The Göttingen tree-ring chronologies of peat-preserved oaks and pines from Northwest Germany

To date, the tree-ring chronology of peat-preserved pines from Northwest Germany (Fig. 1) spans from 6703 BC to 1166 BC, but still contains two gaps. It was dated with the help of the previously constructed bog-oak chronology of Northwest Germany, the older part of which in turn has been dated using the pine chronology (Fig. 2), now covering from 6628 to 6178 BC additional to the previous span of 6069 BC to 931 AD. Compared to the oaks, chronology construction required large numbers of samples of the short-lived pine trees, many of which remained undated or dated relatively only. The dendrochronological process, which at times delivered a multitude of floating chronology fragments, was complemented by a number of radiocarbon dates. Preceding and following the calendar-dated pine chronology, there are radiocarbon dated floating chronologies. This pine record partly dates back to the beginning of the 9th millennium BC and documents environmental conditions during the early Holocene. It also shows the potential of the chronology to be extended further into the past. The Northwest German pine chronology has since been the base for dating i.a. archaeological finds, such as Neolithic wooden bog trackways. Moreover, the peat-preserved pines have proved to be valuable in palaeoenvironmental research, as they grew at sites where they were sensitive to hydrological changes. Particularly the climate-related advances of raised bog are well reflected in the material.