Chapter 2: Biogeographic, Cultural, and Historical Setting of the Northern Rocky Mountains S. Karen Dante-Wood The Northern Rockies Adaptation Partnership (NRAP) Mountains lie in the northern portion of the panhandle from includes diverse landscapes, ranging from high mountains Lake Pend Oreille in the north to Lake Coeur d’Alene in the to grasslands, from alpine glaciers to broad rivers (fig. 1.1). south, and the Clearwater and Salmon River Mountains are This region, once inhabited solely by Native Americans, located south of the Coeur d’Alene Mountains. has been altered by two centuries of settlement by Euro- Continental glaciers shaped the topography of this Americans through extractive practices such as timber panhandle region by excavating lake basins and deposit- harvest, grazing, and mining, water diversions, and other ing glacial till and outwash. The bedrock found here is activities. Although relatively little urbanization is pres- composed of sedimentary rocks of the Belt Supergroup, ent in this region, paved and unpaved roads and electrical deposited 1,470 to 1,400 million years B.P. Deposition took transmission wires permeate much of the landscape. place in a large basin where space was not a limiting factor Federal agencies own and manage a significant portion of and the sediment was able to build up vertically (Idaho State the Northern Rockies, including 15 national forests and 3 University 2014a). This process created large deposits of national parks. silver, lead, and zinc in the Coeur d’Alene area. Resource conditions, resource management issues, ef- The Western Rockies subregion contains many large fects of climatic variability and change, and climate change rivers. Commonly referred to as the “River of No Return,” adaptation options differ greatly from Idaho to North Dakota the Salmon River winds 425 miles through central Idaho and from the Canadian border to Wyoming. To capture these and divides the northern and southern part of the State. differences, the NRAP climate change vulnerability assess- The canyon gorge is deeper than the Grand Canyon of ment and adaptation strategy were conducted for each of Arizona. It is one of the longest rivers in the State and five subregions: Western Rockies, Central Rockies, Eastern renowned for its spawning beds for Pacific salmon species. Rockies, Greater Yellowstone Area, and Grassland. These The Clearwater River, also in Idaho, is fed by the Bitterroot subregions are briefly described next. Mountains and was preferred by explorers, trappers, miners, and loggers because it was easier to navigate than the tur- bulent Salmon River (Idaho State University 2014b). Other Western Rockies Subregion rivers include the Kootenai and Pend Oreille, which flow into the Columbia River. The Clark Fork of the Columbia The Western Rockies subregion occupies about 17 mil- River feeds into Lake Pend Oreille; and the Saint Maries, lion acres across portions of Idaho and Montana, including Saint Joe, and Coeur d’Alene Rivers flow into Lake Coeur the Idaho Panhandle, Kootenai, and Nez Perce-Clearwater d’Alene. Priest Lake and Hayden Lake near Pend Oreille are National Forests and several Native American reservations heavily used for recreation because of their scenic setting (e.g., Nez Perce Indian Reservation, Coeur d’Alene Indian among forested mountains (Idaho State University 2014b). Reservation). Most of this subregion is extremely mountain- Idaho is only 300 miles from the Pacific Ocean, so its ous and heavily forested; the mountains are broken by river climate is affected by a maritime atmospheric pattern that and stream valleys and two large grassland ecosystems, brings more precipitation to northern Idaho than to southern Big Camas Prairie and Palouse country. The subregion also Idaho. Summers are typically hot and dry, and winters are includes 1.7 million acres of wilderness lands. relatively cold due to the high amount of moisture carried The Rocky Mountains encompass a large area of Idaho through the Columbia River Gorge. and extend from the Idaho panhandle along the Wyoming The most actively managed forests in the Western border. To the west of the Rockies lie the prairie lands of Rockies are found in northern Idaho, which is character- Washington and Oregon, and the east is home to mountain- ized as a steppe-coniferous forest alpine meadow province ous western Montana. A distinguishing feature of this region (Schnepf and Davis 2013). A 2012 Forest Service, U.S. is the rugged mountains that extend lengthwise along the Department of Agriculture (USFS) report used Forest panhandle. The Bitterroot Mountains occupy the Idaho pan- Inventory and Analysis data to describe various forest handle along the Montana/Idaho border, the Coeur d’Alene cover types in the subregion. The six most common forest 16 USDA Forest Service RMRS-GTR-374. 