This report summarizes up to 39 years of plant community development trends on Syncrude’s reclaimed mine sites near Fort McMurray, Alberta. These trends are contrasted with a target condition, defined here as the Natural Range of Variability for species composition on older (60+ yrs) closed canopy forests having similar mesic and sub-mesic site conditions within 200 km of the mine sites. The primary outcome of the study is that patterns of plant community change on reclaimed sites are consistent with Alberta’s objectives for reclamation, which require increasing similarity between reclaimed and reference plant community structure over time. Evidence is also provided demonstrating the strong influence of a developing tree canopy on these patterns, where native forest-dependent species gain an increasing competitive advantage over time as compared to early arriving ruderal or weedy species. Overall, it is concluded that expected natural processes, consistent with conventional ecological theory, are leading to reclaimed sites demonstrating substantial convergence with locally common boreal forest ecosystems.