North Lochsa Slope

The North Lochsa Slope encompasses 117,662 acres of mountainous terrain in the Nez Perce-Clearwater National Forest, rising from the Lochsa River drainage to subalpine ridges that exceed 6,600 feet. Castle Butte, Indian Grave Peak, and Grave Butte anchor the high country, while lower saddles and meadows—including No-see-um Meadows at 5,882 feet and Green Saddle at 5,416 feet—mark transition zones between forest types. Water moves through this landscape via the Lochsa River and its tributaries: Hungery Creek, Fish Creek, Deadman Creek, Canyon Creek, Bimerick Creek, Fire Creek, and Split Creek. These drainages originate in the subalpine zone and descend through increasingly moist canyons, creating the hydrological backbone of the Lochsa-Selway-Clearwater watershed.

The forest composition shifts with elevation and moisture availability. At lower elevations and on drier aspects, Ponderosa Pine / Bluebunch Wheatgrass Woodland and Grand Fir / Douglas-fir Forest dominate, with understories of broadfruit mariposa lily (Calochortus nitidus) and bank monkeyflower (Diplacus clivicola) on exposed slopes. As elevation increases and moisture increases, the Lochsa-Selway-Clearwater Canyons Mixed Conifer Forest takes hold, characterized by western redcedar (Thuja plicata), grand fir (Abies grandis), and Pacific yew (Taxus brevifolia), with western maidenhair fern (Adiantum aleuticum) and Idaho goldthread (Coptis occidentalis) carpeting the forest floor. At the highest elevations, Subalpine Fir / Engelmann Spruce Forest prevails, with whitebark pine (Pinus albicaulis) scattered across ridgelines. The Western Redcedar / Maidenhair Fern Habitat Type marks the wettest canyon bottoms, where seepage and stream proximity support dense cedar stands and lush herbaceous layers.

Large carnivores structure the predator-prey dynamics across this landscape. The federally threatened Canada lynx hunts snowshoe hares through the dense subalpine and mixed conifer forests, while the federally threatened North American wolverine ranges across high ridges and subalpine meadows. Gray wolves (Canis lupus) and American black bears (Ursus americanus) hunt elk (Wapiti) (Cervus canadensis) throughout the area. In the cold, clear streams—particularly the Lochsa River and its major tributaries—the federally threatened bull trout (Salvelinus confluentus) occupies critical habitat, preying on aquatic invertebrates and smaller fish. Westslope cutthroat trout (Oncorhynchus lewisi) and steelhead trout (Oncorhynchus mykiss) share these waters, while Chinook salmon (Oncorhynchus tshawytscha) migrate upstream to spawn. The proposed endangered Suckley's cuckoo bumble bee (Bombus suckleyi) pollinates subalpine wildflowers, and the proposed threatened monarch butterfly (Danaus plexippus) passes through during migration. Harlequin ducks (Histrionicus histrionicus) inhabit fast-moving streams, and the Coeur d'Alene salamander (Plethodon idahoensis) shelters in moist microsites near seepage areas.

A person moving through the North Lochsa Slope experiences distinct ecological transitions. Ascending from the Lochsa River canyon, the forest floor shifts from the dark, moist understory of western redcedar and maidenhair fern to the more open, drier ponderosa pine woodland as elevation and aspect change. The sound of water—first the roar of the main river, then the quieter flow of tributary creeks like Hungery Creek and Fish Creek—gradually fades as one climbs toward the high saddles. At Green Saddle and 12 Mile Saddle, the forest opens into subalpine meadows where whitebark pine stands isolated against the sky. Crossing Rocky Ridge or ascending toward Castle Butte, the canopy becomes increasingly sparse, and the understory transitions from dense herbaceous growth to low-growing alpine vegetation. The shift from canyon bottom to ridgeline is marked not only by changing forest structure but by changing air temperature, wind exposure, and the quality of light filtering through progressively thinner canopy cover.

