In a season of extreme weather, a rare mountain tornado and microburst toppled 1,000 acres of timber on the north side of the Crazy Mountains on July 2, leaving the Gallatin National Forest and an adjacent landowner with a mess.
“We’re looking at our options, including removal of some sort,” said Marna Daley, public affairs officer for the Gallatin. “It would be 2011 before we’d be able to implement any management action.”
The combined wind events piled douglas fir, lodgepole pine and spruce trees up to 20 feet high in some areas at the headwaters of the Shields River. Aerial mapping shows patches of blowdown from near the mouth of Lodgepole Creek to south of Target Rock while moving east to Crandall Creek and Loco Peak.
“We’re really focusing on understanding the extent of the blowdown and what the public safety aspects of it are — what trail and road facilities have been impacted,” Daley said.
The blowdown shouldn’t present a wildland fire risk this year, Daley said, since the trees are still green.
“The danger is more likely to come next year after the material dries out and becomes more of a fire hazard,” she said.
The tornado that struck the Crazy Mountains was rated an EF2, capable of producing winds up to 120 mph, said Matt Solum of the National Weather Service office in Billings. The tornado created a path 150 yards wide and two miles long through the timber. To the right of the tornado the microburst struck, widening the destructive path that was found up to a mile south of the tornado damage.
“Trees as large as three to four feet in diameter were uprooted or snapped off,” Solum said.
The two wind events could be distinguished from the air. Trees toppled by the tornado were laid down in a circular pattern while trees hit by the microburst were all facing the same direction.
The storm systems hit two days after golf ball-sized hail caused millions of dollars of damage in nearby Bozeman. The storm front that hit the Crazies occurred between 3:45 and 3:52 p.m., said Dan Borsum of the National Weather Service.
Tornadoes are unusual in the mountains, but not unheard of. In 1987, a tornado with 160 mph winds struck the Tetons in Wyoming and leveled an estimated $2.5 million worth of timber, Borsum said.
“We see rotation in storms all the time,” he said. “In the mountains, the rotation doesn’t have as far to reach the ground.”
Private land damaged
The damage wasn’t limited to federal land. Daley estimated that of the 1,000 acres of trees downed, about 600 were on the forest in an inventoried roadless area and 400 were on a 2,437-acre ranch owned by Muffie B. Murray of Greens Farms, Conn.
In 2005, Murray exchanged private lands for forest land to consolidate her holdings and paid $72,000 for the construction of a new Bennett Creek rental cabin because the old one was on the land the forest traded.
Contact Brett French at firstname.lastname@example.org or 657-1387.