This is Schizophyllum commune (a split-gill), which usually grows on wood, but is also found on bales of hay or straw. It can be pathogenic to humans, having caused mouth ulcers and toe-nail infections. For detail see [[2939765]].
Uploaded to Geograph by M J Richardson on 8 May 2012
Photo © M J Richardson, 8 May 2012.
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