Through the burn - Researchers plan for reseeding project on Mount Sentinel
By JOHN CRAMER of the Missoulian
Watch video from the blackened slope of Mount Sentinel
Morgan Valliant, who oversees Missoula's fight against noxious weeds, sifted through the ashes, soil and plants on Mount Sentinel's charred western slope Tuesday.
It was his first visit since last week's 390-acre grass fire on the mountainside, which is to be reseeded with native prairie grasses this fall in a pilot revegetation project by the city, the University of Montana and the Missoula County Weed District.
Stepping from his pickup, Valliant expected to find a thoroughly blackened landscape - a kind of vegetative blank slate - where invasive weeds had been largely burned away and where native grasses could be easily reseeded.
Morgan Valliant, conservation lands manager for Missoula, sifts through the dirt on Tuesday looking for cheatgrass seeds in the burned area of Mount Sentinel. The city of Missoula and the University of Montana - which both own land on the mountain - and the Missoula Countty Weed District will plant native seeds on the burned areas in the fall.
Photo by ASHLEY McKEE/Missoulian
But an up-close inspection revealed a mosaic of light, moderate and intense burns, where the seeds, roots and flowers of several aggressive noxious weed species survived the wildfire. The major culprits are leafy spurge, Dalmatian toadflax, spotted knapweed, tumble mustard and cheatgrass, whose windblown seeds were already spread like confetti across the ashes in many areas.
“I'm surprised - a little disappointed really - at how many noxious weeds are still here,” said Valliant, the city's conservation lands manager, “but this is still a great local opportunity to study how fire affects native and nonnative vegetation.”
A number of indigenous and nonnative plant species are adapted to wildfire, and studies have shown that noxious weeds often come back stronger in burned areas unless native reseeding is done.
But weed management, which includes spraying herbicides, prescribed burning, pulling weeds by hand, grazing by sheep and other methods, is still a relatively young science.
Valliant said researchers have much to learn about the relationship between fire and plant ecology, which is why city officials started thinking about the reseeding project soon after the Mount Sentinel fire started.
“Fighting weeds is a lot like fighting wildfires,” Valliant said. “You do it strategically where you'll be the most effective. We're managing for the plant community as a whole rather than just attacking spots.”
The Mount Sentinel reseeding experiment could be especially valuable because it will occur in the fall, a time when modern land managers don't use prescribed burning because of heightened fire risks.
Officials are assessing the burned areas on Mount Sentinel before deciding which ones will be reseeded in October and November. A mix of a dozen species of native grasses will be used, including rough fescue, Idaho fescue and Sandburg's bluegrass.
The focus will be on sites where noxious weeds are on the verge of overtaking native grasses.
The project's estimated cost is $60,000 depending on how many acres are reseeded and how much seed is used.
No funds have been allocated, but officials hope to use a combination of public money and private donations to complete the project. Volunteers will be needed to spread the seeds.
The new seeds could start sprouting next spring, but it will take two to four years depending on precipitation and other factors to determine whether the project is working. The revegetated areas will be monitored as part of the experiment.
The city owns about half of the acreage that burned, while UM owns the other half.
“This fire has given us a real opportunity to make some headway against these noxious weeds,” said Rob Thames, city parks superintendent. “If we don't do something, it's just going to come back worse than before.”
Valliant, who watched the wildfire from his house in the University District, said he's glad no aerial fire retardant was dropped on Mount Sentinel.
Fire retardant, which contains fertilizers, was dropped on the Mount Jumbo wildfire in 2006 and is suspected of promoting the spread of cheatgrass, the most flammable noxious weed in North America.
“As humans, we're very good at breaking these native plant communities but not at fixing them,” Valliant said. “It's easier to protect what you have than to restore what you've lost.”
For more information, call Missoula Parks and Recreation at 552-6258.
Reach reporter John Cramer at (406) 523-5259 or by e-mail john.cramer@missoulian.com.
