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... Hesperis matrionalis (dame's violet) - they're too big for any willowherb other than great willowherb or rosebay. There isn't a clear view of the associated foliage.
The stems in the foreground appear to be Epilobium hirsutum (great willowherb).
I agree with dame's violet - actually, we thought 'honesty' for a mo in the filed, then noted leaves too lanceolate. I haven't come across this knowingly before, but very much a beginner in plants.
You can see the relevant leaves if you zoom in and look down the stems and they are a good match for DV in the book. It is probably great willowherb around it as it's in an area I've seen that in the past, I think - we'll see when it flowers.
Paul Seligman. Flickr: http://www.flickr.com/photos/paul_seligman_cardiff/collections/721576087...
Lat/Lng: 51.48561, -3.26789
OS grid ref: ST120770
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