Do historic log buildings provide evidence of reforestation following depopulation of Indigenous Peoples?

Abstract

AbstractAimTo test the previously published hypothesis that there was widespread reforestation following the depopulation of Indigenous Peoples in the 16th and 17th centuries.LocationThe central Appalachian Mountains of eastern North America.TaxonQuercus alba, Liriondendron tulipiferaMethodsTo test for reforestation following depopulation, we used tree‐ring evidence of tree recruitment, early radial growth and growth releases from 18 historic log buildings (n = 361 logs) and eight old‐growth forest sites (n = 197 trees). We used inner‐ring dates to determine if a synchronous recruitment event(s) was present at historic sites but absent from old‐growth sites following depopulation. We used cluster analysis to determine if historic logs established in a clearing (fast early growth) or under a canopy (slow early growth). Similarly, we calculated disturbance rates (growth releases per 100 years) to determine if historic logs grew in a clearing (low disturbance) or under a canopy (high disturbance).ResultsHistoric log and old‐growth forest sites both document a period of elevated recruitment beginning in the 1670s. This event was observed in previous studies and across site types, suggesting that either climate variability or the absence of low‐intensity land use (e.g. fire) may have also contributed to forest establishment. Most historic sites (61%–83%) had fast early growth, indicating growth of trees in high‐light conditions. The rate of disturbance was lower at historic sites with fast early growth (5.3 events/century, 95% Cl [3.6, 7.0]) than at old‐growth sites with slow early growth (23.5 events/century, 95% Cl [17.5, 29.5]), consistent with the idea that most historic logs were harvested from fast‐growing, second‐growth forests that established after depopulation.Main ConclusionsOur results support the hypothesis of reforestation in upland forests of the central Appalachian Mountains following depopulation and suggest that upland forests, at the time of European immigration, were at least in part, a legacy of indigenous land use practices. However, the timing of a regional drought event, depopulation and subsequent recruitment of trees, all within the period of ~1650–1690 CE, warrants further research into interactions between indigenous land use and climate during a pivotal period in North American history.