The Nez Perce, or Nimiipuu, are the primary Indigenous inhabitants of the lands encompassing the North Lochsa Slope. For over ten thousand years, they conducted seasonal subsistence activities across this region, including fishing for salmon and steelhead in the Lochsa River and its tributaries, hunting elk and deer in the high-elevation forests, and gathering traditional plants such as camas and berries. The Lochsa River corridor and surrounding ridgelines are recognized as a Nez Perce Traditional Cultural Property, central to oral traditions, ceremonial practices including vision quests, and documented sacred sites. The river's name derives from the Nez Perce word meaning "rough water." The Salish and Kootenai tribes from present-day Montana also historically used the Lochsa River corridor and surrounding ridges to travel into the Columbia Basin to access salmon runs. During the Nez Perce War of 1877, approximately 750 Nez Perce people—warriors, women, children, and elders—used the Lolo Trail, which runs along the ridges bordering the North Lochsa Slope, to flee the U.S. Army in an attempt to reach safety in Canada. This historic route is now commemorated as the Nez Perce (Nee-Me-Poo) National Historic Trail.

The Nez Perce retained these lands under the Treaty of 1855, but the area was excluded from the reduced reservation boundaries established by the 1863 treaty, which the Nez Perce did not unanimously accept. The region initially became part of the Bitterroot Forest Reserve, established by Presidential Proclamation on February 22, 1897. On July 1, 1908, the Clearwater National Forest and Nez Perce National Forest were both established by the U.S. Forest Service from portions of the Bitterroot and Weiser National Forests. Administrative changes followed: on October 29, 1934, the Selway National Forest was discontinued, and its lands were divided between the Nez Perce and Clearwater National Forests. On July 1, 1956, the area north of the Middle Fork and the Lochsa drainage—including the North Lochsa Slope—was transferred to the Clearwater National Forest. In 2012, the Nez Perce and Clearwater National Forests were administratively combined into a single unit, the Nez Perce-Clearwater National Forests, headquartered in Kamiah, Idaho, on the Nez Perce Reservation, with the combined name chosen to show respect to the Nimiipuu.

The North Lochsa Slope remained among the last unsettled frontiers in the United States due to its rugged and steep terrain, which made large-scale industrial extraction economically unfeasible. The Northern Pacific Railroad reached the nearby town of Kooskia in 1899, but did not extend into the backcountry. Small-scale mineralogical resources exist in the broader Lochsa corridor, including vitrophyre—a volcanic glass found on the north side of the river above Fish Creek—which was historically used by Indigenous people for tool-making. The Lochsa Ranger Station, established in the early twentieth century, served as a primary Forest Service administrative site. During World War II, the nearby Kooskia Internment Camp housed Japanese-American internees who were used as labor to work on the Lewis-Clark Highway along the Lochsa River.

In 1968, the Lochsa River, forming the southern boundary of the area, was designated as one of the original rivers under the Wild and Scenic Rivers Act, protecting the corridor from dams and further industrial development. The North Lochsa Slope roadless area has been characterized by little to no large-scale historical logging or mining. In 2025, a new Land Management Plan for the Nez Perce-Clearwater National Forests was finalized, updating management standards for roadless areas.

Vital Resources Protected

Headwater Refuge for Federally Threatened Bull Trout

The North Lochsa Slope contains the headwaters of Hungery Creek, Fish Creek, and other tributaries that feed the Lochsa River—a critical spawning and rearing network for bull trout (Salvelinus confluentus), a federally threatened species with designated critical habitat in this drainage. Bull trout depend on cold, sediment-free spawning substrates and require connectivity between high-elevation summer habitat and lower-elevation winter refugia. The roadless condition preserves the intact riparian buffers and stable streambanks that maintain the cold water temperatures and low fine sediment loads these fish require to survive and reproduce.

Climate Refugia Connectivity Across Elevation Gradients

The area's subalpine forest ecosystem—dominated by Subalpine Fir and Engelmann Spruce at elevations above 5,400 feet, transitioning through mixed conifer forests to lower-elevation Ponderosa Pine woodlands—creates a continuous elevational corridor from Castle Butte (6,659 ft) to lower valley floors. This unbroken gradient allows federally threatened Canada lynx (Lynx canadensis) and federally threatened North American wolverine (Gulo gulo luscus) to shift their ranges upslope as climate conditions warm, maintaining access to cooler, higher-elevation habitat. Road construction would fragment this corridor, isolating populations in smaller patches unable to track shifting climate zones.

