Kettle Moraine Red Oaks

State Natural Area (No. 259)

Location: Within the Northern Unit of the Kettle Moraine State Forest, Sheboygan County. T15N-R20E, Section 14. 316 acres.

Access: From the intersection of County Highways T and A in Greenbush, go south on A 1 mile to a pull-off on the east side of the road. The Ice Age Trail, which crosses A 0.2 miles farther south, traverses the site. Access also from the east along Ridge Road, 1.4 miles north of Highway Z.

Description: Kettle Moraine Red Oaks is a mature second-growth southern dry-mesic forest which originated in 1889. Composed of red oak, basswood, sugar maple and white ash, it is one of the richest oak forests in the region and contains over 100 species of trees, shrubs, and herbs. Other canopy species present include big-tooth aspen, white oak, black cherry, and shagbark hickory while the subcanopy is composed of ironwood, sugar maple, basswood, and ash saplings. The forest is situated on the high interlobate moraine and contains several outstanding dry kettle holes, which provide some diversity in exposure. The groundlayer contains characteristic dry-mesic species with three species of bedstraw, numerous sedges, downy Solomon’s seal, mayapple, maidenhair fern, American squaw-root, large-flowered trillium, sweet cicely, and Canada mayflower. This large tract provides important habitat for forest interior birds including three state-threatened species: Acadian flycatcher (Empidonax virescens), red-shouldered hawk (Buteo lineatus), and cerulean warbler (Dendroica cerulea). Other birds include ovenbird, barred owl, and wood thrush, wood pewee, and scarlet tanager. Kettle Moraine Red Oaks is part of the most extensive hardwood forest located within the region and forms the core of a larger proposed Habitat Preservation Area. Protection of this site is vital given the harvest pressure and the loss of red oaks across the landscape. As this site ages, it will become a prime candidate for research on old-growth red oak forests. Kettle Moraine Red Oaks is owned by the DNR and was designated a State Natural Area in 1992.