Morning light illuminates emerging ostrich ferns at Interstate Lowland Forest in Polk County.
Interstate Lowland Forest State Natural Area
Notable: The natural area features a mature southern wet forest community on what is periodically an island in the St. Croix River. During periods of high river levels, an old channel on the area’s north side fills with water and isolates the site. The canopy is composed of large silver maples with scattered black and green ash, hackberry and ironwood. Canopy openings resulting from Dutch elm disease are now filled with a dense growth of ostrich fern and nettles. The topography is irregular, with many linear levees and wet depressions created by periodic flooding. The rare Assiniboine sedge (Carex assiniboinensis) occurs here. Many birds nest in the forest, including eastern wood pewee, brown creeper, red-eyed vireo, indigo bunting and blue-gray gnatcatcher, along with two state-threatened species – red-shouldered hawk and cerulean warbler.
How to get there: Within Interstate State Park. From the junction of Highway 8 and Highway 35 in St. Croix Falls, go south on 35 a quarter-mile to the park entrance. Park maps are available at the visitor center. Follow the park road to the Camp Interstate picnic shelter parking lot. Take the Quarry and Point cross-country ski trails southwest into the natural area. See Interstate Lowland Forest for more information.