This study was initiated to document forest development in the oldest natural area in the Ridge and Valley of east Tennessee. The Ijams Nature Reserve was established in 1910 and provided the opportunity to document secondary succession of the oldest upland forest reserve in the region. We established forest inventory plots in the original land holding of the Ijams family to quantify species composition, stand structure, and successional dynamics. We also analyzed the radial growth patterns of trees to document stand age, recruitment, and the disturbance regime of the reserve. The forest was dominated by Quercus alba and Liriodendron tulipifera while Acer saccharum and Fagus grandifolia had high densities in the understory. Liriodendron tulipifera was the most important species in the stand because it colonized the site following agricultural abandonment and subsequently established in small canopy gaps. The stand had a reverse J-shaped diameter structure typical of regenerating forests. The forest experienced one stand-wide disturbance event likely attributed to the decline of Castanea dentata in the 1920s. The return interval of stand-wide disturbances was much longer than what has been reported in other eastern hardwood forests. With the exception of this one stand-wide release, the disturbance regime was characterized by localized, asynchronous events that influenced only neighboring trees. Under the current disturbance regime, composition of the stand is projected to change as shade-tolerant mesophytes in the understory (A. saccharum and F. grandifolia) are recruited to larger size classes. This phenomenon has been widely reported throughout the eastern United States and is most commonly linked to active fire suppression. However, the forest of the Ijams Nature Reserve has not burned during development and still shows a marked change in species composition even with no change in the fire disturbance regime. We propose the composition shift is related to understory facilitation by disturbance oriented canopy species that have created conditions favorable for the establishment of mesophytes and by the loss of C. dentata that resulted in canopy gaps.
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