Tendoy Mountains

by Greg Iverson
Garfield Mountain
Garfield Mountain in the Lima Peaks | Rick and Susie Graetz

Northwest of Lima, Montana, the east face of the Tendoy Mountains, seemingly blends with the Lima Peaks rising on the town’s west horizon. Their abrupt ascent from the sagebrush-filled Red Rock River Valley forms what appears to be one continuing ridge. It stretches for 25 miles northward from Big Sheep Canyon, the deep, narrow and scenic meandering canyon separating the Tendoys and Lima Peaks to just above Clark Canyon Lake. 

Their west slopes descend to Medicine Lodge Creek and the Big Sheep Creek National Backcountry Byway.

Considered a subrange of the Beaverhead Mountains and part of the Bitterroot Range, these mountains were named for Chief Tendoy (1834-1907) of the Lemhi Akaitikka, or “Eaters of salmon.” At 9,674 feet, Dixon Mountain, the highest point in the Tendoys, juts above a diverse landscape interspersed with forests of Douglas fir, lodgepole pine, mountain mahogany, grasslands, and sagebrush. The area sustains healthy populations of mule deer, elk, prong-horn, black bears, mountain lions, sage grouse, and other wildlife.

Big Sheep Creek
Big Sheep Creek | Rick and Susie Graetz

The Montana Department of Fish, Wildlife & Parks is transplanting bighorn sheep to the area from Wild Horse Island on Flathead Lake as part of an effort to restore the species. (The previous population was infected by a devastating bacterium called Mycoplasma ovipheumonia, spread by domestic sheep, that causes fatal pneumonia in the wild animals.)  

Southwest Montana is known for its wide array of geology, so diverse that it is a living-breathing textbook. And the Tendoys add to that reputation. These mountains’ geologic origins date back about four-million years when a segment of the North American Plate slid over a vast source of heat known as “the Yellowstone hot spot.” In Yellowstone National Park, 100-miles southeast of Lima, this heat is responsible for the geysers, mud pots, and hot springs. But in southwestern Montana, it is partially accountable for the mountains and valleys, “basin and range” in geographic terms. 

According to geologists, the thermal energy deep underground bulged the crust above it as the tectonic plate moved over the hot spot, causing the Earth’s upper crust to stretch. This stretching was so great that crust broke into blocks detached by steep faults that allowed them to move up or down relative to adjacent blocks. The break separating them is named the “Red Rock Fault.” It can be seen above the red cliffs from nearby communities of Red Rock, Kidd, and Dell, north of Lima, along the Red Rock River. In essence, it is one linear fault.  While the east side is sharp, the range dips down in a gentler pattern on the southwest.

Tendoy Mountains at Sunrise
Tendoy Mountains at sunrise | Rick and Susie Graetz

Public lands within the Tendoys are managed for multiple uses such as cattle grazing, mining, and recreation, by the U.S. Bureau of Land Management and the U.S. Forest Service.  Some areas, including the 15,509-acre Hidden Pasture Creek Wilderness Study Area on the southern end of the range, are administered to protect their wild and scenic values. Hunting, hiking, camping, and backpacking are popular activities.

Bell and Limekiln Canyons, another wilderness study area in the range’s northern reaches, are characterized by cliffs upwards of 700′ high, caves, and a free-standing rock wall.

Access to numerous hiking trails is available from all sides—along the Medicine Lodge Road to the west, I-15 to the east and Garfield Canyon and Big Sheep Creek to the south. Whichever direction you explore this beautiful landscape, you’re sure to have a wild adventure.