I have a large, vigorous peony which was sold to me as P.caucasica (now an invalid taxon) and which keys out as P.daurica coriifolia using Hong's book. I have another, smaller, quite different peony sold to me as P.triternata. This also keys out as P.daurica coriifolia. I realise it could be my inexperienced use of the key but it happens every time I try. Anyone have any thoughts?