Dendroarchaeology
Dendroarchaeology is a term used for the study of vegetation remains, old buildings, artifacts, furniture, art and musical instruments using the techniques of dendrochronology (tree-ring dating). It refers to dendrochronological research of wood from the past regardless of its current physical context (in or above the soil). This form of dating is the most accurate and precise absolute dating method available to archaeologists, as the last ring that grew is the first year the tree could have been incorporated into an archaeological structure. Tree-ring dating is useful in that it can contribute to chronometric, environmental, and behavioral archaeological research. The utility of tree-ring dating in an environmental sense is the most applicable of the three in today's world. Tree rings can be used to reconstruct numerous environmental variables such as temperature, precipitation, stream flow, drought society, fire frequency and intensity, insect infestation, atmospheric circulation patterns, among others. History At the beginning of the twentieth century, astronomer Andrew Ellicott Douglass first applied tree ring dating to prehistoric North American artifacts. Through applying dendrochronology (tree-ring dating), Douglass hoped for more expansive climate studies. Douglass theorized organic materials (trees and plant remains) could assist in visualizing past climates. Despite Dr. Douglass’s contributions, archaeology as a discipline did not begin applying tree-ring dating until 1970s with Dr. Edward Cook and Dr. Gordon Jacoby. In 1929, American Southwestern archaeologists had charted a non continuous historic and prehistoric chronologies for the Chaco Canyon Region. Tree ring laboratory scientists from Columbia University were some of the first to apply tree-ring dating to the colonial period, specifically architectural timbers in the eastern United States. For agencies like the National Park Service and other historical societies, Dr. Jacoby and Cook began dating historic structures in the lower Hudson River Valley, New Jersey and Eastern Pennsylvania. This was difficult at the time due to a lack of sufficiently long master dating chronology and access to suitable structures. Not until 1998 was a Boston area master dating chronology developed. Today, the effectiveness of tree ring laboratory archaeological dating chronologies covers most of the area that was settled by the first European colonists. The numbers of these are in the hundreds and include historically significant structures such as Independence Hall and the Tuckahoe estate. Methodology There are two types of dates that can be assigned to tree specimens: cutting dates, and noncutting dates. Which date is assigned to a specimen is dependent on whether or not there is evidence that the last ring present on the specimen was the last ring the tree grew before it died. Cutting dates can be used for crossdated tree specimens that "possess evidence that the last ring present on the specimen was the last ring grown by the tree before it died." Noncutting dates are used for crossdated tree specimens "if there is no evidence indicating that the last ring present on the specimen is the last one grown before the tree died." Patterns of tree growth will be similar between trees of the same species,