The first nice find was this crested form of Lady-fern (Athyrium filix-femina). Not sure if it is a chance mutation or if it originates from a spore blown in from a garden plant. It seems close to the cultivar 'Vernoniae Cristatum', but there is a danger in linking wild plants to cultivars if you are not sure if they breed true. In this case the name was probably originally applied to a specific clone, and I doubt the name should be used to cover all similar crested forms.
The other big surprise was a stand of Giant Marsh-marigold (Caltha palustris subsp. polypetala). A well-intentioned but unnecessary introduction of a non-native form by "do-gooders". My A4 Weatherwriter and the Yellow Iris (Iris pseudacorus) both provide a useful scale against which to judge the size of this plant.
Some sources say this originates from Turkey, but I am not convinced the plant circulating in the horticultural trade is the same. For starters it is not polypetalous. It may be a cultivar rather than this subspecies, but the name must do for now as a label for these distinct giant plants. What is certain is that it is increasingly being found in semi-wild situations where aquatics have been introduced for amenity and "nature conservation" reasons.
Other interesting finds included an extensive and very diverse hybrid swarm of Geum x intermedium below the dam of the lake, where it was present with both parents. There is also a large bush of Gagnepain's Barberry (Berberis gagnepainii) near the dam.