2018 Chapter 2: Biogeographic, Cultural, and Historical setting of the northern rocky mountains groups are Douglas-fir (Pseudotsuga menziesii), subalpine (Odocoileus virginianus), mule deer (O. hemionus hemio- fir (Abies lasiocarpa)/Engelmann spruce (Picea engelman- nus), elk (Cervus elaphus), moose (Alces alces), coyote nii)/mountain hemlock (Tsuga mertensiana), lodgepole (Canis latrans), gray wolf (Canis lupus), bobcat (Lynx pine (Pinus contorta var. latifolia), ponderosa pine (Pinus rufus), cougar (Puma concolor), and wolverine (Gulo gulo). ponderosa), western hemlock (Tsuga heterophylla)/Sitka Smaller vertebrates include Coeur d’Alene salamander spruce (Picea sitchensis), and quaking aspen (Populus (Plethodon idahoensis) and pygmy shrew (Sorex hoyi). tremuloides)/paper birch (Betula papyrifera) (Sullivan et al. Among the broad range of avian taxa are bald eagle 1986). Commercially harvested coniferous species in this (Haliaeetus leucocephalus), golden eagle (Aquila chry- area include Douglas-fir, Engelmann spruce, grand firAbies ( saetos), osprey (Pandion haliaetus), many species of grandis), lodgepole pine, ponderosa pine, subalpine fir, owls, wild turkey (Meleagris gallopavo), California quail western hemlock, western larch (Larix occidentalis), west- (Callipepla californica), greater sage-grouse (Centrocercus ern redcedar (Thuja plicata), and western white pine (Pinus urophasianus), blue jay (Cyanocitta cristata), and calliope monticola). Other species not used for wood products in- hummingbird (Stellula calliope). clude whitebark pine (Pinus albicaulis), limber pine (Pinus Both native and nonnative fish are found in many flexilis), alpine larch (Larix lyallii), mountain hemlock, and Western Rockies rivers and lakes, making it a popular western juniper (Juniperus occidentalis). Quaking aspen, area for angling and spawning. Fish species include native black cottonwood (Populus nigra), and paper birch are also cutthroat trout (Oncorhynchus clarkii), rainbow trout (O. commonly found. mykiss), the Federally threatened bull trout (Salvelinus Western white pine is an important tree species to this confluentus), and nonnative brook trout (Salvelinus fontina- region. It grows on a variety of soil types and slopes and can lis). The Kootenai River is home to the endangered white regenerate across a broad range of environments. Western sturgeon (Acipenser transmontanus) and threatened burbot white pine forests usually originate from wildfires and when (Lota lota). the species matures, it can survive fire better than nearly all Wildfire is a dominant influence on the structure, func- of its shade-tolerant competitors. Although the species can tion, and productivity of forest ecosystems in the Western survive to an age of 300 to 400 years, it is declining due to Rockies. Fire frequency varies greatly depending on biogeo- white pine blister rust (causal agent: Cronartium ribicola). graphic conditions, with stand replacement fires occurring Common shrub species in the subregion include western at 50- to 500-year intervals, and surface fires occurring in serviceberry (Amelanchier alnifolia), red osier dogwood dry forests at 2- to 50-year intervals. Frequent fires keep (Cornus sericea), oceanspray (Holodiscus discolor), Lewis many forests in the early stages of succession, as indicated mockorange (Philadelphus lewisii), huckleberry (Vaccinium by high numbers of western larch and pine (Schnepf and membranaceum), and smooth sumac (Rhus glabra). Davis 2013). In contrast, fire exclusion during the past 80 Evergreen shrubs include Oregon-grape (Berberis aqui- years or so has reduced fire frequency in lower-elevation dry folium), snowbrush ceanothus (Ceanothus velutinus), and forests, resulting in dense stands and elevated accumulation mountain lover (Paxistima myrsinites); evergreen ground- of surface fuels. covers include kinnikinnick (Arctostaphylos uva-ursi), and Mountain pine beetle (Dendroctonus ponderosae) kills twinflower (Linnaea borealis) (Sullivan et al. 1986). large numbers of lodgepole pine, often in outbreaks of Ecologically diverse habitats in the Western Rockies thousands of acres, and it increasingly kills whitebark pine subregion also support a large number of rare plant species. and limber pine at high elevations as the climate continues The warm, dry grassland areas in the western part of the to warm. Western spruce budworm (Choristoneura oc- subregion harbor populations of Spalding’s catchfly (Silene cidentalis) causes sporadic outbreaks in Douglas-fir and spaldingii), a Federally threatened species, and Palouse true firs (Abies spp.), and Douglas-fir tussock moth (Orgyia goldenweed (Pyrrocoma liatriformis). In contrast, the much pseudotsugata)