Caution: Do NOT use iSpot to identify fungi to eat!
Some fungi are very poisonous so a mistaken ID could have serious consequences.
No interactions present.
It was fruiting on the ground, but on the edge of a pile of sawdust
Did it have any kind of stem? It might be a morel of some kind, habitat and general appearance might fit.
However to me the structure of the brown curly bits looks slightly wrong for morel, more like a 'gone over' cauliflower fungus. do you know what kind of sawdust it was, I have not seen cauliflowers growing on sawdust and i think they almost always grow on conifers the ones i've seen have all been on pine although sometimes appearing to be on the ground a little way away.
is imported "mulch" (often used in parks, for example), then it could be non-native.
It didn't appear to have any kind of stem, no. As for the sawdust, it might well be imported- it was from that compressed pellet cat litter stuff, so goodness knows from what origin!
It was at the top of our garden, which is under some mature oak and birch trees.
Well keep an eye out for more of it and check for stem and perhaps get a shot of it in situ as well. also was it in a layer covering the sawdust or in distinct heads like the pictures of morels.
Lat/Lng: 51.806606, -3.907788
OS grid ref: SN685137