ENCOU R AGI NG A NE W G ENER AT ION OF OAK S
let the sun shine
At a glance, the woodlands of the South Des Plaines River (SDPR), appear healthy. However, data collected by District ecologists and other regional scientists show that oaks are aging, with few younger oaks in the understory to take their place. This pattern has been observed across the eastern United States. The oak has historically been revered as a symbol of strength in many cultures. In addition to being an iconic feature of the Lake County landscape, the mighty oak is a keystone species in the SDPR preserve ecosystems. Keystone species are species whose impact on its environment is disproportionately large relative to its abundance. Without oaks,
A SHIFT IN THE CANOPY Moderately moist (mesic) forest communities were historically associated with the Des Plaines River, supporting a diverse array of wildlife. Many species that were once common in more open, lightabundant woodland communities are uncommon or absent today due to changes in these habitats. Dense stands of trees that thrive in closed canopies have decreased diversity of ground-dwelling plants. Changes to water distribution and retention have caused a decline in many wildlife species, especially those that require seasonal ponds to breed.
necessary conditions for flowers and grasses, and food and habitat for wildlife would be lost. A 2009 study indicates a need for restoration focused specifically on increasing light availability in the SDPR preserves. Increased light would allow for the regeneration of oaks and other desirable species that prefer open canopy, in turn increasing biodiversity.
EASTERN SCREECH OWL AT RYERSON WOODS ST MARYS RD
SOUTH DE S PL AIN E S RIVE R PR E S E RVE S
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EVERETT RD
MACARTHUR WOODS
GRAINGER WOODS CONSERVATION PRESERVE
CAPTAIN DANIEL WRIGHT WOODS
RYERSON CONSERVATION AREA
CAHOKIA FLATWOODS
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WATER
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DES PLAINES RIVER TRAIL
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Located in southeast Lake County, the 22
Southern Des Plaines River (SDPR) preserves include MacArthur Woods, Grainger Woods, Wright Woods, Ryerson Woods, and Cahokia Flatwoods. These preserves represent some
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of the highest quality natural areas within RW
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Lake County. DS
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DEERFIELD RD
21 LAK E COUNTY FOR E ST PRE S E RVES LAKE COOK RD
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