Graffham Common Fungus Walk

Image © Katie Parker

I had my first experience of leading a fungus walk on Wednesday at Graffham Common – sharing what I've learned about fungi with some colleagues from the Sussex Wildlife Trust. 

Previously covered almost entirely in pine plantation and rhododendron, Sussex Wildlife Trust is in the process of restoring this site to wooded heath with an acid pond which is great for dragonflies. Ecological monitoring has found a fabulous diversity of rare plants and invertebrates here, and the site is also providing habitat for many notable birds – you can read more about this on Graeme Lyons' blog: The Lyons Den.

We started the walk on Gallows Hill. It says something about what an open landscape this must traditionally have been that this was once where criminals were once left to hang, where they could be seen from miles around.

View from Gallows Hill across Graffham Common.

I did warn my colleagues we'd probably find lots of mushrooms that I wouldn't be able to identify. But, fresh back from that fungal identification skills course in Barnsley, I decided I'd collect some specimens and have a shot at identifying them when I got home.

Here they are all laid out ready for step one: get a spore print!

The walk started off with a nice easy one to remember: Turkeytail Trametes versicolor, growing on the end of a rotting birch log.

On the same log we saw the smaller, orangey fruit bodies of Hairy Curtain Crust Stereum hirsutum. Always a crowd pleaser.

There were also earthballs Scleroderma sp. galore. Including this massive one.

I still haven't got my head around identifying earthballs to species. I they were probably all Common Earthball Scleroderma citrinum but not 100 % sure.

Then things got interesting!

We saw masses of these striking orangey-brown mushrooms trooping across the ground, amongst the pine litter.

The younger ones were very cute with their little button caps.

The mushrooms had streaky stems, with contrasting dark and pale fibres; as you can see here:

Here's what those gills look like in cross-section.

And they dropped a copious amount of white spores.

After a not-very-successful attempt at using the synoptic key to genus in MycoKey, followed by much flicking through my field guides, the penny finally dropped. They are a deceiver Laccaria sp. of some kind.

I narrowed it down to either The Deceiver Laccaria laccata, or the Scurfy Deceiver Laccaria proxima.

The Scurfy Deceiver Laccaria proxima is found on acidic soils, in coniferous woodland and on heaths. Which is exactly the sort of habitat we found these mushrooms in.

One article I read (on Michael Kuo's website, here) suggested you can tell the two apart by looking at the spores: "the spores of Laccaria laccata are round (or nearly so), and have fairly prominent spines; the spores of Laccaria proxima are mostly elliptical in outline, and have smaller, less prominent spines." I can do this! I thought. Until I tried to look at the spores: they are white and it's very difficult to see the spore ornamentation when they're mounted in water. I looked on the BMS website to see if they had any advice on what chemicals to use, to get a better look at the spores:

Phloxine B. Never heard of it!

But by this point I'd got all fired up about the prospect of seeing some spore ornamentation, so I thought I'd have a go at staining the spores with Cotton Blue and see where that gets me.

Hmm. Well. You can tell that the spores aren't smooth and, when you twiddle the focussing knob, you can just about make out some not-very-prominent spines. Plus they are mostly elliptical.

I think the balance of probabilities is tipping towards my collection being the Scurfy Deceiver Laccaria proxima.

It's worth pointing out that the key to Laccaria in Funga Nordica doesn't make much of the difference in the spores. The main features they use to separate the two are:

• Whether the cap is "smooth to tomentose [covered in hairs]", or "scaly"; and
• Whether the thin fibres on the stem are contrasting, or not.

Looking at the species descriptions in Funga Nordica, I'm pretty sure that what I've got here is the Scurfy Deceiver Laccaria proxima.

Next up, we saw quite a few of these yellowy-orange mushrooms, with a pronounced nubbin (or 'umbo') on top, growing on decaying conifer logs.

Image © Katie Parker

Image © Katie Parker

I couldn't see any trace of a ring around the stem.

And the gills were yellow; turning orange with age.

 These have produced a rusty orange spore print.

MycoKey worked well on this occasion, taking me to the rustgills Gymnopilus sp. This genus includes quite a few species which occur in Britain, many of which look quite similar.

From the Collins Fungi Guide by Buczacki et al.

Gymnopilus have cells on the edge of their gills, called 'cheilocystidia', which can have quite distinctive shapes. I think this is one, in the centre of this photograph:

1000x magnification; mounted in water and stained with Congo Red.

Given that these mushrooms were growing on conifer wood, and given the appearance of the cap and stem, I'm leaning towards this mushroom being Common Rustgill Gymnopilus penetrans. The shape of the cheilocystidia would fit with that, I think.

OK, next mushroom! This one was growing on an old burn site, on sandy soil.

It has a quite different shape to it, compared to the previous two mushrooms we'd looked at. I thought at first it might be a milkcap Lactarius sp. but it didn't produce any milk.

The spore print is white.

I think this takes us to the funnels Clitocybe sp.

Flicking through Roger Phillips' Mushrooms, there's one Clitocybe that looks like a good match for my mushroom: Clitocybe sinopica, which is found "in coniferous woods, especially in burnt areas". Although Roger Phillips notes that it's "uncommon".

