Taphridium umbelliferarum

A fungus affecting the leaves of certain umbellifers, often Hogweed.  The leaves are covered in large yellow/grey patches, which are slightly raised and have a puffy appearance, although this is not listed as a gall.  Chlamydospores are embedded in the upper leaf epidermis; these are thick-walled resting spores that can survive periods of unfavourable environmental conditions. 

This fungus may be confused with the normal yellowing and chlorosis that can occur on umbellifer leaves

host

Photograph the fungus on the host, including in close-up.  Ensure you have noted the host species in your comments.This species has rarely been recorded in VC55, so we recommend that a specimen is retained for verification; microscopic examination may be needed.

Umbellifers, especially hogweed; roadside, hedgerows, rough grassland, woodland edge

Rarely recorded