying to learn Viola! Problem is, I can't see any petioles in the photo, only the flower stalk (pedicel) and none of my books mentions this. If you mean stipules, as you say, also hard to see. Many sources mention leaf shape, but this seems to be very variable and depends on the stage of growth. Perhaps the habitat is the giveaway?
I cant see any petioles, only the pedicel. I must have been confused.
The easiest way is the presence or absence of stolons
but it is not possible to tell from these photographs.
I show petiole and ligules of V. hirta here http://www.ispot.org.uk/node/256891
Thanks Martin, great photos! I've been out and fetched some samples of Viola odorata (stolons present) and had a really good look with my hand lens. It's not as hairy as the V. hirta, the hairs are a mixture of patent and retrorse. To be honest, the stipule looks exactly the same as the V. hirta in your photo. I think you're right, stolons are the way to go. Thanks again for all your help!
Lat/Lng: 51.9602, -0.3729
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