I need to learn more about ferns because they are confusingly similar. I got excited that this one was lanceolate spleenwort, which is rare but has a small stronghold in south Devon, but maybe it is common black spleenwort. I thought a key feature might be the opposite pinnae but then noticed that on the other frond they are clearly alternate. Puzzling.
Still no frogspawn in the pond but it is cold enough for the bullfinches to visit the feeder.