Agaricus xanthodermus (Yellow staining mushroom)

Image: © Rob Farrow Taken: 3 Oct 2013

This is a fungus that it is worth knowing how to identify, as it looks remarkably similar to a field mushroom but is in fact poisonous. Agaricus xanthodermus can easily be identified however, because its flesh turns chrome yellow when bruised. As a general rule, any gilled white or cream fungus that turns yellow on bruising should be avoided as it is indicative of several poisonous species. When cut, the base of the stipe (stem) of this species should exhibit this colouration, but this snapped stem is only showing a little yellowing. The younger mushrooms, before the cap opens, look like padded drum-sticks - running your finger-nail across the cap of these will produce a deep chrome yellow colour. Note also the fawn scaly markings on the top of the caps and the skirt-like ring near the top of the stem on the open (and upside down) example. See picked example Image] and bruised example Image]

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