Climate, Fire, and Land-Use History in the Oak-Pine-Hickory Forests of Northeast Texas during the past 3500 Years Climate, Fire, and Land-Use History in the Oak-Pine-Hickory Forests of Northeast Texas During the Past 3500 Years

Analyses of a palaeo-channel deposit in the valley of Big Sandy Creek in northeast Texas indicate that well preserved pollen of primary origin is encountered in high concentrations. Stratigraphic pollen data derived are employed towards a reconstruction of the history of the regional pine-hardwood forest from 3500 cal. BP until present. This bio-stratigraphic sequence demonstrates that the valley has remained almost completely under forest canopy during the Middle and Late Holocene, when it is comprised of a mixture of oak, pine, and hickory. During the past 3500 yrs, the relative importance of these taxa has also varied due to drought and fire. In this respect, a differential (riparian) representation by moisture-sensitive river birch in the pollen sequence strongly suggests that periodic droughts in the valley have caused a secular variation in fire frequency and magnitude. Finally, during the past 800 yrs (Caddo period), the first significant grasslands and forbs emerge in forest clearings.