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A habitat monitoring program was initiated in 1991to mitigate long-standing conflicts concerning forage allocation among cattle, elk, and deer in southeastern British Columbia. The sites were re-sampled in 2009. The Skookumchuck Prairie Historical Exclosure was constructed in 1951 and was sampled at 10-year intervals between 1960 and 2009. In 1951, plant communities on both the grazed and ungrazed areas were dominated by early seral species. Inside the exclosure, the plant community advanced to a stand dominated by rough fescue (Festuca scabrella) and Idaho fescue (Festuca idahoensis), whereas the grazed area remained at an early seral stage. Bluebunch wheatgrass (Agropyron spicatum), which was virtually absent inside the exclosure in 1951, peaked in cover by 1970 and then declined from about 50% cover to less than 5% by 2009. Constructed in 1991, the Skookumchuck Prairie "Three-way Exclosure" Site was divided into three grazing treatments to allow differential access to cattle, wildlife, and cattle and wildlife together. An exclosure was constructed adjacent to the grazed areas. Early seral plant communities dominated all four areas in 1991. After 18 years, rough fescue and Idaho fescue cover had increased significantly in the Ungulate Exclosure and Cattle Only Area, but cover of these species remained negligible on the Wildlife Only and Combined Use Areas. Vegetation changes in both the grazed areas and ungrazed exclosures at Premier Ridge and Pickering Hills were stagnant for 18 years, indicating that historical grazing had impeded recovery. These exclosures demonstrate that rangelands can recover to higher seral stages given proper management and sufficient time. Plant communities resulting from such recovery, however, will contain a mix of native dominant species and naturalized alien species that may have reached a new “steady state” or “potential natural community.”  Long-term exclosures provide a rare opportunity to evaluate undisturbed plant communities over extended time periods.