City inks contracts to thin dense forests atop Mount Sentinel

The city of Missoula and the University of Montana are partners in a project awarded this week to thin the forests atop Mount Sentinel, pictured at right, to mimic natural fire and make room for the establishment of old-growth trees. (Martin Kidston/Missoula Current)

The city of Missoula approved two contracts with two different vendors on Wednesday to thin the forests atop Mount Sentinel, a move intended to replicate natural fire and promote the development of old-growth trees.

The contracts, which include $41,800 to Miller Creek Reforestation and $17,600 to Watershed Consulting, are covered by a $67,000 grant from the Montana Department of Natural Resources and Conservation.

“The only cost to the city for this is our time and any small materials we need to go up and map these thinning units, mark these areas and do some weed spraying,” said Morgan Valliant, the city’s conservation lands manager. “That’s to fulfill the grant requirements of matching in-kind labor. We’ve got to have a 25-percent match on the $67,000 grant.”

The project, slated to take place this fall, looks to reduce fuel loads atop Mount Sentinel, though it’s not intended to reduce the threat of wildfire. Nor will the sites be managed as timber sales, Valliant said.

Rather, the thinning project looks to restore the mountain summit to a more natural condition and manage the forest for the development of old-growth trees.

“What we’re trying to do is mimic the natural cycle,” Valliant said. “Our main goal for this project is to reduce the susceptibility of the forest to pests and disease. These units are definitely overstocked because we haven’t had natural fire cycles coming through, and reducing the competition helps those trees that are there get a lot healthier.”

While the area has seen some scattered burns over the past few decades, it hasn’t endured a stand-clearing fire in more than 50 years, Valliant said.

The contract also looks to slow the forest’s encroachment onto the surrounding grasslands. Those grasslands, Valliant said, are more rare than the surrounding ponderosa pine and Douglas fir forests.

“This is an area that suffered a lot of beetle kill and we lost trees 40 inches in diameter back in the early 2000s when we had a big beetle epidemic,” Valliant said. “We’re coming in and acting like a fire and thinning out a lot of those juvenile trees to promote and protect the large, high-value trees we have on site. We also have a component where we’ll be taking a lot of juvenile trees and restoring the grassland.”

Ward 6 council member Marilyn Marler, who manages the natural areas owned by the University of Montana in Missoula County, including Mount Sentinel, said the project also looks to help the understory diversify.

“When the forest is artificially dense because of the lack of fire in the system, the plant diversity just kind of tanks in the understory,” she said.

Valliant said four contractors toured the area and three submitted bids. Miller Creek Restoration received four of the six units advertised while Watershed Consulting received two.

The project received the approval of the City Council’s Parks and Conservation Committee and now goes to the full City Council next week.