A quick check on the old FRDBI database picks up only 132 records for this species in Britain, ever. But there are a handful from West Sussex, including a record from Ambersham Common in 1990 which is just up the road. So it's not entirely implausible. But if you're recording something that uncommon, you want to be sure that's definitely what it is.

Turns out one of the key features of Clitocybe sinopica is a strong 'farinaceous' (starchy) smell. Unfortunately I forgot to give it a good sniff out in the field and now – three days later – the mushrooms are rather dried out and don't smell of much. So I decided to seek some advice on the British Mycological Society Facebook page.

I got some advice from Ken Burgess, who suggested I start off by looking at the spores, to make sure I've definitely got a Clitocybe.

1000x magnification. Mounted in water.

I've got that problem of looking at white spores under white light again. But you can just about make out their elliptical shape. Inside the spores you can see little bubbles of varying sizes; these are oil droplets.

The next step is to measure the spores. For this I thought I'd stain them in Cotton Blue, to make them a bit easier to see.

I've previously calibrated my microscope, so I know that one minor unit on this scale is about 1 micron (1 thousandth of a millimetre). That makes the spores about 4 - 5 microns wide; and 6 - 7 microns long.

This then kicked off quite a lengthy discussion with Ken Burgess and Malcolm Storey, over on the BMS Facebook page, as it takes me into an area where there have been some recent taxonomic changes...

The spores are, arguably, a bit on the small side for Clitocybe sinopica and at some stage another (very similar) species was described: Clitocybe subsinopica, with smaller spores. So, based on spore size, my mushroom would seem a better fit for Clitocybe subsinopica. However, Malcolm Storey advised that, in a more recent round of taxonomic changes, these two species have now been lumped together again, under the name Clitocybe sinopica.

Indeed, Funga Nordica treats the two names as synonymous with each other:

Malcolm left me with a wonderful piece of advice, which fits rather nicely with the title of this blog:

"Only beginners are absolutely certain of their IDs. For the rest of us they're the best we can do with the books and papers available at the moment."

I was tempted to call this one Clitocybe sinopica and be done with it. But then Richard Shotbolt picked up that my spores have very strongly taken up the Cotton Blue stain. In mycology-speak, this makes them 'cyanophilous'. Richard pointed out that Kuyper, in his publication – Flora Agaricina Neerlandica – on the agarics and boleti occuring in the Netherlands, states that Clitocybe sinopica is "not cyanophilous". Which leaves the identity of this mushroom something of a mystery...


Right, well, if you can believe it, I've now been writing this blog for about three days. Time for a nice easy one:

Tawny Grisettes Amanita fulva were popping up all over the place. I remembered them from when I encountered them at Ambersham Common.

Then, growing on a sandy, moss-covered bank, next to the track, we saw these:

Here's what one of them looks like up close:

The spore print is a slightly-creamy white.

Flicking through my field guides, it looks to me like it could be something like the Heath Navel Lichenomphalia umbellifera. I'm not sure I've got any more microscopy in me right now, otherwise I'd check it.

Further down the track we encountered masses of what-I'm-assuming-is Sulphur Tuft Hypholoma fasciculare.

They were growing all along the edge of the track, at the base of the bank.

I've seen this species before, growing on rotting logs and wood piles. But I've never seen them growing like this. The Collins (illustrated) Fungi Guide says that Hypholoma do occasionally grow on "impoverished acidic soil".

I'm pretty sure they are Sulphur Tuft Hypholoma fasciculare...

There is another similar-looking species called Conifer Tuft Hypholoma capnoides which the first-nature website describes as having "pale grey gills with no hint of green". But the gills on my collection are definitely greenish.

We also found Earthfan Thelephora sp. growing in various places.

I think this is Common Earthfan Thelephora terrestris. But there is another species, the Carnation Earthfan Thelephora caryophyllea which looks similar. According to the Collins (illustrated) Fungi Guide, one has "warty to knobbly" spores, and the other has spiny spores.

I've got a spore print – it's brown. So let's see if we can see any knobbly-ness.

They look pretty knobbly to me!

So let's call that one Common Earthfan Thelephora terrestris.

I'd like to say that's the end, but I did also find some other little brown jobs growing on the hard standing, which seemed to be made up of gravel and wood chippings, where I'd parked my car. There were quite a few, dotted around.

These are the kind of mushrooms I'd normally pretend I hadn't seen. But, armed now with some basic microscopy skills, I thought I'd give them a go. 

I think this two-tone coloration on the cap makes them 'hygrophanous', which just means the cap changes colour as it dries out.

The gills are fairly crowded.

The gill attachment is – I'd say – 'adnexed', i.e. narrowly attached to the stem. And, if you look closely, you can make out long streaks or grooves running down the stem, which is slightly bulbous at the bottom.

It has produced a fairly copious brown spore print.

After consulting with MycoKey, I think this may be one of the conecaps Conocybe sp. Another really difficult genus. I think I'll leave this one!

For the record
Date: 13 September 2017
Location: Graffham Common
Grid reference: SU9319

C. sinopica specimen retained (ref. CMB00001).

Records entered into FRDBI 06/09/2018