Brunsweiler River and Mineral Lake

State Natural Area (No. 421)

Location: Within the Chequamegon-Nicolet National Forest, Ashland County. T44N-R4W, Sections 10, 11, 14, 22, 23. 1,523 acres.

Access: The site is located 8 miles west of Mellen. Take County Highway GG to FR 187, which passes along and then through the site.

Description: Brunsweiler River and Mineral Lake features a scenic, rocky river gorge incised in an upland of Keweenawan granite bedrock, and several high quality old growth hemlock-hardwood stands embedded in a large tract of maturing northern mesic hardwoods that includes some of the largest yellow birch on the forest. The closed canopy northern mesic forest is dominated by sugar maple, hemlock, and yellow birch. Snags and down woody debris is common. American fly honeysuckle is the dominant shrub with leatherwood, Canada yew, and alternate-leaved dogwood also present. The ground flora is diverse. Grass and grass-like species include sedges, rattlesnake manna grass, and bottlebrush grass. Other herbaceous plants are club-moss, sessile-leaved bellwort, large-flowered trillium, rosy twisted stalk, dutchman’s breeches, mountain wood sorrel, and three-leaved goldthread. The flora of the gorge varies considerably from streamside to the adjacent ridge tops. The lowland areas and low, shaded cliffs are dominated by a canopy of white cedar, yellow birch, hemlock, and black ash. Canada yew and mountain maple are present in the midstory and on shaded cliff ledges. Ferns (especially Dryopteris) are abundant in the understory. Speckled alder dominates lower, wetter portions of the bank. In this region, the Brunsweiler River flows north through a series of natural, glacially-created lakes, with high gradients and deeply-cut chasms between the lakes. The erosive power of the river has created numerous streamside cliffs, both open and shaded, some of which harbor a large population of the rare fragrant fern. The cliffs also afford habitat to Braun’s holly fern. This stretch of river contains slack water, in the form of shallow pools, is interspersed with rapids flowing over large, granitic boulders. Two small, intermittent feeder streams, which drain the adjacent uplands, flow into the river from the east. A bridge crossing FR 187 spans the river and a footbridge for the North Country Trail crosses the river at the northern edge. The river itself is in natural condition, of high quality and supports a diverse fishery. Brunsweiler River and Mineral Lake is owned by the US Forest Service and was designated a State Natural Area in 2007.