A small, annual polypore with whitish brackets that develop bluish colours as they age.  The cap has fine hairs and ridges.  The pores are rounded or elongated/maze-like, and small at 5 - 6 per mm. 

Postia caesia is similar but found on coniferous wood.  Postia alni is also present on deciduous wood and described as less hairy, but it is very hard to distinguish from P subcaesia. 

host/microscopy

Photograph upper and lower fertile surface to show pores; note host plant and substrate.  Identification by an expert from microscopic examination of a specimen is needed before submission to NatureSpot. 

Deciduous wood

Fairly frequent in England occasional elsewhere.

Occasional in Leicestershire and Rutland.