Adult moths from an ecological group of winter geometrid species look for trees where they copulate and females lay eggs. We investigated how tree trunk and lower branch thickness affects the occurrence of females on trunks and branches and how the density of females and tree trunk thickness affects the occurrence of males on trunks. The research was carried out in a xeric thermophilous oak forest in southern Slovakia (Central Europe) in the winter season 2014–2015. The moths were obtained from