fern i.d. please

[Graham Barker]

hello
i live in east sussex, i was doing some conservation work on a local site just outside hastings, and foound this fern, but i dont seem to be able to find an i.d. for it.
it is in a wet area on the edge of a ditch, growing next to or on a willow stump (wish id taken more notice now!)...
when i first notice it, whilst cutting some willow, i thought, thats interesting, i havent seen that before (well, probably just never noticed it before actually)...though it became more interesting when i turned over the leaf and found lots of orange spots on all the leaves....fabulous....
any help is appreciated...many thanks in advance....
graham

[RobSutton]

Looks like Common Polypody

[Dorts]

Yes, as Rob has said, it's Common Polypody - Polypodium vulgare . It is a common native fern, often epiphytic on trees, also on damp walls, banks etc.
The orange spots are the sori, cluster of sporangia that contain the spores. Many ferns have these on the underside of the leaves and can often be a good ID aid, as the shape and arrangement varies on different species.
Dorts.

[Graham Barker]

rob and dorts....thanks very much....very interesting and something i must start to take more interest in....(so much to be interested in and so little time!!!)....
best wishes
graham

[pleb]

For those who are interested, here are photos of the three Polypodium Ferns, showing the different shapes of the fronds. Easily confused because the three ferns are variable and also hybridize.

Common Polypody, Polypodium vulgare



Intermediate Polypody, Polypodium interjectum



Southern Polypody, Polypodium cambricum



phil

[Dorts]

Thanks for that Phil, a very usefull ID aid for anyone interested in ferns.
Dorts.