Coniferous woodland, heathland.
Common throughout the British Isles. Adult moths can be easily disturbed during the day and come to light at night, often in large numbers. The larvae feed on a range of coniferous trees including Norway Spruce, Scots Pine, Douglas Fir, Lawson's Cypress and Monterey Cypress.
A very variable species in size, colour and markings and can be difficult to separate from Thera britannica (Spruce Carpet). Compared to Spruce Carpet it is usually light red-brown to dark brown rather than grey and is more lightly fluted narrowing dorsally, however, this can vary considerably.
Recorded in 66 (96%) of 69 10k Squares.
First Recorded in 1840.
Last Recorded in 2020.