Whitebark Pine and High-Elevation Pollinator Network

The area supports federally threatened whitebark pine (Pinus albicaulis), a keystone species whose seeds are dispersed by Clark's nutcrackers and whose loss cascades through subalpine food webs. The roadless condition also protects habitat for the proposed endangered Suckley's cuckoo bumble bee (Bombus suckleyi) and proposed threatened monarch butterfly (Danaus plexippus), which depend on undisturbed wildflower communities—including vulnerable white bog orchid (Platanthera dilatata) and cat's ear (Calochortus elegans)—that establish in subalpine meadows like No-see-um Meadows. Road construction and associated edge disturbance would fragment these pollinator-plant networks and expose high-elevation wildflowers to invasive species colonization.

Interior Forest Habitat for Sensitive Carnivores and Mollusks

The Western Redcedar / Maidenhair Fern and mixed conifer forest types provide interior forest conditions—dense canopy, complex understory structure, and minimal human disturbance—required by Pacific marten (Martes caurina) and other forest carnivores that avoid fragmented landscapes. The roadless condition also protects riparian and seepage areas where the imperiled marbled jumping-slug (Hemphillia danielsi) and near-threatened western pearlshell mussel (Margaritifera falcata) persist in moist microhabitats. These species cannot tolerate the desiccation and sedimentation that accompany road construction and the loss of riparian shade.

Threats from Road Construction

Sedimentation and Temperature Increase in Spawning Streams

Road construction on the North Lochsa Slope's steep terrain would require cut slopes and fill material that expose bare soil to erosion. Runoff from these disturbed areas would deliver fine sediment directly into Hungery Creek, Fish Creek, and other tributaries, smothering the clean gravel spawning beds that bull trout require for egg incubation. Simultaneously, removal of streamside forest canopy during road construction would increase solar exposure to streams, raising water temperatures above the cold-water threshold (typically below 13°C) that bull trout need to survive. These two mechanisms—sedimentation and warming—act together to make spawning habitat unsuitable, with effects that persist for decades even after road construction ceases.

Fragmentation of Elevational Connectivity for Threatened Carnivores

A road network across the North Lochsa Slope would create a linear barrier and associated edge habitat that divides the continuous elevation gradient into isolated patches. Canada lynx and North American wolverine require large, unfragmented territories and avoid crossing open roads due to predation risk and human activity. Road construction would force these species to navigate around the road corridor, breaking the connectivity that allows them to track climate-driven shifts in suitable habitat upslope. Once fragmented, populations in lower-elevation patches become trapped in warming conditions with no access to cooler refugia, reducing their long-term survival probability.

Invasive Species Colonization Along Road Corridors

Road construction creates disturbed soil and a linear corridor of increased light and human traffic—ideal conditions for invasive plants to establish and spread into adjacent forest. These invasive species would colonize the subalpine meadows and forest understory where whitebark pine, Suckley's cuckoo bumble bee, monarch butterflies, and vulnerable wildflowers depend on native plant communities for food and habitat. Once established, invasive species are difficult to remove and competitively exclude native plants, degrading the floral resources that pollinators require and reducing whitebark pine regeneration success. The roadless condition prevents this invasion pathway; roads guarantee it.

Hydrological Disruption and Desiccation of Seepage-Dependent Species

Road construction requires fill material and drainage structures (ditches, culverts) that alter subsurface water flow patterns across the landscape. In the Western Redcedar / Maidenhair Fern habitat type and riparian seepage areas where marbled jumping-slugs and western pearlshell mussels persist, these hydrological changes reduce soil moisture and groundwater availability. Both species require consistently moist microhabitats and cannot tolerate the drying that accompanies road-induced drainage. Unlike mobile species that can relocate, these mollusks and slugs are sedentary; once their seepage habitat is drained, local populations are extirpated and cannot recolonize.

