Dating prehistoric bog-fires in northern England to calendar years by long-distance cross-matching of pine chronologies

The ages of prehistoric fires can be approximated by radiocarbon dating of charcoal or associated material, but such dating is often inaccurate and at best imprecise. Pine trunks preserved in British and Irish peats occasionally show firescars, which might be dated through dendrochronology to yield calendar‐year dates. However, unlike oak, there is no master pine chronology to provide absolute dates, so dating is dependent on interspecies cross‐matching; for sites in the British Isles with no dated oaks, calendar‐year dating of prehistoric pines has hitherto proved impossible. We present a first success in dating, accurately and precisely, prehistoric fire events recorded in subfossil bog‐pine trunks, using long‐distance cross‐matching of pine chronologies between White Moss, Cheshire, and the Humberhead Levels, England. Results demonstrate a bog‐fire in Cheshire in spring 2800 BC, and again in 2710 BC, between spring and summer. Further successful long‐distance cross‐matching of pine would permit international climatological comparisons. © 1997 John Wiley & Sons, Ltd.