Trees may prove to be a portal to the past.
Researchers at NDSU and the University of Minnesota have received a grant from the National Science Foundation to search for evidence of historic floods along the Red River. They are looking for clues by examining trees.
Joe Zeleznik, NDSU Extension forester, and Scott St. George, assistant professor of geography at the University of Minnesota, were awarded a $349,934 grant for their research titled “Paleohydrological Assessment of Extreme Flooding Events.” NDSU’s subaward was $136,164.
The project will help determine if extreme floods on the river are becoming more common due to natural or human-related factors.
“During the past two decades, Red River floods have caused more than $3.5 billion in direct damages to communities in North Dakota and Minnesota,” Zeleznik said. “But because the known record of Red River floods only extends back to the late 19th century, other sources of information are needed to estimate the risks of future severe floods.”
Zeleznik and St. George will look for evidence of older floods in the rings of bur oak trees growing along the river. Downstream in Manitoba, similar tree-ring evidence has been used to extend the local record of Red River floods back to the middle of the 17th century.
“One hundred or so years is not long enough to take the measure of a river like the Red,” St. George said. “This award will help communities like Fargo and Grand Forks better evaluate the risk of future floods.”
On the Canadian side, the record flood occurred in 1826, decades before river observations were available along the American stretch of the river. The research Zeleznik and St. George conducts will determine whether the river produced an extreme flood in the same year upstream in the U.S.
The research team, including master’s degree and undergraduate students and volunteers, will collect samples from old oak trees in the basin, recover timbers from historic buildings and drag buried oak logs out of the river’s banks.
“Bur oaks in the Red River basin can live more than 400 years, so their rings are a wonderful source of truly long-term information,” Zeleznik said.
The NSF award’s abstract number is 1830640.