Two interesting saprotrophic fungi of wood

With fungi still about in good numbers, not a day goes by when I don’t come across some ephemeral specimens. Below, I showcase two very unique-looking fungi, which are both saprotrophs of wood. It’s likely that – at least, if you’re in the UK – that you have come across both before. If not, then now’s the time to look!

Abortiporus biennis (the blushing rosette)

This dude is weird, and is so impossibly distinctive from other polypores that occur on dead wood (I have seen it on actual stumps and fruiting in grass, where it is feasting on roots below ground after the stump has either rotted away or been ground down) that you don’t even really need a microscope to discern it to the species level. In spite of its common name however, it doesn’t always look like a rosette and can instead adopt a quite obscure morphology where pores are on the upper surface and it stays as a whitish blob (sometimes exuding red liquid – notably when young). Thankfully, when it does achieve its ‘potential’, it becomes a very pretty polypore and releases a white spore that can be found to dust any leaves or blades of grass caught beneath the fruiting bodies.

For ease of understanding what I am on about, I have included both examples below so to illustrate the variability of this fungus. Also note that, when fruiting in grass, the roots it is devouring beneath the surface often leads to the fruiting body protruding out from the ground on a rather long stipe, which I have seen reach lengths of over 10cm.

I have not observed this species in a woodland setting as of yet. Instead, examples have all been limited to urban areas (including parks) where canopy cover is either non-existent or very sparse.

abortiporus-biennis-quercus-stump-1 — In this scenario, we can spot six different fruiting bodies all appearing to sit on top of the grass. At this site, around four years ago, a large oak tree was removed. This fungus has thus colonised the roots left below ground, after the stump was ground down.

abortiporus-biennis-quercus-stump-2 — As we can see in this image, not only has the fruiting body produced the more typical polypore form with a hymenium below and an upper surface with a different texture and colouration, but also – on top of that lovely growth (!) – a very large growth complete with pores atop.

abortiporus-biennis-quercus-stump-3 — Another specimen has grown around blades of grass, thereby assuming them into its structure.

abortiporus-biennis-quercus-stump-4 — This example displays the much more aesthetic form the fungus can adopt, though again we can see the growths atop that are more reminiscent of an anamorphic mass.

abortiporus-biennis-stump-1 — On this stump (likely of ash) we can observe a few fruiting bodies of Abortiporus biennis, though with a very different appearance to those on the roots of the oak above. Here, the fruiting bodies are more bleached in appearance.

abortiporus-biennis-stump-2 — An inspection of one of the fruiting bodies shows how bizarre its form is.

abortiporus-biennis-stump-3 — A cross-section reveals a pinkish-white context with a tube layer ever so slightly darker. It smells very strongly of mushroom, and is slightly soft in texture.

Rhodotus palmatus (the wrinkled peach)

This gilled mushroom is found generally on elm, though can also occur on other hardwoods in the UK. Unfortunately, since Dutch elm disease battered our elm population, it has become a rather uncommon sight amongst the landscape. However, it can still be found, and in this instance I spotted a few of them growing on a cluster of downed elm stems.

This mushroom has a rather pleasant smell, is very soft and moist (almost akin to oysters), and when young has quite the artistic form (as we will see below). The stipe is usually offset, and the cap is a very soft pink (though fades with age, in this example).