What on earth is this?

[Hippobot]

I've an old wooden shed in my garden that's going to be taken down tomorrow. I went in today to clear everything out of it ahead of it being dismantled and found masses of this horrible looking substance. I have absolutely no idea what it is. The shed has some holes and gaps in the walls so it's not watertight and creatures can certainly get in. Is it some kind of fungus? We have lots of snails in the garden but surely snails couldn't poo that much? Please help. I'm scared to disturb it without knowing what I'm dealing with and google image search hasn't been any help.

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%3D

😱 no idea! It’s either the cure for something or the next pandemic!

It looks like snail poo to me.

They eat the labels off tins, containers etc. Then they poo this…

I think it's an algae called nostoc, also known as witch's something hideous looking thing

It is hideous indeed. I've looked up nostock and, whilst it does look a bit like it, this stuff is more grey than green and it's kind of dry/powdery whereas nostoc is slimey/damp. It's mostly on top of a lawnmower and on top of a plastic box lid - both dry.

There is a cardboard box near this stuff that looks like it's been eaten. Would snails eat it and poop like that? There is just so much of it - it's the sheer volume that had me doubting the snail poo theory. Do they make big piles of faeces over and over in the same places?

How big are those pieces of material?

They do, yes. I left a few boxes of leftover kitchen and bathroom tiles out on my shed porch. Meant to do something with them but kept putting it off. Now the tiles are just sitting there with piles of snail cardboard poo all around them, the boxes have been completely eaten 😂

Thanks so much for this thread OP.
Explains what's been going on in my garage.
I assumed birds but snails makes much more sense.
Could be a useful recycling process.

A few centimetres.

Yep, snail poo. I have a tub of old pots to reuse in my shed and it's full of the stuff. I think they either arrive in the pots, or eat the organic matter in any remaining compost then relieve themselves in situ.