Forest Park Trees Dying?

A Linfield College environmental studies professor says her research in Forest Park —one of the largest urban parks in America— shows that trees are dying younger and more quickly.

Linfield prof Nancy Broshot has data showing, in some areas, a 75 percent death rate over a 10-year period ending in 2003. Broshot selected 24 sites in the 5,100-acre park, each spanning 750 square meters, where she recorded the number and diameter of trees and shrubs. The study finds that most trees are dying younger, and fewer saplings are surviving to replace them.

“That shocked me," Broshot says. "It was bizarre.”

Broshot's recent release of her findings comes at the same time as an advisory committee is working on a proposal to balance mountain bike use in the park. This year already, an illegal mountain bike trail damaged an area of Forest Park with 400-year-old Douglas firs. “We're basically loving Forest Park to death right now," Broshot says. "I don't know if even limiting use would help because people are off the trails all over the place.”

Portland Parks and Recreation natural area supervisor Dan Moeller says the study is helpful, but that it raises more questions than answers.

“Nancy has recorded some good data. It's a good starting point. I think it's extremely speculative at this point,” says Moeller.

He says there are plenty of remote areas with vigorous wildlife, and that the study does not reflect a large enough area to capture the vast and diverse forest. Moeller finds that Broshot's research sites tend to be in heavily used trailheads that she picked to minimize her footprint and for easy access.

“That's the one thing about researching Forest Park – it's enormous," Moeller says. "In any one study it would be really difficult to cover it all.”