MISSOULA — The Lolo National Forest still doesn’t know the source of the mud that’s fouling the Blackfoot and Clark Fork rivers.
On Friday afternoon, the Lolo National Forest confirmed that heavy rains caused the Monture Trail to wash out above Yellowjacket Creek about four miles in from the trailhead.
But the washout has been eliminated as the main source of mud. The trail washed out more than three days ago, and the rivers are still cloudy.
“We are unable to pinpoint any large, single source of sediment load so far,” said Quinn Carver, Seeley Lake district ranger.
“Although the creeks in the Monture drainage are intermittently running cloudy and likely contributing to the recent discoloration of the Blackfoot, we don’t believe it is the sole source of the discoloration.”
During the 2017 Rice Ridge Fire, the Yellowjacket drainage in particular experienced moderate- to high-severity burns, creating conditions that make landslides more likely because little vegetation remains to secure the soil in place.
Carver is cautioning people intending to use the Monture Trail to be careful.
The narrow section of trail over the Yellowjacket drainage is on a steep, exposed mountainside, and although the area is still passable by foot, boulders and woody debris have made the slope hazardous. Backpackers should exercise caution, and day-riders should use the flat section before Bill Creek as a turnaround point prior to reaching the blind corner leading to the Yellowjacket drainage.
Alternate routes for riding into the Bob Marshall Wilderness include Pyramid Pass Trail #416, Lodgepole Creek Trail #13, Hobnail Tom Trail #32, and Dry Fork Trail #31.
Crews are scheduled to head into the site on Monday to work on the Monture Trail. Making the trail stock-worthy again will likely take several days.