Grandma Lake Wetlands contains a 44-acre pristine soft water bog lake surrounded by an open mat that supports an unusual and diverse flora. Ringing the lake is a wide, open mat of sphagnum moss, sedges, rushes, and low ericaceous shrubs. Locally, the mat composition is quite unusual, with species such as bog club-moss, horned bladderwort, and a bulrush assuming dominance. A conifer swamp of tamarack and black spruce surround the open bog. Northern white cedar is also present. The transition zone between open bog and conifer swamp is occupied by a muskeg of widely scattered, stunted swamp conifers within a matrix of typical bog vegetation. Of particular importance is the presence of a large population of bog rush (Juncus stygius), a state endangered species that was unknown in Wisconsin until 1982. Other rare plants include bog arrow-grass (Triglochin maritimum), dragon's-mouth orchid (Arethusa bulbosa), and two sedges, livid (Carex livida) and small-headed bog sedge (C. tenuiflora). Insectivorous species are quite common including pitcher plant, narrow-leaved sundew, round-leaved sundew, and several bladderworts. A number of rare birds inhabit this area including black tern (Chilidonius niger), common loon (Gavia immer), merlin (Falco columbarius), and American bittern (Botaurus lentiginosus). Grandma Lake Wetlands is owned by the USDA Forest Service and was designated a State Natural Area in 1996.