Oak Processionary

First found in London in 2006,&nbsp;a colonist of south-east England, and possible immigrant.&nbsp; In Europe it is a pest species,&nbsp; whose larvae feed in large numbers on Oak trees, causing severe defoliation. The hairs on the larvae can cause a severe, possibly dangerous, rash on human skin and breathing difficulties. Cases should be reported at&nbsp;https://treealert.forestresearch.gov.uk/. There is one county record in 2013.

Common Emerald

Widespread and frequently encountered right across Somerset, though rather less 'common' than the distantly-related Light Emerald which is the most numerous of the emerald moths in the county.

Small Grass Emerald

Nationally scarce and declining, restricted mainly to heaths in Hampshire, Dorset and the south-west. In the county,&nbsp; it has been recorded irregularly in small numbers, at scattered locations. The species needs to be distinguished with care from Little Emerald.

Small Grass Emerald

Chlorissa viridata