Until last week, I had only seen this fungus once before, ten years ago in September 2016, in Cardiff’s Roath Park, but I’ve seen enough photos in the meantime to recognise the shape of its brackets, and the velvety surface and vibrant yellow edges of those brackets.

This is Dyer’s mazegill (Phaeolus schweinitzii), a fungus that’s a parasite on the roots of various conifer species, including pines, firs, spruces and larches. It’s usually found close to the roots of those trees but can occasionally be found on the trunks, and, as this specimen was, on the bottom of a dead, sawn-off pine stump. The fungus is present year round but is only seen when its fruiting bodies appear, between early summer and late autumn.

As to its name, I think you see from my macro photo below where the ‘mazegill’ comes from; the underside of the bracket is covered with an elaborate pattern of spore-bearing pores that resembles a labyrinth or a maze.

And ‘Dyer’s’? In his publication Fascinated by Fungi, Pat O’Reilly writes

There are records going back many centuries showing that certain [fungal] species have been used for dyeing wool and other fabrics. One of these is Phaeolus schweinitzii, whose young fruitbodies provide a bright yellow dye … Because of this use and its variable and misshapen pores, this attractive polypore is commonly known as Dyer’s mazegill.