The North Lochsa Slope encompasses 117,662 acres of mountainous terrain in the Nez Perce-Clearwater National Forest, ranging from 5,400 feet to over 6,600 feet elevation. Five maintained trailheads and seven backcountry campgrounds provide access to a network of trails that traverse subalpine forest, mixed conifer stands, and high-country meadows. The roadless condition of this area preserves the quiet, undisturbed character essential to backcountry hiking, horseback travel, and mountain biking—activities that depend on the absence of motorized roads through the interior.

Hiking, Horseback, and Mountain Biking

The Sherman Creek Trail #203 climbs 7 miles to No-see-um Meadows (5,882 ft), a subalpine meadow offering views of the Lochsa Wild and Scenic River and the Selway-Bitterroot Wilderness. The Lochsa Downriver Trail #2 runs 16 miles along the north face of Lochsa Canyon with steep, rocky terrain and granite pillar formations; sections are open to hiking, horseback, and motorcycle use. The Weitas Creek Trail #20 follows the creek drainage for long-distance travel, with the Johnny Creek to Weitas Bridge section (5 miles) rated well-maintained and the Weitas Guard Station to 12 Mile Saddle section (21 miles, 3,929 feet elevation gain) connecting to the Lolo Motorway. Windy Ridge Trail #167 is a 14-mile singletrack climb gaining 4,761 feet through forest to subalpine ridgeline viewpoints, rated as double black diamond for mountain biking. Lochsa Peak Trail #220, accessed from the Wilderness Gateway Trailhead, climbs 3.6 miles to a saddle at 4,700 feet through forest canopy. A 20-mile loop is possible from Wilderness Gateway Trailhead using Trail #220 and Trail #211 to reach Stanley Hot Springs. Access points include the Eagle Mountain Trailhead, Sherman Creek Trailhead, Fish Creek Trailhead, Beaver Dam Saddle Trailhead, and Gass Creek Trailhead. Backcountry camping is available at Bimerick Creek Camp, Glade Creek Campground, Apgar Campground, Rocky Ridge Campground, Weitas Meadows Camp, Pete Forks Junction Camp, and Wilderness Gateway Campground. Many trails are overgrown with brush and blowdowns; maintenance is sporadic. The roadless condition keeps these trails free from motorized traffic and preserves the quiet backcountry experience.

Hunting

The North Lochsa Slope lies within Idaho Game Management Unit 12 and the Lochsa Elk Zone. Documented game species include elk, American black bear, white-tailed deer, mule deer, moose (controlled hunts in Unit 12 north of the Lochsa River), gray wolf, mountain lion, forest grouse (blue, spruce, and ruffed), turkey, and migratory waterfowl. Elk archery seasons typically run August 30 to October 9, with general any-weapon seasons extending through December. Deer archery seasons begin August 30; general any-weapon seasons for white-tailed deer typically run October 10 to November 20 or later. Black bear seasons include spring (approximately April 15–June 30) and fall (approximately August 30–October 31) hunts. In Unit 12, motorized vehicles for hunting are restricted to established roadways open to motorized traffic from August 30 to December 31; off-road vehicle use for hunting or game retrieval is prohibited. Grizzly bears may be present; specific food storage and meat handling regulations apply. The terrain is characterized by steep slopes and dense mature forest (cedar, fir, spruce) with limited visibility, making hunting challenging except in high-country areas. Success often depends on understanding elk migration patterns and accessing remote interior areas during the rut. The roadless condition ensures that hunters can reach the interior only by foot or horseback, preserving the remote character of the hunt and protecting unfragmented habitat.

