Dating of events from tree growth and wood structure totally maried dating sites
New growth in trees occurs in a layer of cells near the bark.
A tree's growth rate changes in a predictable pattern throughout the year in response to seasonal climate changes, resulting in visible growth rings.
During the first half of the twentieth century, the astronomer A. Douglass founded the Laboratory of Tree-Ring Research at the University of Arizona.
Douglass sought to better understand cycles of sunspot activity and reasoned that changes in solar activity would affect climate patterns on earth, which would subsequently be recorded by tree-ring growth patterns (i.e., sunspots → climate → tree rings).
Diagram of secondary growth in a tree showing idealised vertical and horizontal sections, a new layer of wood is added in each growing season, thickening the stem, existing branches and roots, to form a growth ring Horizontal cross sections cut through the trunk of a tree can reveal growth rings, also referred to as tree rings or annual rings.
Growth rings result from new growth in the vascular cambium, a layer of cells near the bark that botanists classify as a lateral meristem; this growth in diameter is known as secondary growth.
Each ring marks a complete cycle of seasons, or one year, in the tree's life.
It is also used as a check in radiocarbon dating to calibrate radiocarbon ages.Dendrochronology (or tree-ring dating) is the scientific method of dating tree rings (also called growth rings) to the exact year they were formed.As well as dating them this can give data for dendroclimatology, the study of climate and atmospheric conditions during different periods in history from wood.During the latter half of the nineteenth century, the scientific study of tree rings and the application of dendrochronology began.In 1859, the German-American Jacob Kuechler (1823–1893) used crossdating to examine oaks (Quercus stellata) in order to study the record of climate in western Texas.