The lower portion of the Sugar River is home to several significant natural areas, including the Sugar River Alder Forest Preserve, the Colored Sands Forest Preserve, and the Sugar River Forest Preseve. The following excerpt on the Colored Sands Forest Preserve is taken from the Guide to Natural Areas in Northern Illinois, and the Winnebago County Forest Preserve District website.
We invite you to explore this diverse, beautiful, and important preserved area on the Sugar River. Shortly after the Sugar River exits the Sugar River Forest Preseve, it joins the Pecatonica on its journey to the Mississippi River.
Colored Sands Forest Preserve
Colored Sands is a 303.9-acre preserve that contains a dedicated Illinois Nature Preserve, the Sand Bluff Bird Observatory, and a restored sand prairie. The Nature Preserve in the southern third protects several unique habitats and harbors several Illinois endangered and threatened plant and animal species. The Sand Bluff Bird Observatory is one of the largest small-bird banding facilities in the country. Hiking trails provide access to the preserve and to the river for fishing.
Colored Sands Forest Preserve is named for the St. Peters sandstone found on the southern end of the preserve. The iron oxide in the stone darkens when it is exposed to the weather, creating magnificent colors. In midspring to midsummer, in the sandy open woodlands, you have the opportunity to see a spectacular display of wild lupine with beautiful, elongated blue flower clusters at the tops of the stems.
Visit the Sand Bluff Bird Observatory
Birds find an array of habitats in the prairies, low marshy areas, steep sand bluff, and bottomland forest. Nearly every migrating or nesting warbler, wren, vireo, sparrow, thrush, blackbird, and hawk recorded in Winnebago County has been found in the fields and woods of the extensive property. The Sand Bluff Bird Observatory, established in 1967, is the largest banding station in the Mississippi Flyway and one of the few banding stations open to the public. It monitors bird populations through bird banding on facilities furnished and maintained by the Winnebago County Forest Preserve District.
Explore the Unique Sand Prairie
Within the forest preserve is the 55-acre Colored Sands Bluff Nature Preserve. This area features bluffs on the Sugar River, dry sand savanna, dry dolomite prairie, and dry sand prairie. The nature preserve is home to unusual reptiles and amphibians, including fox snake, milk snake, western hognose snake, Blanding’s turtle, and the uncommon blue-spotted salamander.