Hapalopilus nitidans, the Cinnamon Bracket or Tender Nesting Polypore.

The UK's only toxic polypore - and it is HIGHLY toxic with a very high content of polyporic acid.

While with the Kent Field club group, we found a very lovely looking triangular bracket fungus on a small dying or dead tree. I would describe the form as "stepped". I tentatively identified the host as a Rowan or Sorbus tree and somebody who I think must have seen this bracket fungus before, tried putting some potassium hydroxide, KOH, on it. It almost immediately turned a bright violet colour suggesting that it was the toxic cinnamon bracket. Hapalopilus nidulans, a very difficult name to spell. I was pleased to say that Lassoe and Peterson also consider it quite commonly found on Sorbus. However, other sources just give it as found on mixed deciduous trees or possibly Oak and Birch. It was a delightful colour and an interesting texture on the top surface. All the factors seem to fit, so a nice step forward in bracket identification for me.

Also referred to as Hapalopilus rutilans, it might be rather commoner in Europe, but is said to be only occasional in the UK. Records in the UK seem to fairly evenly distributed north to south. This is an annual polypore bracket, breaking down to a rather dusty debris. However, these 2 or 3 brackets were quite fresh.

Note the texture of the top surface, sometimes likened to suede. The top is said to be flat to slightly convex, the overall texture of the bracket soft.

Said to be typically "triangular" in shape.

The pores are quite coarse and strongly delimited in appearance. 2 - 3 per mm. Tubes reportedly up to 1 cm deep, spore print white. There is a fairly clear margin to the underside, extended rollover in the later stages.

Junghuhnia (Steccherinum) nitidum or just possibly lacera?

Slightly more lacerate than usual, but not a British species I think. Impossible to resolve without measuring the spores under a microscope, but I should have tried to measure the pore density at least.

Stereum rameale or Chondrostereum purpureum perhaps?

 Found on a small fallen branch about 15 - 20 mm thick. Each cushion with a darker central hub, highly shaggy on the reverse side, often curled up to form a one sided cap. Fertile surface cracked so could be old and decrepit maybe?

I am completely stumped within Stereum as a genus. The fertile surfaces look like photos on the internet named as "Stereum rameale" but the shagginess is completely out, a much longer pile than Stereum hirsutum, supposedly the hairiest one in the genus. Only thing I can think of that is quite this shaggy is Silverleaf, Chondrostereum purpureum, perhaps old cushions from last season, so that all the purple has been long ago washed out? 

Wet Rot, maybe

I think this must be the very young stage of Coniophora puteana or one of its close relatives. There is no colour in the centre, but the texture is very reminiscent of this species, coupled with the furry nature of the edges, the fine white extensions. Interesting to think what these might be for, evolutionarily? Would I be able to find this log again? Very doubtful.

Bjerkandera adusta

 

The Smoky Bracket, Bjerkandera adusta, is a very common fungus, which can be found in a fully prostrate form (effused), as well as as, perhaps much more commonly, caps (reflexed).

It should always be pressed on the pore surface to see if it darkens upon pressure. Also cross-sectioning the tissue should reveal the grey pore layer contrasting well with the white flesh. Bjerkandera fumosa has lighter coloured pores, separated from the white flesh by a dark line.

Today, there were a number of individual fruiting bodies, mostly resupinate, on fallen branches of Oak in the first Oak compartment to the north of the car park at Dene Park. 

There was evidence I think of the very yellowed flesh of previous fruiting bodies below and behind the current ones, and some slightly yellowed flesh of the current brackets visible in the gaps of the larger fruiting bodies seen here. Some clear and some cloudy liquid droplets on this lower surfaces. In some places the flesh is reflexed to start cap formation, although why is less clear. However, compare with the possibly more developed complex fruiting bodies seen at Dunorlan Park on the 5th November, 2011.

This other large resupinate fruiting body appears to show more small developing caps, and also maybe  a couple of patches of the pore surface darkened by pressure.

 

Here the fungus has used a leaf as support to produce a thin resupinate structure quickly and easily.

Here is an old cap, decaying, brown and fibrous.

And here is a Springtail, possibly Tomocerus vulgaris!

Biscogniauxia nummularia - Beech Tar Crust or Charcoal Canker

 

I think this is most likely to be Biscogniauxia. Stated to be a significant parasite of Fagus sylvatica if the environmental conditions stress the tree in various ways - increasing risk drought is perceived as a bit of a worry for European Beech in Southeast England.

This is a section of dead hardwood in the trunk of one of these trees to the east of the main track from the car park at Dene Park. The fruiting body "erupts" through the bark nicely.

Are there any clues to why this bark appears dead in this image here? There is good evidence that these species occur in healthy living trees as endophytes and then become invasive under water stress conditions. Could the initial carving have possibly caused this overall wound that allowed a strip canker to get to work, and we are now seeing the results as the fruiting bodies appearing, perhaps later through the letters themselves?

Here, these fruiting bodies are just appearing recently on the heartwood of this large branch on the ground that tore away from the trunk maybe a couple of years ago. 

The species used to be known as Hypoxylon nummularium: this should now always be known as Biscogniauxia nummularia (Bull.) Kuntze. This genus is distinguished from Hypoxylon principally in lacking coloured stromatal pigments and in having an initial covering layer, lost at maturity, which bears conidia. Many species have effused and flattened rather than pulvinate stromata.

Biscogniauxia atropunctata is a saprophyte and parasite affecting oaks east of the rocky mountains, It starts as a blue-white fruiting crust with tiny black pimples, eventually darkening to black patches on dead and dying wood.

Biscogniauxia mediterranea is well known as the causative agent of charcoal canker in cork oak and is a serious problem in Portugal.

Biscogniauxia rosacearum may possibly be one of the main fungi that feed on grape vines and almonds.

Biscogniauxia species that produce interesting secondary metabolites can also be found in deep sea sub-floor sediments!

Arcycria denudata possibly

Picking up a fallen branch from the leaf litter, I eventually spotted a few brick-red slime mould fruiting bodies, which might be the relatively common Arcyria denudata, purely on the basis of colour and probability. Microscopy would be needed for a reliable identification. I might be able to find the branch again, to see if the condition of the fruiting bodies has improved at all following the freezing conditions over the past week.