The Centennial Mountains

The Centennial Mountains are one of the few ranges of the Rockies that run from east to west (instead of north to south). The Centennials are the Idaho/Montana state line and also the Continental Divide. A roadless area extends along the crest of the range on the Idaho side, and it extends down to the floor of the Centennial Valley on the Montana side -- the side with the steep, bold front. Total size of the area is about 120,000 acres, some 3/4 of it in Montana. This includes the Red Rock Lakes National Wildlife Refuge Wilderness on the valley floor. The Refuge wilderness is bisected by a road at the base of the Centennial mountain range.

The Montana side of the Centennials. Photo taken just west of Red Rock Pass
 Centennial Mountains, Montana
  © Ralph Maughan

Unlike nearby Island Park, Idaho, the Centennials are largely covered with Douglas fir rather than lodgepole pine. However, the drought that began in 2000 and lasted until 2005 weakened the fir, many of them giants, and most are dying of the Douglas fir bark beetle.

Ching Creek douglas fir
© Ralph Maughan. Giant Douglas fir along Ching Creek. Centennial Mountains, Idaho

Continental Divide. Centennial Mountains, Idaho
On the Continental Divide, an approaching front over Mt. Jefferson
Centennial Mountains, Idaho/Montana

Copyright © Ralph Maughan.


The Idaho side of the mountains has a gentler slope than the Montana. Consequently it has been hit harder by logging. To compensate for the effects of the logging, the Targhee National Forest has tried to protect wildlife habitat above the logging line by issuing vehicle closures to the area. They have had some summertime success (although violations are common). However, the Targhee allows folks on the new high-powered snow machines to prowl the crest far into the springtime. Some think this is detrimental to the wildlife that just survived the winter.  

Icehouse Creek at the base of Idaho side of the Centennials.Icehouse Creek, Centennial Mountains, Idaho

Copyright © Ralph Maughan

Despite the heavy logging of the lower elevations in Idaho, the Centennial Mountains still provide the most diverse wildlife habitat on the Targhee National Forest. They are noted for their fine elk hunting. Present also are deer, moose, pronghorn antelope, black bear, cougar, and (rarely) a grizzly bear or two.

 The Montana side of the range is managed by four agencies. A small portion in Hellroaring Creek is on the Beaverhead National Forest. Adjacent is a larger parcel administered by the U.S. Sheep Experiment Station, headquartered in Dubois, Idaho. A good deal of the Montana side is administered by the U.S. Bureau of Land Management who have designated their portion of the area as a "primitive area." The rest is part of the Red Rock Lakes National Wildlife Refuge and Refuge Wilderness. Most of it is on the marshy floor of the Centennial Valley, home to trumpeter swans and much other waterfowl.  

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/ Jan.20, 2006