Dendrochronology

Dendrochronology is a dating method based on the study of tree rings. Its name comes from the Greek words dendron ("tree"), chronos ("time"), and logos ("study").

How trees grow… =======================================================================================================================================

As a tree grows, it becomes taller… and wider. It is this radial growth that interests experts. At our latitudes, trees produce one ring (or growth ring) each year, forming beneath the bark. Examining these rings under a microscope reveals that they consist of cells of different sizes. In the part of the trunk closest to the bark, known as the cambium, these wood cells are alive and play a vital role. Minerals and water travel through them from the roots to the leaves and needles, rather like through giant drinking straws. In spring, the cambium produces large, thin-walled cells that enable the tree to feed and grow. Light in color, they form the part of the ring known as earlywood. Toward the end of summer, the tree's growth slows, and the wood cells it produces are smaller, with thicker walls. This darker part of the ring is called latewood. In winter, when the ground is frozen, the tree can no longer draw nutrients from the soil. It stops producing new cells and lies dormant until the following spring.