The lush wetlands and thriving ferns of Cowles Bog form a primeval landscape unlike any other in the Indiana Dunes. A 4.7 mile-trail winds its way beneath the shady branches of black oaks, red maples, birches, tamarack pines, and white cedars. Cowles Bog sits at the foot of a steep sand dune, and the trail climbs dramatically before descending to the shore of Lake Michigan. The beach here is one of the most secluded in the Indiana Dunes, and it offers majestic views of the lake, the city of Chicago, and the mighty steel mills neighboring this natural treasure.
Cowles Bog is named for the scientist Henry Chandler Cowles from the University of Chicago. Cowles is one of the founders of the modern science of ecology, and a tireless champion of the dunes in the early twentieth century. Today Cowles Bog is home to over 400 species of plants, and countless varieties of mushroom and fungi. The National Audubon Society designated Cowles Bog an Important Bird Area, and the woods and wetlands here attract a stunning array of birds and waterfowl.
In 1953 Indiana Dunes champion Dorothy Buell and the newly formed Save the Dunes Council purchased the land in hopes it would one day serve as the foundation for a park. In many ways Cowles Bog is the heart of the Indiana Dunes.
The Geological Story of Cowles Bog
Like the rest of the Indiana Dunes, Cowles Bog’s story traces back to the last ice age, when advancing and retreating glaciers carved the landscape and left behind the massive sand dunes and wetlands. In spite of its names, Cowles Bog is scientifically a fen. Bogs, like nearby Pinhook Bog in the Indiana Dunes, are wetlands nourished only by rain or snowfall, resulting in stagnant water that is highly acidic. A fen, on the other hand, is more basic (with a higher pH level) and is fed by fresh groundwater. The combination of the fen, surrounding marsh, and trees makes Cowles Bog what is known as a “swamp complex,” and a vital wildlife habitat.
Marvelous Plants of Cowles Bog
A stunning array of plant life thrives at Cowles Bog beneath the branches of the variety of trees growing here. Nestled among the ferns, one can find carnivorous plants like the pitcher plants and sun-dew plants growing in the water. One of the most distinctive inhabitants of the area is the appropriately named skunk cabbage. This amazing plant can trap the heat of the groundwater, allowing it to flower even in colder winter temperatures. Finding pollinators in these conditions can be difficult, and so the skunk cabbage produces an unpleasant odor that attracts flies mistakenly in search of a meal.
Of course, these odiferous plants share space with a number of beautiful and much more pleasant-smelling wildflowers, as well. Native plants like the joe-pye weed and the white astors also flourish in the dunes. Along with milkweed and butterfly weeds, the abundant flowers make Cowles Bog an attractive spot for butterflies.
Visitors to Cowles Bog will immediately notice the waving cattails surrounding the fen. While they may look beautiful, only one species is native, and the other that grows here is invasive. Volunteers and park rangers work tirelessly to remove and control them to preserve this habit for the other species that call Cowles Bog hime.
Beautiful Birds of Cowles Bog
Like many locations in the Indiana Dunes, Cowles Bog has been designated an Important Bird Area by the Audubon Society. A number of beautiful birds and waterfowl can be found here, including the majestic sandhill crane and the Little Blue Heron. Among the reeds and cattails visitors can spot the American Bittern and marsh wren. The male marsh wren will build multiple nests that they may use throughout the year.
Cowles Bog is also an important habitat for the Virginia Rail, a marshbird considered endangered in the state of Indiana. These birds have a distinctive mating dance, complete with male displays of its wings and mutual bows back and forth.
Amazing Amphibians at Cowles Bog
The still waters and abundant plant life make Cowles Bog a perfect place for amphibians. The most distinctive resident is the four-toed salamander, which lays its eggs above the water on the thick stalks of grass and cattails. Unlike other salamanders living in Indiana, this is the only species that has just four toes on its back feet.
A short distance from the trailhead, Cowles Bog trail features a lovely raised boardwalk that allows visitors to walk above this incredible wetland.
In the spring, watch for pairs of Sandhill Cranes raising their newborns in the marsh just off Mineral Springs Road to the east and west.
The northern edge of the trail from the Main Lot takes you by beaver lodges that are right off the trail in the wetland to the south. Watch for them about a mile from the Main Lot.
Be the Change — Volunteer! Get more involved with the Indiana Dunes! There are many no-hassle, drop-in volunteer opportunities available for everyone. Just show up! The organization provides the gear and training.
While the Indiana Dunes area is considered a safe, family-friendly destination, there still some things you need to know. In this video, we explore different safety tips and visitor responsibilities. From understanding rip tides to protecting yourself against ticks, this video offers important information for keeping you and your loved ones safe during your stay in the Indiana Dunes area.
If you’re looking for a plethora of diverse wildflowers then park at the Greenbelt parking lot during the spring. Visitors will hike along an open landscape covered in flowers as they travel toward the main trailhead. Spring migration offers birders the opportunity to scout out a variety of birds as they rest in the trees at Cowles Bog before heading over Lake Michigan.
What to Expect
There are two parking lots available at Cowles Bog. For quick access to spring flowers, and ponds filled with Great Blue Herons, Canada Geese, and Capsian Terns, take a left after the railroad tracks on Mineral Springs Road and park in the paved Greenbelt Trailhead lot.
For the fastest route to the boardwalk viewing platform, enter the trailhead through the main parking lot which is located just before the Ogden Dunes town guardhouse.
The trail is a mixture of loose sand and packed dirt with moderate to rugged dune climbs. Visitors will hike along ponds, marshes, and black oak savannas, eventually leading to Lake Michigan.