CORVALLIS - The 300 rifle and shotgun blasts heard last spring in the McDonald and Dunn research forests just north of Corvallis weren't part of a new hunting season.
Oregon State University researchers were just shooting trees.
They were experimenting with a more efficient way to improve habitat for cavity-nesting birds such as woodpeckers.
Whether due to thinning of dead trees, or other tree farming management practices, there aren't enough decayed trees for these birds' habitat, according to Greg Filip, a forestry specialist with the OSU Extension Service.
"We shot 100 live trees three times each with special fungi-tipped bullets," Filip said. "The bullet breaks though the tough bark of the tree and inoculates the wood with fungi. The fungi rots the interior of the tree over a period of four to five years providing soft, dead wood where birds can locate their nests.
"The fungus we use occurs naturally in the forests we are inoculating," he added. "We just collect it and culture it in the laboratory to create a larger supply."
Creating habitat by inoculating trees with fungi isn't new, says Filip. But the delivery method is.
"We used to climb up the trees, drill a hole and insert the fungi by hand," he said. "This method has been used successfully in several southern U.S. states and in Oregon near La Grande."
Fred Baker, a forestry colleague of Filip's at Utah State University, got the idea several years ago that inoculation could be done more quickly and less expensively. So Baker and Steve Daniels, an OSU professor of forestry policy, started tinkering with various bullet configurations.
Daniels says he got involved because he owns some of the reloading and machining tools need to put the bullets together. "We had a tree cut from the McDonald-Dunn Forest and took it to the Albany Rifle and Pistol Club so we could test different bullets on it," said Daniels. They settled on a 45-70 Remington shell casing with a 400-gram bullet.
"It's an older type of shell and bullet. The number 45 refers to the caliber and 70 refers to the grains of black powder used," Daniels said. "We also designed a plug that works with a 12-gauge shotgun shell. Both gave us the weight and velocity we needed to puncture the tree and spread the fungi plug."
It's been more than six months since Baker and Daniels shot the 300 trees and "it looks like the fungi survived and is beginning to start its decaying process," said Filip.