Did you know that a tree’s age can be determined by counting its rings? Starting from a living tree, an overlapping, chronological sequence can be produced (for English oak this can be traced back more than 7000 years).
Cut timber also shows the ring pattern. This means that, provided the outer layers are present, wood from a building can be compared to the sequence and the date when the tree was felled can be calculated. Dendrochronology cannot tell how soon after this the wood was used for building, or whether it has been reused