Fish Lake Sweet Fern Traditional Cache

Fish Lake is part of the Northwest Wisconsin Pine Barrens. The "Barrens" extends from northern Polk County to southern Bayfield County and covers 1,500 square miles. This large sand plain is a result of a large glacial lake (Glacial Lake Grantsburg) that covered the area after the retreat of the last glacier 12,000 years ago. The southern portion of the barrens, where Fish Lake is located, contains huge sedge marshes. These vast marshes are remnants of the glacial lake.

The sandy uplands of the wildlife area were historically covered by a jack pine savannah or brush prairie. The vegetation consisted of large jack and red pine widely scattered throughout an open expense of prairie grasses and wildflowers and a variety of woody vegetation including sweet fern, hazel, willow, blueberry and oak brush. The plant community was maintained by naturally occurring wildfires that frequently swept through the area.