The nutrient-poor gneiss must take most of the blame for the scarcity of deciduous forest in Masfjorden. The ground soil needed for warm-loving trees is almost only found in the lowland, under steep mountains, where there are a lot of scree deposits. On the steep slopes that face southwest along Lake Storevatnet in Andvikedalen, one finds old lime and elm trees growing (picture). Some of these trees are unusually thick-trunked, with diameters of well over en metre. Most of the trees have never been pollarded, and this gives a sense of native forest. Another area with rich deciduous forest is the lower parts of the steep, south-facing slopes in Matresdalen. On the forest floor, a lot of wood fescue and wood sanicle grow among the elm, lime and hazel.