Along one of the many tracks in the Mereworth Woods complex running North above Gover Hill, I found many hundred basal rosettes of a Rorippa species, almost, but not quite certainly, the Marsh Yellow-Cress, Rorippa palustris. This is an annual or short-lived perennial which appears to generally spread by seed, so it may have had some good years recently. It is much more successful at seed set than its rather more perennial relative, Rorippa sylvestris.
Some of the plants were a bit larger, with some with upright stems bearing some developing flowers, but there were no flowers actually out to measure the size of the petals or compare the relative size of the sepals and petals, and it was far too early in the year for fruit size and shape to be assessed, as the first few were just being formed, so I was unable to be absolutely sure of the identification. I did look carefully at as many of the stem leaves as I could find, and I thought that they were not as fully pinnately divided, nor with the really narrow lobes of the Creeping Yellow-Cress, Rorippa sylvestris, the most likely other Rorippa species that could be found here. Further evidence was the apparent absence of the creeping roots of the perennial Rorippa sylvestris, and the guidance of the KBRG records indicating the presence in this and the neighbouring tetrads of only Rorippa palustris.
Slightly worrying was the persistence of the rosette leaves. Perhaps this refers to plants that continue into post-flowering or into the second year?
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