Chicago Botanic Garden

River Ecosystems

Once a meandering stream that was part of a larger complex of marsh, sedge meadow and wet prairie, in the early 1900s the Skokie River became a drainage ditch. Though no longer able to function as they once did, highly-engineered waterways like the Skokie River often remain valuable natural resources. A Chicago Botanic Garden project seeks to enhance part of the stream channel that flows through the Garden’s western perimeter: to develop habitat, increase biodiversity and improve water quality, while at the same time showcasing river enhancement techniques and serving as a living laboratory to study human-built riparian corridors. Twenty-two acres adjacent to the river have been devoted to this effort.

PHOTO: river algae Portions of eroded stream banks have been bolstered with woody plants. Along the river, floodplain wetlands, upland prairie and oak savanna-woodland also are being established. Approximately 200 species of native herbaceous plants are thriving. Fast-growing species, along with remnant Garden horticulture, form a backdrop on the Garden’s western edge as slow-growing oaks—primarily burr oak (Quercus macrocarpa)—reach maturity. Reed canary grass (Phalarus arundinaceae) is an invasive species that presents one of the greatest challenges to developing a native floodplain plant community. Despite aggressive efforts at elimination and establishment of native sedges, grasses and forbs, reed canary grass, with its tolerance of both prolonged flooding and drought conditions, is again gaining dominance in much of the floodplain. Garden scientists continue to explore and study methods for reversing this trend.

Compacted, engineered soils challenge the establishment of native plants in the uplands of the river corridor as they do in the development of the Dixon Prairie, and Garden scientists are studying the river to determine how soil disturbance can affect our ability to create native grassland communities.