Contrary to its venacular name, this species does not feed on oak. It is so named because of the shape of its cocoon.
Males fly during the day, females fly from dusk and come to light with the first few hours of darkness.
Pupates in a brown cocoon in leaf litter.
Heathland, woodland, grassland, hedgerows, scrub and fen.
Recorded in 26 (9.6%) of the 270 2km squares of Huntingdonshire.
Last recorded in July 2019
Recorded date range (Adult): 04 June to 10 September
Recorded date range (Larva/Leafmine): 17 May to 04 June