Many Groups Help Restore Indiana's Unique Cowles Bog

With a grant from the National Fish and Wildlife Foundation, Indiana Dunes National Lakeshore (IDNL) is partnering with community groups to restore the Cowles Bog wetland complex. Once home to the northern bog orchid, white lady's slipper, and moccasin flower, this historic site has suffered from landscape alterations, fire suppression, and other human pressures.

"Over the past 18 years, shrubs, hybrid cattail, and common reed have expanded throughout the complex," states Daniel Mason, IDNL botanist. "In 1938 there were almost 124 acres of sedge meadow; today, less than 2.5 acres remain."

Cowles Bog, a National Natural Landmark named in honor of Professor Henry Chandler Cowles, the University of Chicago professor whose studies helped establish ecology as a science, is actually a mosaic of marsh, forest, and graminoid fen in the westernmost part of the Great Marsh at IDNL (CW, Fall 1998). Indiana's only native white cedar population is found here, but deer browsing has limited cedar reproduction. As part of the restoration project, the Friends of Indiana Dunes have helped propagate white cedars from collected cuttings. Sixteen potted cedars were transplanted within a deer exclosure last fall; another ten will be planted this spring.

Over the past two years, volunteers from the Northwest Indiana Chapter of The Nature Conservancy have applied herbicide to cattails on a portion of Cowles Bog known as The Mound, as well as surrounding wetlands. North Judson High School volunteers and Boy Scout Troop 928 have removed shrubs there. Last growing season, native forbs recolonized the edge of The Mound, but hybrid cattail, a cross-breed of the native broad-leaved cattail and nonnative narrow-leaved cattail, began to reinvade.

"On the center of The Mound, however, a number of natives have reestablished themselves, including fen thistle, blue joint and fowl manna grasses, and porcupine sedge," Mason reported. "We have learned that herbicide can be applied to cattail with little collateral damage to understory plants, but areas with no understory will be recolonized by cattail."

Last fall, Student Conservation Association volunteers, park technicians, and many other helpers added more than 4,000 plants at Cowles Bog. Almost half of these are tussock sedge that were donated by Marshland Transplant Aquatic Nursery of Berlin, Wisconsin. IDNL grew the rest of the plants, among them water and lake sedge, marsh milkweed, and blue flag, at their greenhouse.

The IDNL team also germinated seeds collected from The Mound's seedbank and transplanted seedlings including the state-endangered small forget-me-not and state-threatened long-beaked bald rush. "Since few perennial species were present in the seedbank," Mason explains, "reestablishing Cowles Bog's biodiversity will require seed collection from nearby wetlands and greenhouse propagation."

IDNL estimates it could take 15 to 20 years and cost nearly two million dollars to complete the restoration project.