The re-evaluation of INAI sites discovered between 1978 and 2007 began in late summer of 2008 and continued to early fall of 2011. A total of 664existing Category I Illinois Natural Areas Inventory (INAI)sites were identified in the original proposal for re-evaluation for this project. Through discussions and clarifications with the Illinois Department of Natural Resources (IDNR), this re-evaluation list was reduced to 648unique sites. Sites were also rejected for re-evaluation(10%)if communities in the initial listwere duplicated (extra listing or sites spanned twocountiesweredeleted), werenot vegetation-based communities,such as caves, open water, etc.(37 sites), railroad prairieswhere land owner contact would be denied(24 sties), or they were designated INAI sites after the project began(6 sites). Some sites(9%)were not visited if land owner contact information was not available(42), or access was denied(14). The remaining sites were divided into 3 groups, by geographical area, one group to be visited per field season. A total of 525(81%) sites were visited for this project.There are three key findings from this re-evaluation of INAI sites. First, Natural area management is essential to the continued existence of these sites. Natural areas that received moderateto intensive management maintained or improved their natural quality over time. Natural areas that did not receive management have degraded or vanished. Second, small, fragmented natural communities (e.g. hill prairies) and those subject to significant degradation from off-site factors (e.g. marshes, sedge meadows) are especially at risk of disappearing state-wide. And third, prescribed fire at remedial and maintenance regimes is critical to the long-term viability of most natural areas and communities in Illinois. Fire not only helps achieve more natural conditions on the sites, but also prevents degradation by invasive species –the #1 management threatto natural areas generally.
|Name||INHS Technical Report 2012 (36,37,38)|