PLU Researchers Are Exploring a Hidden World in Tacoma’s Trees

A small stand of trees can be easy to pass without a second glance. For a PLU biology team, the aspen groves scattered around the Tacoma area are places to ask a much bigger question: what lives in them, and what might they reveal about the surrounding land?

Biology students Ayre Takamoto and Corban Piper spent the summer working with assistant professor Olivia Cope on some of the first focused field research into these South Sound aspen communities. Their project examines both the trees and the insects they support.

The team is studying three sites. At each one, they tagged 30 trees and recorded details including tree height, the number of young trees nearby and signs of insect activity. That gives them a way to compare groves that may look similar from a distance.

Some clues are visible on the leaves: holes where insects have fed, for example. To see more, the researchers hold a white tarp beneath branches, strike the branches with a yardstick and collect the insects that fall. Back on campus, they examine labeled specimens under microscopes.

They want to learn whether the insect communities in separate groves are connected and how Tacoma’s low-elevation aspens compare with aspens in other regions. Development has left these local stands fragmented, Cope told PLU, making them especially interesting to study.

Another question could have practical value: whether aspens can help indicate the presence or condition of wetlands. The researchers have not established that connection yet. Piper hopes enough evidence could eventually make the trees useful in efforts to identify and protect wetlands.

Aspens are part of Tacoma’s documented landscape. An earlier City of Tacoma habitat assessment, for instance, listed quaking aspen among the tree species found at First Creek.

For Takamoto and Piper, the project has also meant learning how field observations become usable data. Their work moves between the groves, the microscope and analysis on campus, giving them research experience beyond a classroom exercise.

The answers will take more work. For now, the project draws attention to a part of the local environment many of us overlook: small, separated groves with their own insect life and potentially more to tell us about the wetlands nearby.

Read the original article and view more photographs here.