In Dene Park I have found quite a bit of Fuscoporia on over-stood dead Sweet Chestnut trunks, which makes it one of the commoner crust fruiting bodies in this woodland. This might raise the question why it isn't mentioned as a host in H & L - except maybe there aren't many Sweet Chestnuts in Hampshire, especially ?
A closer pair of views of the above, maybe suggesting a largely eroded fruiting body, perhaps not the best for microscopy...
In First Nature, only Fuscoporia ferrea is mentioned, and it is said to be common and widespread in the UK as well as Europe. I think there is a general agreement that Fuscoporia ferrea is the more commonly recorded taxon in the UK. Distinguishing the two is likely to be very difficult and some would say based on microscopy alone. It may be worth checking that the tubes are brown, 2 to 5mm deep in each of 4 to 5 layers, as the tubes seem to be much deeper than that in some of the specimens I have seen; they should also terminate in small roundish red-brown pores spaced 4 to 6 per mm. Kibby on the other hand has the tubes up to 8 mm deep, and concolorous with the pores. What is a beginner supposed to do?
I always find it amazing that despite the bright colours of the fruiting bodies and layers, that the spore print is only white or whitish - it must be difficult to determine of course, as large numbers of spores are required for a print.
Fuscoporia ferrea is mentioned as the cause of a disease of stone fruits in the NBN, but I have found no cross-referenced support. There is the rather similar Phellinus pomaceus.
Distinguishing ferrea from ferruginosa is definitely tricky. In Laessoe and Petersen it suggests that only ferruginosa has setae in the margin. Kibby appears to suggests they are also much larger than the hymenial setae - 300 micrometers - but this is really not implied in Laessoe and Petersen!
On another nearby Sweet Chestnut trunk of over-stood coppice, we may have an example of the false caps mentioned in L & P. Another explanation might be cavities stuffed with brown hyphae -very difficult to interpret!