Season (Adult / Immature):
National Status: Common
Local Status: Scarce and thinly distributed or restricted resident.
Local Record: Grade 3 See here for explanation
Flight time: One generation, Jul-Oct.
Foodplant: Oaks and birches. limes, Beech.
|Year first recorded||1961||1985||1961|
|Year last recorded||2011||2011||2011|
|Number of records||564||53||1234|
|Number of individuals||1351||58||2818|
For the region, we have a total of 1234 records from 100 sites. Earliest record on file is in 1961.
Similar species: 1912 Ennomos quercinaria (August Thorn) and 1914 Ennomos fuscantaria (Dusky Thorn).
For further information refer UK Moths.
Davey, P., 2009: A frequent species in southern Britain, more local further north, the larva feeding on oak (Quercus spp.), lime (Tiliae spp.) and birch (Betula spp.). In Dorset, the moth is restricted to old birch and oak woods; it is seldom found in open country. It has also been trapped in suburban areas such as Wimborne, where lime (Tilia platyphyllos x cordata) is likely to the host plant. September Thorns between mid-July and mid-August are smaller and paler than their late-summer/early-autumn counterparts; debate surrounds the possibility that the two forms are in fact two ecologically separate races.