This species of scarab is often found on oak trees. Rhizotrogus aestivus flies at twilight from April to June and provides a significant food source during this time - especially for pregnant greater horseshoe bats after their hibernation. But there are no greater horseshoe bats in Hesse. The last sighting was in 1924. There are still a few in Rhineland-Palatinate. The bat species is threatened with extinction because it is running out of food and there is less and less habitat available, e.g. old attics.