This IBA, encompassing the Northern Unit of the Kettle Moraine State Forest, features a landscape rich in diverse glacial landforms such as kettle, kames, eskers, and outwash plains. The forests here are the most extensive in southeastern Wisconsin and are composed of oaks, hickory, basswood, sugar maple, and beech. Outwash plains are vegetated with swamp hardwoods, bog relicts, sedge meadows, small cattail marshes, and shrub carr. There also are conifer plantations and small areas of planted prairie.
This site harbors one of the core population areas for priority southern forest birds such as Eastern wood-pewee, Acadian flycatcher, wood thrush, cerulean warbler, and hooded warbler. Bogs and native and planted conifers host species more typical of northern Wisconsin such as Nashville warbler, pine warbler, Northern waterthrush, Canada warbler, and white-throated sparrow. Grass-shrub habitats contain Northern harrier, willow flycatcher, brown thrasher, and field sparrow. This IBA also is a significant concentration area for migrating landbirds in both spring and fall.