The only medium-sized falls below the confluence was edged with Anastrophyllum hellerianum oaks, but there were no Ash in its mist zone and no interesting Lejeuneaceae. Rock shelves on a sharp bend in the river held Grimmia hartmanii and Scapania subalpina, and there were several logs with Cephalozia catenulata and Riccardia palmata. An oak overhanging another low waterfall supported the only Jamesoniella autumnalis I saw during the day, and sphagna on the woodland slopes had me puzzling because none seemed to fit Sphangnum quinquefarium (just S. fimbriatum, S. subnitens and I hope S. russowii, but I have bits to check).
I turned into the Hepste relatively late in the day, so only had time to work upstream to the first pair of waterfalls. These were pretty splendid, but again lacked small Lejeuneaceae. The base of the waterfall cliff appeared to be Carboniferous Limestone, complete with a colony of Seligeria cf. donniana (fruiting, to be checked) and some Neckera crispa. The ravine around the upper falls held a nice patch of Hymenophyllum tunbrigense, perhaps previously unknown, whilst a crevice near the lower falls had scattered patches of Killarney Fern gametophyte over a 20x20cm area. The fungus Macrotyphula juncea was growing out of some damp leaves, and I also saw what I think is Cortinarius cinnabarinus among the Rhytidiadelphus loreus in steep woodland. At the west end of the valley there was a log covered with liverworts, including abundant Lophozia incisa.
A long trudge back past Cilhepste revealed a tuft of Colura on birch on the edge of the woodland/plantation, as well as some lovely growths of various Usnea species.
Sometimes one builds a day up too much and ends up disappointed: this was a good day out by almost any standards, but the Nedd-fechan left me expecting excitements every time!