It'll be fine. Likely breaking up stuff the worms don't break down easily, esp lignins. My guess would be actinomycetes, which look like fungi but are a bacteria. In my experience common with e.g. cardboard bedding and especially if a bit dry. Not likely to be any harm mixing up and spraying lightly with water, if you want to worry about it, or just leave it.

Agree with armoured, all just part of the composting process......worms will be fine!

This is the exact reason I searched for a worm forum - I've had the same kind of fungus off and on and have been really worried about it, thank you to everyone who responded!

This forum is getting slower and slower though. I'm not using any of the cyber/digital/new age social media thingie. This is my ONLY way of communicating in regards to vermicomposting/vermiculture and I'm worried I won't get any response to a worm bin emergency. Hello 911?

The search "Button" doesn't always work/get you what you need/asked.

Many of the knowledgeable long ago posters have disappeared once GardenWeb became Houzz. What a shame and loss. To me this means there's something wrong with the way things are going/working/not working. Can somebody fix this. PLEASE?

This used to be a very active and thriving community. It cannot be that people stop worm farming because there is a huge demand for worms.

Sorry to have hi-jacked this thread.

Hijack away, glad I'm not the only worm-nerd 😊

@11otis, yes, I often/usually find this type of white growth between cardboard layers and even through the cardboard. Normal for a fungus, I'm also fairly sure the actinomycetes do this as well, particularly if the cardboard is slightly on the drier side. After a while with this, the cardboard breaks down and crumbles nicely, smells strongly of earth.

Hey armoured, you're so knowledgeable. I'm not familiar with ""actinomycetes "" and googled it. This is supposed to be VERY beneficial. Hm, keep learning something everyday at my old age.

They're my favourite faux fungus.