Three coniferous swamp communities intermix in areas of peaty soil in the park. Black spruce bogs have a dense canopy of black spruce, a shrub layer of black spruce and speckled alder, an understory of bog Labrador tea or leatherleaf depending on shadiness, and a ground cover of sphagnum. Tamarack bogs have an open canopy of tamarack with plenty of black spruce, a shrub layer of speckled alder and dwarf birch, and a very dense understory of leatherleaf with bog-laurel and bog-rosemary over sphagnum. White cedar swamps are characterized by northern white cedar with black spruce and balsam fir, dense speckled alder shrubs, and less understory and sphagnum than the other communities.