Mölna has many old oaks. The oaks stand both in open environments where they grow beautifully wide-crowned and inside the forest together with old pines. The oak environments at Mölna have high natural values and the forest environments are classified as key biotopes by the Swedish Forest Agency. The oaks are home to unusual fungi such as oak tick and ox tongue fungus, and the oaks are home to several unusual beetles such as the flat leaf beetle, the brown gold beetle and the shipworm fly, which despite its name is a long narrow beetle whose larvae develop in oak wood. Oak timber that was previously stored at shipyards was a favorable place for the larvae to develop. The area is also home to unusual insects associated with conifers, such as the relict beetle and Ipidia binotata - an unnamed beetle whose larvae develop under the bark of dead spruce trees.