Restoring Grassland Habitat in Linn, Wisconsin

In 2000, local resident Melita Grunow donated 65 ha to the Town of Linn to establish a nature park, which is currently held in a conservation easement with the Geneva Lake Conservancy and sits between the tourist towns of Lake Geneva and Fontana, Wisconsin. The park boasts 62 ha of grassland, wetland, and savanna habitat in a gently rolling landscape. The 2 ha of active recreation facilities include a pavilion, picnic tables, playground equipment, and unique twin silos, built in the late 1880s, that have been restored (Figure 1).

The Town of Linn is located 40 km northwest of Chicago and 28 km west of Milwaukee and includes the north and south shores of Geneva Lake, one of the most important natural and economic resources in southern Wisconsin. Formed about 10,000 years ago, the lake is well known for its deep, clear water. A perpetual easement allows a continuous 33 km lakeshore-walking path to exist completely around Geneva Lake. The lake provides recreational opportunities, wildlife habitat, tourism opportunities, and aesthetic value to the area and to visitors. Geneva Lake is 2,130 ha with a maximum depth of 41 m. It is classified as a spring-fed lake, and its primary source is groundwater. The general land use pattern in the Town of Linn is residential lakeshore development adjacent to productive farmland. Over the years, the town and its residents have created a compact residential area along the lake, preserved farmland, and prevented the sprawl of tourist-oriented development along highways.

The Community Nature Park offers nature-based recreation opportunities. It is a unique habitat for many grassland birds of special concern. However, it was overgrown with common buckthorn (Rhamnus cathartica), box elder (Acer negundo), honeysuckle (Lonicera spp.), and other undesirable woody species. In 2002, the Town of Linn called the U.S. Fish and Wildlife Service (FWS) to take a look at the park and its inhabitants. Local birdwatchers had documented some very important birds during these years, including Henslow's sparrow (Ammodramus henslowii) and eastern meadowlark (Sturnella magna).

The FWS restored the hydrology by breaking drain tiles, dredging, and excavating to create two wetland areas in the center of the park and two ponds. The FWS also seeded 5 ha of tallgrass prairie with Indian grass (Sorghastrum nutans), big bluestem (Andropogon gerardii), compass plant (Silphium laciniatum), pale purple coneflower (Echinacea pallida), and rattlesnake master (Eryngium yuccifolium).

In the fall of 2007, the Town of Linn park committee contacted project ecologist Chris Kaplan from Tallgrass Restoration. Chris spent some time with the park committee, educating them on the types of natural communities they were managing. A ten-year management plan was created that the Town of Linn Board of Supervisors adopted in October 2007. The plan has two primary management goals: restore the natural communities of the park to benefit grassland birds, and improve the park's passive recreational amenities.

Figure 1.

The entrance to the Town of Linn Nature Park. Note the restored historic silos in the background.

Photo courtesy of Tallgrass Restoration

Tallgrass Restoration has cleared 40 ha of undesirable woody vegetation using a forestry mower for the smaller, scattered brush and chainsaws for the larger trees (Figure 2). An herbicide application of triclopyr in bark oil was applied to the stumps to prevent resprouts. Prescribed burning has occurred periodically on 36 ha of the grasslands to stimulate new growth and prevent resprouts of woody vegetation. The brushpile scars and larger cleared areas were seeded with a short grass, high-diversity seed mix. The site is monitored and resprouts are treated with metsulfuron methyl.

In addition, honeysuckle and other invasive species were removed from the bank of a small stream that meanders through the park. This was an enhancement project on a small remnant wet prairie. Once the invasive plants were removed, a native wet prairie seed mix was installed with an erosion control blanket. The installation is now in its second year and supports populations of prairie cordgrass (Spartina pectinata), great blue lobelia (Lobelia siphilitica), marsh thistle (Cirsium palustre), and spotted Joe-Pye-weed...