Dendrochronological research on archeological and living wood in the park holds the potential to more accurately date building construction phases and provide insights into climate changes and human adaptation to these changes.
Since 2006, I have been involved in an archeological tree-ring dating program that focuses on collecting samples from some of the last datable beams remaining in the park. The first goals is to ensure that all previously collected but unanalyzed tree-ring specimens collected at Mesa Verde NP have been analyzed and, hopefully, dated by specialists at the Laboratory of Tree-Ring Research (LTTR), University of Arizona.
It is also possibly the easiest for the lay person to understand since it depends on seasonal variations in the past producing recognisable patterns of tree growth which can be measured in wood found in archaeological contexts.
Each growing season, trees produce a new layer of wood under the bark; this varies in width slightly depending on the climatic conditions that year and this proportional width will be shared by all trees of the same species within that climatic zone.
In well-preserved samples, the date of felling can be refined to within a season of a particular year.
In addition to the five well known Mesa Verde cliff dwellings that are open to the public (Balcony House, Long House, and Step House on Wetherill Mesa; Cliff Palace and Spruce Tree House on Chapin Mesa), there are nearly 600 documented cliff sites within the park boundaries, ranging from small masonry granaries, to large cliff 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.Of these, roughly 250 are known to contain wood, but only about one tenth (24) of those contain wood from secure contexts that are likely to be datable.The other sites contain lintels, wall pegs, or loose wood specimens that are of the wrong species or who are too small to be datable. 1274, leaving a small but significant gap created, in part, by ring growth anomalies caused by the “Great Drought” (Douglass 1929).Tree-ring dating, or dendrochronology, has been an integral part of archeological research at Mesa Verde National Park (NP) since 1923, when members of the National Geographic Society’s First Beam Expedition collected samples from Cliff Palace, Spruce Tree House, and other sites (Douglass 1929, 1942; Nash 1999; Nichols 1963; Smiley 1947).The full dendrochornological potential of the park, however, has not yet been tapped.This paper reviews a sample of recent contributions to tree-ring method, theory, and data, and makes some suggestions for future lines of research.If you are on a personal connection, like at home, you can run an anti-virus scan on your device to make sure it is not infected with malware.Typically, a bachelor's degree in any of the above disciplines are enough to study the data that comes out of dendrochronology.Trees are a ubiquitous form of plant life on planet Earth.