After turning north-by-northeast where the Boone River met the Des Moines, the 1835 Iowa Dragoons Expedition crossed a series of prairies and watersheds as they advanced toward the Dakota leader Winona’s village in modern-day Minnesota. Bodies of water marked their progress, first Clear Lake before the course meandered across the Winnebago River (then Lime Creek) just south of Portland, Iowa.
Today, Highway-122 paves the way east of Mason City near where the blooming prairies unfolded before the plodding column of horses and wagons back in 1835. Lea noted: “Nothing peculiar presents itself between Otter Creek (Today: West Fork, Cedar River) and English (Shellrock Rock), or rather the Lime Creek branch, where large groves relieve the general baldness of the prairie.” (Lea Journal). As the expedition moved through the area, further notes indicated large numbers of bison throughout the area. In contrast, modern sojourners might come across a solitary American Bison sunning itself near the Shell Rock River in an enclosure on the edge of Nora Springs, a remnant reminder of Iowa’s ever-changing environmental past. Nora Springs continues to celebrate the history of bison in the area, hosting Buffalo Days each June.
Just to the south of Nora Springs, not far from where the Shell Rock meets the Winnebago to join their travels on their way to the Cedar River, remnants of an even deeper environmental past linger in the Claybanks Forest and the Limestone Prairie Preserve. Fossils from the Devonian Period still find exposure on the soft limey shales and limestone throughout the preserves. The 375-million-year-old remnants of ancient aquatic life make up the type-locality of the Lime Creek Formation.
The Lime Creek Formation contains three parts: Juniper Hill, Cerro Gordo, and Owen. The latter two portions are contained within the Claybanks Forest and Bird Hill locations. In the past, the Claybanks Forest found local designation as Hackberry Grove, a lineage also providing the designation of Hackberry Fauna to specific fossils found at the location. Eager hunters today can find brachiopods, gastropod molds, horn corals, colonial corals, stromatoporoids, bryozoans, echinoderm debris, crinoids, cephalopods, trilobites, pelecypods, and other microscopic vertebrates at the sites.
Lea also noted the area containing “a tract diversified with woods & prairie, hill and dale…” (Lea Journal). When Albert M. Lea and his company made their way through the area, stands of Oak and Cottonwoods crowded the shores of the Lime Creek. Today, in the Claybanks Forest’s more westerly segment, similar visitas still meet the casual observer. Roughly 56-acres of predominantly Basswood and Maple compose the modern Claybanks Forest, a contrast to the types of trees observed by Albert Lea .In the early spring wildflowers still dot the forest floor, developing in stages reliant on sunlight exposure and seasonable temperatures.
In the easterly unit of the forest, the namesake slimy shores of the area gather the tracks of waterfowl and other forest dwellers. “All of these rivers, creeks, and lakes, are skirted by woods, often several miles in width, affording shelter from intense cold or heat to the animals that may take refuge from the contiguous prairies. These woods also afford the timber necessary for building houses, fences, and boats,” wrote Albert Lea in his 1836 work Notes on the Wisconsin Territory. Evidence of wildlife also lingers along the shores of the river. Modern observers can easily spot a deer crashing through the undergrowth, spot the deep impressions left by waterfowl on the banks of the river, or send small frogs springing into the waters of the Winnebago.
A stretch further south, Zinnia Ave. turns to the west, and a revitalized prairie stands to the south. Lea noted the prevalence of prairies throughout the region often in his Notes on the Wisconsin Territory: “The general appearance of the country is one of great beauty. It may be represented as one grand rolling prairie, along one side of which flows the mightiest river in the world, and through which numerous navigable streams pursue their devious way towards the ocean.” The prairie stretches north beyond the road to a defunct limestone quarry. Although the quarry disrupted the ecological timeline of the site, many wet and dry plant communities still occupy the site today. Grey-headed Coneflower, Pale Purple Coneflower, Little Bluestem, and Sideoats Grama still persist along the trail circling the quarry pond. The exposed limestone of the quarry scars expose more Devonian fossils.
Although the environment surrounding the Winnebago River changed from the tile of Albert Lea and the Dragoons passed through the area in 1835, modern observers can still find ready reminders of Iowa’s geological and ecological past in the lands still preserved today.