Indiana State University Newsroom

Living the adventure: Students track moths, core trees

June 27, 2010

Jim Speer knelt on the ground examining soil as he gave hope to the Indiana State University students around him.

"I would expect larvae on the trees because the moths should have been out here laying eggs last year," said the Indiana State associate professor of earth and environmental systems.

Students began looking at the Jeffrey pine trees after Speer finished describing the larvae as inch-long black, furry caterpillars.

"I found one," Peter Rosene called after mere seconds of searching.

Speer hurried to the junior pre-law major's side.

"Oh, sweet. It's our first Pandora moth and he's feeding too," Speer said as the other five students gathered around.

In that instant, the three-week, 6,800-mile research trip brought together the two components: Pandora moths and ponderosa or Jeffrey pine trees.

"I was beginning to get a little scared that we weren't going to find anything on this trip," Rosene, a West Terre Haute resident, said.

"We'd been searching for them for nine days now and not had any luck," Speer said. "To actually be able to gather them sets our research forward quite a bit. We can start doing genetic analysis on those. That analysis has never been done on Pandora moths so we don't even know what markers to identify."

During this National Science Foundation-funded research trip, Speer and his students examined the Pandora moth range from New Mexico and Arizona throughout California, searching for moths and taking tree core samples. The University of Hawaii, a partner in the project, will conduct genetic analysis of the trees and moths.

"We're trying to sample the entire range of the Pandora moth," Speer said. "Just by looking at Pandora moths from different locations they actually have different morphologies, they look a little different. So one thing we're testing is to see if we really are dealing with one species."

Speer and Indiana State students took core samples to study the ponderosa and Jeffrey pine trees' interactions with the moths. Trees not only record their age in tree rings, but also fires and insect outbreaks.

Pandora moths depend on ponderosa and Jeffrey pines as well as grus - granite sand soil - for their life cycles. Larvae feed on the pines, stripping them of needles before burrowing in the soil to emerge one year later as the mature Pandora moth. While the moths only kill 2 percent of the trees, they do leave a mark, one that dendrochronolgists - those who study tree rings - can find in examining the trees' histories.

"The tree will really decrease in growth, half the growth of normal," Speer said. "We'll be able to see that for a long period of time (in the rings)."

At each site throughout the Southwest and California, students took pencil-sized samples with increment borers from old trees. Back in the laboratory at Indiana State, students will study the cores, searching for times when Pandora caterpillars affected the trees' growth, tracking the years when moth outbreaks occurred.

To get those samples meant the six students and two Indiana high school science teachers spent days hiking and nights camping in national forests between 6,000 and 7,000 feet in altitude.

"It's not setting up camp in one area and spending a week there," said Dorothy Rosene, a senior environmental science major. "We're only in one place for a day or two."

Those days and nights away from their daily lives impacted the students.

"They get to see what field work is about. They get to experience these amazing places," Speer said. "I think a lot of times they come out and don't really know how much they can do."

Tony Bailey, a senior anthropology major from Terre Haute, learned not only how to core trees but also how to count tree rings, and how to look for fire scarring in trees. Because of how he learned, Bailey said he won't forget.

"If someone had told me how to use this borer to take a core out of the tree, it wouldn't be near the same as going out and actually doing it," he said as he twisted the borer into the tree. "Basically, me doing this right now, I can remember for the rest of my life. If we only talk about how to do it, then I'm going to lose it."

Kristen De Graauw, environmental and earth systems graduate student from Nashville, Tenn., agreed with Bailey.

"You can't learn anything without learning it hands on, especially in this field," she said. "De Graauw studied dendrochronology for her undergraduate degree but she didn't learn about insect outbreaks or fire history. "For me to learn how to do this, I can't read a book. It doesn't teach me anything and I want to learn how to do this. I want to be very well rounded in dendrochronology so I really thought this was the best experience."

For Dorothy Rosene, the experience equals one thing.

"You're doing science," she said.

And it is science that moved the participants through the desert to the mountains exploring the Western United States where many had not visited.

Peter Rosene had looked forward to seeing the Sonora and Mojave Deserts - his first time to see such a arid environment.

"It's beautiful in its own way," he said. "You don't have to have trees and grass to make it an ideal environment. You can have sand and cacti and do just the same."

One of geology graduate student David Bohnert's favorite days involved working in the shadow of the Sierra Nevada Mountains.

"We cored on a site with snow capped mountains in the background," said the Terre Haute resident. "We had to cross a beautiful meandering stream to go up the side of a cliff face only to look at all these mountains and ponderosa pine trees that are majestic in their own right."

During the trip, scientific purpose merged with the beauties of the desert, mountains, and, even, the Pacific Ocean.

"I get excited every day I wake up," Bohnert said. "We always have a journey to go on. It's the way to live, I think, just adventurous."

Watch Trees and Moths Video >>

Dorothy Rosene picks a Pandora moth larvae off the tree while her brother, Peter Rosene, watches near Mammoth Lake, Calif. (ISU Photo/Jennifer Sicking)

Photo: Robin Van De Veer, geology graduate student, and David Bohnert, geology graduate student, examine a soil sample near Payson, Ariz. ISU Photo/Jennifer Sicking

Photo: Tony Bailey, a senior anthropology major, takes notes while Kristen De Graauw cores into a ponderosa pine tree. ISU Photo/Jennifer Sicking

Photo: Associate Professor Jim Speer and Peter Rosene, senior political science major, look at tree core. ISU Photo/Jennifer Sicking

Contact: Jim Speer, associate professor of geography and geology, 812 237-3011, 
Writer: Jennifer Sicking, assistant director of media relations, at 812-237-7972 or