I passed these mushrooms on my walk to work. They were growing in a grassy area, under trees, and next to an old stump. There were a few little clumps poking up through the grass, in a patch a couple of metres wide. They weren't far from my office, at Woods Mill, so I decided I'd go back at lunchtime for a closer look.
Preliminary investigations revealed a dusting of brown spores on the caps beneath the uppermost mushroom.
This put paid to my first theory – that they might be Fairy Ring Champignon Marasmius oreades – because they evidently don't have a white spore print.
The most striking feature of these mushrooms was their growing habit: sprouting up in a clump and strongly fused together at the bottom. The other thing I noted was their brittle stems which made an audible snapping sound when even slightly bent; and no ring around the stems.
Flicking through the Collins Complete (photographic) Guide that I now try and carry around with me wherever I go, I couldn't immediately see any candidates which matched what I was seeing. But then the photographs in that book are almost all taken looking down upon the cap, which doesn't give you much to go on when trying to match other features such as the gills and stem.
I took a specimen and resolved to investigate further, after work.
Once home, I took my copy of Mushrooms by Roger Phillips off the shelf and flicked through it, looking for something to match what I'd seen. When I got to this page – the Psathyrella – I reckoned I must be pretty close.
Feeling cocky, I then turned to Funga Nordica, to see if I could key out my mushroom. But I got stuck trying to determine if it had pleurocystidia or not, as I wasn't sure what I should be looking for.
I did have some success measuring the spores. I think these are about 8 microns in length.
And – not very easy to see when they're just mounted in water – but I think these are cheilocystidia growing along the gill edge. Their skittle shape, which you may or may not be able to make out in this photo, is described as 'utriform' in mycology-speak.
I didn't quite manage to get through the keys to the Psathyrella – they include some tests I can't do because I haven't got the right kit (e.g. ammonia). But I think my mushrooms are a good match for Pale Brittlestem Psathyrella candolleana.
I was unsure at first because Funga Nordica describes the cap as "dark reddish brown, becoming ochraceous brown, at maturity fading to ochre with yellow, grey, purple or violet tinges" and I don't think my mushroom is any of those colours! However, it goes on to describe the cap as "hygrophanous, drying sordid white or grey". Well, I guess you could describe the cap as "sordid white". Although that seems an extraordinarily odd description for a colour. The colour of Miss Havisham's dress, perhaps, after all those years shut up in her mansion?
I couldn't see any trace of a veil, but I think these mushrooms were a couple of days old by the time I got to them, and the recent heavy rain could have washed this away. I noticed the fresher caps have a slight sparkle to them, when you get them up close; I don't know if that's indicative of anything. And the margin is faintly striate.
The habitat and time of year also seems right for P. candolleana, as Funga Nordica describes it as occuring "in rich deciduous forests, parks and gardens on or around stumps...; spring to autumn."
So, P. candolleana seems quite likely. But I wouldn't like to say for certain as Psathyrella seems a more complicated genus than the field guides would have you believe.
For the record
Location: Hoe Wood
Grid reference: TQ217136