Fishing

The Lochsa River borders the southern edge of the roadless area and supports native Westslope Cutthroat Trout, Bull Trout, Rainbow Trout, Mountain Whitefish, Chinook Salmon, and Steelhead. Fish Creek, a major 21.1-mile tributary within the roadless area, holds Steelhead, Westslope Cutthroat Trout, Bull Trout, Chinook Salmon, and Mountain Whitefish. Hungery Creek is a prime steelhead stream. Other tributaries including Deadman Creek, Canyon Creek, Bimerick Creek, Fire Creek, and Split Creek are part of the Lochsa drainage, managed for wild, native fish populations. On the Lochsa River, from Memorial Day Weekend through November 30, the trout limit is 2 fish with a 14-inch minimum; no bait is allowed. From December 1 through the Friday before Memorial Day, fishing is catch-and-release only for trout. Above the Wilderness Gateway Bridge, the upper Lochsa is designated catch-and-release only. All wild Steelhead must be released; barbless hooks are required for salmon and steelhead. Access to the southern boundary is available at Apgar Campground, Wilderness Gateway Bridge (Milepost 122.7), and Nine Mile (Milepost 129.5) on Highway 12. Backcountry access to interior streams is via the Eagle Mountain Trailhead (Milepost 135.3) and the Lolo Motorway (Forest Road 500) to high-elevation headwaters. The area is renowned for excellent dry fly fishing for native Westslope Cutthroat Trout in cold, clear water that serves as a climate refugium for salmonids. The roadless condition preserves the undisturbed watersheds and cold-water habitat that these native fish populations depend on.

Paddling

The Lochsa River is the primary paddling destination, classified as Class III to IV+ whitewater. Notable rapids include Lochsa Falls (Class IV), Grim Reaper (Class IV), House Wave/House Rock (Class IV), Ten Pin Alley (Class III+ to IV+), and Split Creek Rapid (Class III+ to IV). The lower Lochsa section from Split Creek to Lowell is Class II to III, with Hellgate as the most challenging rapid. The paddling season runs April/May through June, depending on snowmelt. Recommended flows range from 1,500 to 25,000 cfs, with high water (May/early June) at 12,000–25,000 cfs and medium/low water (mid-to-late June) at 3,000–12,000 cfs. Fish Creek serves as a primary put-in with a large parking area and ramp. Split Creek Pack Bridge is a common take-out for the Class IV section and put-in for the lower Class II section. Knife Edge (Mile 107) is an alternative put-in for shorter Class II floats. Bimerick Creek is used for vehicle shuttles. Lowell River Access is the final take-out at the Lochsa-Selway confluence. Lochsa Madness, an informal annual gathering, occurs over Memorial Day Weekend at Lochsa Falls (Highway Mile 114.5). The roadless condition preserves the wild character of the river corridor and the undisturbed riparian habitat that supports the fishery and wildlife populations along the paddling route.

Photography and Wildlife Viewing

Castle Butte Lookout (6,659 ft) is an active fire lookout offering 360-degree views of the Selway-Bitterroot Wilderness, Seven Devils Mountains, the Great Burn, and the North Fork Clearwater River drainages, accessible via the Lolo Motorway (Forest Road 500). The Lochsa Downriver Trail #2 provides views of the Lochsa River and surrounding mountains. Lochsa Peak offers panoramic views from its summit approach. Indian Grave Peak (6,446 ft) along the Lolo Motorway provides expansive views of the Lochsa drainage. Snowshoe Falls (near Milepost 117.5 on Highway 12) and Tumble Creek Falls (visible from Highway 12) are accessible by short hikes. Lochsa Falls (Milepost 114.5) is a scenic water feature popular with photographers. High-mountain lakes are accessible from the Lolo Motorway near Castle Butte. Meadows and hillsides along the Lolo Motorway display colorful wildflowers during summer months. The Colgate Licks National Recreation Trail is a 1-mile interpretive loop featuring open meadows with spring and summer wildflowers and a natural mineral lick. The Devoto Cedar Grove near the eastern edge contains ancient Western Redcedars, some over 2,000 years old. No-see-um Meadows (5,882 ft) is a high-elevation subalpine meadow. Elk are frequently seen grazing in open meadows and along the Lochsa Downriver Trail in springtime. Black bear, moose, and mule deer inhabit the area. The Lochsa River corridor and tributaries provide habitat for Harlequin Ducks and Coeur d'Alene Salamanders. The Lochsa Historical Ranger Station area is noted for birdwatching. Castle Butte Lookout, at high elevation in an extremely remote location, offers stargazing with minimal light pollution. The roadless condition preserves the quiet, undisturbed setting that allows wildlife to move freely and photographers to experience the landscape without the sight and sound of motorized traffic.