EDO7851 - Tree-ring analysis of the timbers from the foundry site, Poole; analysis 1990

Jennifer Hillam conducted a dendrochronologic analysis of seventeen timber samples from the Foundry site (PM46) at the Sheffield dendrochronology laboratory. All came from boat timbers wich had been sealed by a reclaimation layer dating to 16th century and believed to have been deposited at about the same time. Associated pottery suggested that the timbers could be 15th century in date. These samples came from four keels, six piles and seven other boat timbers. The samples were frozen for at least 48 hours before their cross-sections were prepared using a Surform plane. Upon thawing the growth rings becane visible as did the structure detailing. At this stage identification of the wood type was possible as all the timbers had porous rings. This meant a rough ring count could be made, though any samples with a ring count of less that 40 was discarded as it would be unlikely to have a unique analysis. The ring widths of the remaining samples were measured with a travelling stage and the ring sequences were plotted as graphs. To indicate contemporanily the samples were compared. Three of the keels, one pile and two long timbers were identified as oak. The remaining keel, piles B-F, rough-outs and knee were oak. Further results of the analysis shows that the trees were grown in favourable conditions and were unlikely to be over 60-70 years old.