Tree rings: The art and age of nature
The UA has plenty of special features to offer, but one of its more overlooked aspects is its abundant plant life—specifically, that of the Laboratory of Tree-ring Research.
UA’s tree-ring lab right is one of the best in the country, and the only only one located throughout the entire southwest, at that.
“This is the biggest and most diverse lab in the country,” said Ronald Towner, Ph.D., associate professor of anthropology. “We do a tremendous range of activity in this lab revolving around trees. Most other labs in the Western Hemisphere were started here.”
The lab studies dendrochronology, otherwise known as tree-dating, which is the study of discovering the age of a tree based on its inner rings.
Towner said that scientist Andrew E. Douglass, the founder of the lab, actually started the study of tree rings right here in the Grand Canyon State.
One could argue there is an essential beauty that lies behind tree-ring research.
By finding out more about what happens in nature, we can learn more about our world.
“Trees are natural archives of information—they stand in one place and don’t move,” Towner said. “Throughout their life, they record information.”
Studying these trees provides in-depth information about how humans treat our forests and how we can improve our environment. Towner said that the benefits of tree-ring research are quite incredible.
In addition to taking up water, trees also suck up metals and isotopes into their roots.
These trees can therefore be used in pollution studies and for research on droughts.
Visiting the tree ring lab is quite an experience. The walls are covered top to bottom in various pieces of wood that display intricate tree-rings.
Towner said the oldest tree that the lab analyzes is a core sample of a living Bristlecone Pine from the White Mountains of California.
“Our lab dated it back to over 4,800 years old,” he said. “What’s really interesting about that is that there was dead wood lying on the ground beside the tree, and it’s much older—we just don’t know how much older.”
A lot of what goes on at the Laboratory of Tree-Ring Research can be attributed back to archaeology, specifically at the Mesa Verde world heritage site in Colorado—an area that demonstrates an extreme amount of wood resources.
“Archaeology made the lab famous,” Towner said. “Because of [Andrew E. Douglass] we were able to date the Mesa Verde.”
When studying history, written records are only a few hundred years old and a lot of them are biased.
That’s the beauty of the trees, according to Towner—tree-ring records have no bias and can be dated back thousands of years.
Towner said that trees can record up to 5,000 years of rainfall. A record like this without any bias is a truly unique thing.
Trees don’t lie, and because of their record-keeping abilities, humans are able to study them and begin to make progress in aspects of nature such as ecology, fire history, insect outbreak and climate change.
The lab remains a truly interactive part of the UA.
“What really interests me are the intersections of historical human history and natural history,” said Nick Kessler, an anthropology graduate student. “That takes place a lot here in this lab. I’m an archaeologist, so I look at the trees as a tool for telling time and climate proxy.”
The tree-ring laboratory provides students, faculty and staff an excellent source of culture and history for both the university and the world.
The lab is located on campus next to the Highland Bowl and is open at UA students’ disposal, but it’s really for anyone who wants to see the beautiful works of art tree-rings are, and learn more about the effects of tree-ring dating in the process.
Correction:  The article originally stated that Charles Douglas had originally started the dendrochronology lab, Andrew E. Douglass actually started the lab.
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