Skuleskogen is located on the northern border of the range of several plant species. Thus several deciduous tree species are present in the park, such as the little-leaf linden (), the common hazel (), the guelder-rose (), and the Norway maple (). The presence of these species is considered more of a relic of a warmer era than a feature of the current times. Their survival has been rendered possible by the unusual conditions encountered at the foot of certain mountains called (literally "mountain of southern-like vegetation"): the orientation of the rock face to the sun and the humidity brought about by the mountain offer a favorable microclimate which, in conjunction with the fertile soil, permits plants which do not normally grow at so high a latitude to thrive.