Hardwood Swamp Restoration Phase 1
Characterized by seasonally high-water tables that usually dry out by late summer, our four-acre Hardwood Swamp Project area was an ideal location to restore this important, rare, and diverse wetland community. The first phase was completed in 2022.
The Significance of the Hardwood Swamp
Hardwood swamp habitat was uncommon in this region, even prior to European settlement. Today less than 1% of natural areas in southeastern Wisconsin can be classified as this habitat type. Part of Schlitz Audubon’s Management Plan is to conserve and restore wildlife populations of greatest conservation need, so as a rare habitat, the southern hardwood swamp performs a very important ecological role.
This area is located between Brown Deer Road and the West Meadows Loop, and for many years most visitors would likely have overlooked it. The Center used to be a working farm, and an old agricultural drainage ditch still bisects the landscape here. Colonization by highly invasive reed canary grass and the loss of three ash tree species due to emerald ash borer made restoration of this hardwood swamp regionally significant.
Starting Phase 1
Schlitz Audubon staff and volunteer land stewards had already been removing invasive shrubs and herbaceous species and felling hazardous ash trees from this location of the property. Then in fall 2020, major support es from the U.S. Fish & Wildlife Service and gifts from individual donors allowed our volunteers and staff began the first phase of the Hardwood Swamp Project.
The first task was removing the remaining stands of invasive species, including buckthorn and reed canary grass. Next came planting 250 shrubs, such as silky dogwood, winterberry, and nannyberry. Tree installation included 715 trees partial to wetter habitats, such as swamp white oak and American sycamore. In a later part of phase one, 24,500 herbaceous plugs including native wildflowers, such as wild bergamot and black-eyed Susan, were planted in the project area.
Benefits and Ecological Importance
Hardwood swamps and other wetlands benefit many species that are experiencing population decline due to habitat loss. Structurally diverse, hardwood swamps contain numerous microhabitats that a variety of species depend upon. The restoration of this habitat provided a rich landscape for these species to thrive.
The habitat provides food, cover and breeding habitat for migratory birds, including Pine Warbler, Wood Thrush, American Woodcock, and Northern Flicker. The increased amount of time the swamp retains moisture will create essential spring stopover habitat for Canada Warbler, Blue-winged Teal, Wood Duck, and many additional species of greatest conservation need. Bird species like Golden-winged Warbler favor understory thickets typical of a swamp, utilizing the cover and plentiful insects they provide. Hardwood swamp is also specifically associated with locally rare bird species such as Rusty Blackbird, Yellow-billed Cuckoo, and Yellow-crowned Night Heron—a species not yet recorded at Schlitz Audubon.
The restored understory will support many pollinator species, including the federally endangered rusty patched bumble bee and monarch butterfly. Other species associated with hardwood swamp that are of particular conservation interest at the Center include Blanding’s turtle and northern long-eared bat.
The maturing southern hardwood swamp will continue to attract an increasing diversity of species for decades. It will offer a valuable learning platform to teach visitors about this rare habitat and its rich species composition and serve as an example for future conservation projects.