CHARLESTON, S.C. (WCBD)- Despite months of protests, the massive live oak known as the “Meeting Tree” now lies in pieces.
While its estimated 300 year old story as a living Lowcountry landmark has come to an end- its prologue, written in alternating bands of light and dark wood, has just begun.
Within these faded lines, the Meeting Tree holds over a century of weather information. The historic “100 year flood” in 2015. Drought in the 1940s. Annual temperatures and rainfall trends. Even our hurricanes can be found & studied through the science of dendrochronology.
Most of us know that you can figure out a tree’s age by counting its rings and while that is true, dendrochronologists like Thomas Patterson can use them to find details about the weather over the years.
“However suitable the environment is on a given year the tree will grow more, and if the environmental conditions are not suitable for growth the tree will grow less,” he says. “So how we interpret this is when growth rings are larger, like just a larger band, we relate that to things like more rainfall or warmer temperatures.”
While thinner rings indicate more extreme events such as drought, tornadoes, forest fires, and other non-natural impacts. A tree might hardly grow at all in those years that have these stressful conditions.
So with years of information behind this oak’s belt of bark- I got to work.
First things first, getting its slab taken from the stump ready to examine.
“The chainsaw is gonna be a pretty rough cut, so you’ll start by working with coarse sandpaper, then working with progressively finer sandpaper,” Patterson said. “So what we’re looking for is a completely smooth surface.”
Once that was finished, we were able to study the tree’s rings. Counting down the years. Decades. Centuries, while taking notes and measurements on any trends that stand out.
“You had this cluster of years that were all really narrow, likely what happened is the tree underwent some sort of stress or trauma.”
Which is exactly what happened in 1989.
Patterson explains, “Think about what happens in a hurricane- high speed winds. This tree could have suffered branch damage, leaves could have been ripped off.” Leaving the tree damaged, putting it into repair mode with suppressed growth for several years afterwards- all illustrated in these thin bands.
The opposite can happen with years of increased growth if the sampled tree is left standing while a nearby tree falls during a weather event, leaving the surviving tree with more resources it previously had to fight over.
The work is meticulous and even frustrating at times as the boundaries between years are fuzzy as our winters and summers fade into one another in regards to temperature. In addition, live oaks rings are faded and wavy as the lines bend around the curved bark of the tree which grows year-round.
The findings make it worth it but one question will forever be unanswered: what is the exact age of the Meeting Tree? This piece has rings that date back to the late 1800s, years before this are unfortunately lost to heart rot which afflicts many old oaks in the Lowcountry.
Despite this set back, there still is climate data here dating back to when weather record keeping began in Charleston! Thin or thick, these rings tell the climatological history of our area which was cross referenced with temperature and precipitation records from the South Carolina State Climate Office.
While this tree’s data goes back to the late 1800s, dendrochronologists have used trees that are hundreds, even thousands of years old to chart climate change, provide possible answers to environmental mysteries, and even date indigenous dwellings. They use precision equipment to measure tree rings down to a micron- creating valuable climate data points used by climatologists to get their finger on the pulse of the environment and “ultimately have a much richer understanding of our world. And that’s the root of it. Pun intended.”
Special thanks to Melissa Griffin & others at the South Carolina Climatology Office for gathering and providing climate data used in this project.
Storm Team 2 Meteorologist David Dickson