After a year and a half, here again plants portraits from Perigord in this blog.
Ferns are spore plants. In their life cycle very small plantlets called prothalli develop from spores. The prothallus does not look at all like a fern as we know it. Structures for sexual reproduction, also very small, grow in its surface and after fecundation the sporophyte, the 'real' fern, the plant we recognize easily as such, begins to growis born. If the fern is mature it begins to produce spores and the cycle can start again.
Most ferns need humidity in the prothallic stage, without moisture there cannot be fecundation. No problem in mointainous areas with shadowy slopes and lots of water flowing over rocks, but here in Dordogne where water seeps away through porous limestone it can be more complicated.
So Perigord is not especially rich in ferns. But especially in wooded valleys there are beautiful spots full of ferns. Like here below, on an old path where the remains of the stone walls that bordered it once are still visible.
Here we see many 'tongues' of Hart's Tongue Fern (Asplenium scolopendrium), in the centre on top of the 'wall' a bunch of simple divided fronds of a Polypody (Polypodium sp.) and a bit more to the right smaller and thinner fronds of another fern, Black Spleenwort (Asplenium adiantum-nigrum).
Here is its portrait in spring when the new fronds emerge. Black Spleenwort (Asplenium adiantum-nigrum) has black stems and twice-divided pinnate fronds.
It grows in deciduous woods, especially Oaks and Hornbeams, but also in mixed forests with Sweet Chestnut, and sometimes it accepts places where there is sunshine during a part of the day.
It does not need much soil, a hole in a wall is enough! To grow, Black Spleenwort prefers places not completely horizontal, but generally it does not want complete verticality.
This elegant and subtle fern is never more than half a meter high.
Besides a forest track under Downy Oaks, Black Spleenwort has grown into a big colony. In May some of last year's fronds were still present but they turn yellow and will soon be gone.