Structure, history and dynamics of a mature oak-beech forest in western Indiana

This study relates contemporary patterns of species composition, stand structure, and tree regeneration in a mature western Indiana forest, Kieweg Woods, to the complex of Euro-American settlement impacts and regional environmental change. We established permanent plots at this 5 ha flat upland site to initiate a long-term program of forest monitoring; this paper reports on the results of the first stand census, as well as placing them in historical context by examining both General Land Office survey records for the surrounding landscape and the dendrochronology of several of the stand's mature trees. Reconstruction of presettlement vegetation indicates that this site was transitional between open Quercus-Carya assemblages found at the margins of prairie and the more mesophytic Fagus grandifolia-Acer saccharum forests associated with the dissected topography of the Wabash River valley. Contemporary stand composition reflects this mix of species, but with Quercus spp., Carya spp. and Liriodendron tulipifera dominating the canopy and Acer saccharum and Fagus grandifolia comprising most of the subcanopy. Dendrochronological analysis indicates that the largely shade-intolerant canopy members were recruited during a major growth release in the late nineteenth century, probably due to logging, while the subcanopy has formed under a regime of minimal disturbance. These patterns suggest an impending successional turnover in canopy composition, and highlight the role of settlement impacts in remnant forests as having altered the presettlement linkages among disturbance and site conditions, and thereby reformulated the set of species' life history characteristics best suited to dominance in the contemporary landscape.