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

Abstract

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.

Mid-Holocene pine woodland phases and mire development - significance of dendroecological data from subfossil trees from northwest Germany

“…The bog‐pine GDO phases are much shorter and the pine populations are more clearly delimited. Our results are in line with other dendrochronological studies of subfossil pines, although in these previous studies patterns were often less clear, mostly due to smaller sample sizes (Munaut 1966; Munaut & Casparie 1971; McNally & Doyle 1984; Chambers et al 1997; Pukienė 1997; Gunnarson 1999; Lageard et al 1999; Boswijk & Whitehouse 2002). Wave‐like regeneration patterns were also reported for pine populations from dry sites in northern Sweden (Zackrisson et al 1995).…”

“…Such subfossil pines ( Pinus sylvestris L.), in the following referred to as ‘bog‐pines’, usually occur in distinct stump layers within the peat and they testify to striking environmental changes that affected their mire habitat. Dendrochronological studies across Europe have demonstrated a huge potential of subfossil bog‐pines to serve as a high‐resolution archive of ecological changes (Munaut 1966; Munaut & Casparie 1971; McNally & Doyle 1984; Pilcher et al 1995; Chambers et al 1997; Pukienė 1997; Gunnarson 1999; Lageard et al 1999; Boswijk & Whitehouse 2002; Boswijk 2003). However, these investigations were generally quite local in extent and tended to include only a limited number of samples, and any ecological interpretation of their findings thus had to be confined to the local scale.…”

“…The only regionally representative investigations of subfossil pines were carried out by Birks (1975) and Bridge et al (1990) for Scotland and by Bennett (1984) for Britain and Ireland, but these studies did not apply dendrochronological methods. Dendrochronological dating of bog‐pine chronologies to calendar years was achieved in a few later studies carried out in Ireland (Pilcher et al 1995) and England (Chambers et al 1997; Boswijk 2003).…”

The 12,460-Year Hohenheim Oak and Pine Tree-Ring Chronology from Central Europe—A Unique Annual Record for Radiocarbon Calibration and Paleoenvironment Reconstructions

“…Both the high-frequency (year-to-year) correlation and the long-term trends agree remarkably well. The grade of uniformity of this interspecies cross-match is comparable to northern England subfossil pine and oak comparisons (Chambers et al 1997) and to cross-matches of modern oak and pine chronologies from southern Germany. Interestingly, the dendrochronological crossdating resulted in a difference of only 8 yr with respect to the published 14 C wiggle-match position used for IntCal98 (Kromer and Spurk 1998).…”

Climatic significance of the marginalization of Scots pine (Pinus sylvestris L.)c. 2500 BC at White Moss, south Cheshire, UK

“…More recently, the successful cross-matching of subfossil oak and pine records from the same site (Garry Bog) in the north of Ireland (Brown, 1991) has allowed previously floating pine chronologies to be assigned calendar ages. It has also been demonstrated that long-distance cross-matching of pine chronologies is attainable for sites in England (Chambers et al, 1997). This has allowed more accurate dating of pine occurrences on bogs, but has not addressed the reasons for the apparent 'pine decline' witnessed in many palaeoecological records throughout the British Isles c. 2500 cal.…”