Dendro-dating can be a very effective although not foolproof way of creating data that can often lead to discerning the age of construction of various buildings and structures in the northeast and beyond.
There are, however, certain criteria that must be satisfied or met in order that a wood testing on any particular building will yield good to even excellent but not guaranteed results.
Scientists and scholars of various disciplines have been using recent advances in dendrochronology, or tree-ring dating studies, in the Northeast along with the development of regional master chronologies for various species of trees to promote the dating of timber framed buildings and other buildings that have timbers somewhere in their construction.
Although the science of dendrochronology was first formulated about 1905, it has only until very recently, perhaps since 2000, that the science has gained much popularity with private homeowners.
Since the summers and winters of consecutive years are never completely the same, the rings of trees show an irregular pattern: thick and thin rings alternate with each other without any particular system.
This irregular pattern is expressed in a dendrochronological curve: along the vertical axis, we can plot the thickness of the ring, and along the horizontal axes, we can plot the years.
When a tree is felled, it is possible to count the growth rings, and because we know that a tree makes a new ring every year, we can establish in which year the tree was planted.
But although a tree makes a new ring every year, not every annual ring is the same.- Architectural heritage: trusses and timber framing; plank floorings, wainscotings and ceilings; staircases, windows, doors, cabinetwork, etc.- Archaeological heritage: remains of constructions (houses, bridges, ports, etc.); artefacts; boats; barrels, wells, etc.As archaeological dating techniques go, dendrochronology is extremely precise: if the growth rings in a wooden object are preserved and can be tied into an existing chronology, researchers can determine the precise calendar year--and often season--the tree was cut down to make it.Because of that precision, dendrochronology is used to calibrate radiocarbon dating, by giving science a measure of the atmospheric conditions which are known to cause radiocarbon dates to vary.Radiocarbon dates which have been corrected--or rather, calibrated--by comparison to dendrochronological records are designated by abbreviations such as cal BP, or calibrated years before the present.