Dewey Marsh State Natural Area

Dewey Marsh State Natural Area contains a large expanse of relatively undisturbed northern sedge meadow including smaller islands of tamarack and black spruce swamp, paper birch and white pine woods, and ericaceous bog. The marsh is dominated by blue-joint grass, steeple bush and wire-leaved sedges, with cattails and bur-reed. It forms the headwaters of Hay Meadow Creek.

Scattered throughout the Area are islands of aspen, birch, and white pine. Tamarack and black spruce swamps are also present. The eastern arm of the marsh is relatively cold and acidic containing an ericaceous bog while the western and southern portions are more alkaline. Rocks are exposed in many areas and there is little peat formation under the sedge mat. Large areas of peat and several acres of tamarack-spruce swamp, shrub carr, and red oak-white pine forest were destroyed in a large fire in 1976.

Wildlife use is extensive with a diversity of rare species including sharp-tailed grouse, Greater Prairie- chicken, red-shouldered hawk, and northern harrier.

The Area is managed as a northern sedge meadow reserve, a wetland protection area, and as an ecological reference area. The Area also provides opportunities for research and education on the highest quality sedge meadows.

Dewey Marsh is owned by the DNR and was designated a State Natural Area in 1976.

Source: WDNR