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fungus, don't worry about it.

Slime mold

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Slime mold, it's harmeless

Hi,
Yep, its slime mold.
You might want to try raking it on the top of the mulch so its exposed to more air. It needs moisture to keep going.
Personally I would rake it out of the mulch into a plastic bag and dispose of as you see fit.

There's no reason to do anything, it's a natural part of the decomposition process in the mulch. Harmless, as said, ephemeral.

an even better name at the link

ken

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