Rishworth - Tussocks of Birch!

Had an absolutely freezing night with a fare bit of frost. This morning (07/05/2020) I came to find...…
Grey Birch x1
Pale Tussock x1

One could understand why a Pale Tussock would come on a night such as this with all of his winter furs as insulation. As for the Grey Birch in Geometridae of which have no insulation I don't know what it is doing in this cold night. Tonight (Thu) and Tommorow Night (Fri) are looking rather warm so the trap will be run and hopefully we get some nice moths. Any comments v welcome...