Lovely butterfly, Ken. You have quite a spike on the left side of the histogram and I think that's why the blacks in the bottom wings have lost their details. I think fill flash might have been a good idea here so the underneath of the thistle and the side of the butterfly wasn't quite so much in the dark. All in all, I think it's underexposed - you might be able to reprocess it in ACR and pull those blacks back a bit.
I think if this had been more of a vertical and less of a square crop the horizon might not be so bothersome. As it is, the contrast between the really dark trees and the very bright sky seem to be fighting each other. It's certainly not a bad image - just not one of your strongest. You might go back and try a close crop on just the butterfly and the top head of the thistle.