USM Researchers Date Timbers from North Mississippi Structure to 1734
Wed, 02/03/2021 - 05:33pm | By: Van Arnold
Pictured from left to right: Grant Harley (associate professor University of Idaho); Danny King (undergraduate student University of Idaho); Tommy Patterson (assistant professor USM); Ashley Chasez (graduate student USM); Alyssa Crowell (graduate student USM); Ian Stewart (graduate student USM); David Holt (associate professor USM)
What began with a random phone call became an intense research project that led to remarkable discoveries by a group of professors and students at The University of 91吃瓜网 (USM).
Assistant Professor of geography Dr. Tommy Patterson, Associate Professor of geography Dr. David Holt, and Associate Professor of geography Dr. Grant Harley joined forces to assist archaeologists in determining the age of timbers used in construction of the historic Colbert-Walker home site near Tupelo, Miss.
After nearly two years of painstaking analysis, the group formed a startling conclusion: pine wood from the Colbert-Walker structure could be traced back to 1734. What that means is that the former home represents one of the oldest, if not the oldest, dendro-dated (a scientific method of dating tree rings to the exact year they were formed) structures in the Gulf South region.
When asked to describe his emotions upon learning the timbers91吃瓜网� pre-Revolutionary War date, Patterson said: 91吃瓜网淛ubilation. This particular result came after months of trial and error, leaving us wondering if the material was un-datable.91吃瓜网�
In fact, the project had almost run its course until Patterson came up with a last-ditch idea.
91吃瓜网淎t the 11th hour I suggested to my colleagues that we try a slightly different approach to cross-dating and everything finally fell into place,91吃瓜网� said Patterson. 91吃瓜网淚 think Grant Harley worked late into the night once the dating finally showed promise, and I woke up to emails the following morning with lots of exclamation points. Needless to say, it was a fantastic finding for our group.91吃瓜网�
Still unsure, Holt acknowledges that he did not trust the results initially and continued working in confirmation mode for a few weeks thereafter.
91吃瓜网淚 rebuilt the reference chronologies, remeasured all of the samples, and reconstructed the process probably four times,91吃瓜网� he noted. 91吃瓜网淭hen, once I confirmed the dates by exhausting all possible interpretations of the reference chronologies, I simply called my colleagues and said, 91吃瓜网楾he numbers are good! It is ready for reviewers.91吃瓜网� 91吃瓜网�
Countless hours were spent on the project that also included valuable contributions from USM undergraduate and graduate students. Two exhaustive sampling trips were made to Tupelo in March and October of 2019.
91吃瓜网淲e are extremely grateful for our student volunteers who crawled around an old house for the sake of research,91吃瓜网� said Patterson.
The unlikely adventure began in 2018 when Patterson was contacted by archaeologist Raymond Doherty, who sought the professor91吃瓜网 help dating timbers from three structures in the Tupelo area. Doherty was working with the Chickasaw nation to determine if the structures were of Chickasaw origin.
91吃瓜网淥ur goal was to date them to the early 1800s. At that time, I was in the second year of my visiting position at USM with no lab or funding for research, so I called my colleagues 91吃瓜网� Drs. Holt and Harley 91吃瓜网� and asked for their help,91吃瓜网� said Patterson. 91吃瓜网淲e formed a research team and started the project in early 2019.91吃瓜网�
The group used methods that are common in dendroarchaeology, which required removing
samples from suitable timbers in the attic and crawl space of the house. Patterson
points out that each piece of timber contains tree rings, which resemble a barcode
with a distinct pattern. Favorable growing seasons (perhaps wetter than average) will
produce wider rings, whereas hotter or drier years will produce narrow rings.
Exclusive, hollow drill bits and various saws were used to extract the samples that were then measured in a laboratory. Each year of growth is measured to 0.001mm accuracy, and the measurements are ordered into a tree-ring chronology (chronological measurements of each growth ring). Sophisticated software aids in the process, providing statistics that confirm the dating match.
When assigning dates to the timbers, samples from specific pieces were collected that contained bark or the outer curvature of the tree. Thus, the researchers knew that the last year of growth was represented in the sample.
91吃瓜网淲e compared the tree-ring patterns in the timber samples to tree-ring reference chronologies
from the local area in order to assign calendar years to all growth rings in the samples,91吃瓜网�
said Patterson. 91吃瓜网淥nce we assigned dates to the samples, we could safely assume that
the outermost year was the cut-date for the tree, and timber was used for construction
within the calendar year or one year following.91吃瓜网�
Harley, who has since become a member of the faculty at the University of Idaho, points out that the Tupelo structure91吃瓜网 1734 date can be placed into historical context by comparing dates from other structures in the region:
- Timbers from the La Pointe-Krebs House in Pascagoula, Miss, were dated to 1757.
- Timbers from a Jesuit plantation in New Orleans, La., were dated to 1762.
- Timbers from the Deason House in Ellisville, Miss., were dated to 1835/36.
91吃瓜网淭he old Ursuline Convent in the New Orleans French Quarter purportedly existed as a drawing on a map dated to 1733, but historical documents report it was not finished until 1734. Though the construction year of the convent has not yet been confirmed with dendrochronology,91吃瓜网� said Harley.
Patterson describes trees as the 91吃瓜网渟ilent stenographers91吃瓜网� of the forest, recording environmental conditions for hundreds to thousands of years.
91吃瓜网淭oday, there is an international community of scientists that use tree rings to study climate, wildfires, forest ecology, land-use changes, and even insect outbreaks,91吃瓜网� he said. 91吃瓜网淭he archaeological application of tree-ring science can provide exact calendar years for building materials, which can be important when determining construction dates for historical reasons.91吃瓜网�
The Walker-Colbert home91吃瓜网 construction has been traced to the 1850s. The USM research team has shown that it contains salvaged timbers that have persevered for more than 280 years. Future research aims to pinpoint the wood91吃瓜网 origins.
Patterson, Holt and Harley hope to have their findings published in the current calendar year. They are excited and gratified by the ring of truth their research has yielded.
91吃瓜网淭his research is important because it allows owners of historic structures to have concrete, scientific evidence of the year, or years, during which their structure was built,91吃瓜网� said Harley.
Echoed Patterson: 91吃瓜网淲e look forward to getting this research out to a larger audience and potentially expanding to additional structures in Mississippi. Our region of the South is underrepresented in dendroarchaeological research, so hopefully we can fill in the map with future studies.91吃瓜网