Larson presents invasive earthworm research at the world's premier tree-ring laboratory

February 28, 2013
Dr. Evan Larson


PLATTEVILLE, Wis. – Dr. Evan Larson, assistant professor of geography at the University of Wisconsin-Platteville and faculty member in the UW-Platteville Tree-Ring, Earth and Environmental Sciences Laboratory, recently presented an invited lecture at the University of Arizona Laboratory of Tree-Ring Research, the largest such facility in the world.

Larson’s lecture was the first tree-ring talk in the first series of lectures to be given in the new, state-of-the-art Bryant Bannister Tree-Ring Building. While out west, Larson also presented an invited lecture at Willamette University in Salem, Ore., where he is developing a project involving tree-ring chronologies from ancient Oregon white oak trees in the Willamette Valley.

Larson said it was an honor to speak at both locations; he completed his undergraduate work at Willamette in 2002, and the LTRR in Tucson, Ariz., is recognized worldwide as the preeminent center for the advancement of tree-ring techniques and the broad application of dendrochronology (tree-ring dating) in the social and environmental sciences.

Both opportunities allowed Larson to share research that is happening at UW-Platteville. He said it couldn’t have come at a better time; the TREES Laboratory is engaged in new research on the impact of invasive earthworm species in Great Lakes hardwood forests that uncovers implications for tree-ring research everywhere.

“Earthworms fundamentally alter the environment where trees are growing and influence how trees respond to climate,” Larson said. “This is a problem because it presents a major complication for using tree-rings to reconstruct past environments. If trees are responding differently to climate now than they were in the past, the fundamental principle of uniformitarianism does not hold true and it inserts an immense amount of uncertainty into our work. This is particularly true for reconstructing patterns of drought in the Great Lakes region where forests are most impacted by invasive earthworms.”

To date, Larson and his students have presented their research findings on earthworm impacts from the Menominee and Chequamegon forests at conferences in Anchorage, Alaska; Chicago; New York City; Seattle; Washington, D.C.; and Mar del Plata, Argentina.

Being able to share research at the LTRR, in particular, helps to further publicize the work, identify additional grant funding, and recruit faculty and staff for future opportunities in the UW-Platteville TREES Laboratory, as well as open up more collaborative opportunities, Larson said.

Larson has four more invited lectures coming up this semester. “The timing was such that all of these opportunities came up at once and each one is key to moving the mission of the TREES Laboratory and UW-Platteville forward,” he said.

Contact: Dr. Evan Larson, assistant professor, UW-Platteville Geography Program, (608) 342-6139,

Written by: Barbara Weinbrenner, communications specialist, UW-Platteville College of Liberal Arts and Education, (608) 342-6191,



Subscribe to RSS FeedSubscribe to news at University of Wisconsin-Platteville using our RSS feed.

Footer Anchor