| Impact ID | 8993 |
| Impact Type | Competition |
| Study Type | Observational |
| Study Location | Field |
| Impact Description | In Gavin Bog, Illinois, Rhamnus frangula (glossy buckthorn) has displaced Ilex verticillata, a native species to the Great Lakes. |
| Reference | 25485 |
| Cost | |
| Location | Prairie Nature Preserve, Lake County, Illinois |