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Land Resources and Uses
Nevadans past and present have overcome the hardships that arid valley and steep mountain environments can impose on human enterprise. To the casual observer, a vast majority of the state may appear vacant, wide-open, and wild. A closer look reveals that the land and all it bears has long been put to productive and recreational uses.
Land here is grazed by livestock; irrigated and farmed; logged for wood products and fuel; mined for gold, silver, copper, and other metals; drilled for oil and geothermal energy; developed for rural and urban communities, industry, and transportation; and, enjoyed by a wide variety of outdoor recreationists. However, the dry climate and rugged landscape leave little margin for excessive use or neglectful management of the soil, water, vegetation, and wildlife. Decisions about resource utilization, especially water, greatly impact ecosystem health and the socioeconomic well being of communities. Sustaining resources harvested and extracted for food, fiber, energy, and minerals depends upon careful and vigilant stewardship of the environment by all individuals and institutions.
People often think of the landscapes around them in terms of the dominant land use or vegetation cover. Common terms include rangeland, forestland, farm and ranch land, mineral resource (mining) land, military land, urban and suburban developed land, and wilderness. Part 4 uses these terms to organize information about the land and resource use in Nevada. Land cover and land use types were mapped by Utah State University in collaboration with the BLM and USFS using circa 1990 satellite images (Gap Analysis Program, circa. 1995). Not surprisingly, the analysis shows that about 81 percent, or 57.5 million acres, of Nevada's landscapes can be described as rangeland (Table 4-1). Forestland, including pygmy conifer (pinyon and juniper) woodlands, covers about 8.5 million acres, or 12 percent of the state. Wetlands and riparian zones cover about 0.7 percent of the state's land area. The estimate of 0.5 million acres for this land cover type probably underreports the actual amount. Similarly, agricultural land estimated at 1.4 million acres, may be understated, since irrigated fields are rotated and only a portion of farmland receives water each year.
Rangeland
Rangeland covers an immense portion of the state and provides a variety of ecological and economic benefits. Benefits of healthy rangeland include watersheds for rural and urban uses, livestock products, wildlife habitat, and land for urban development. These lands also provide aesthetic value, open space, and outdoor recreation. Rangeland is often used to refer to a group of vegetation zones composed primarily of shrubs, grasses, and forbs that are suitable for grazing and browsing animals, most notably domestic livestock, large herbivores (e.g., mule deer, elk), and wild horses.
About 57 million acres (81 percent of the state) may be classified as rangeland. The vegetation zones include: sagebrush, mountain sagebrush, and sagebrush/perennial grass (sagebrush zone); salt desert scrub, greasewood, blackbrush, and Mojave mixed scrub (lowland shrub zone); dry meadows and perennial and annual grasslands (herbaceous and grasses zone); creosote/bursage (creosote zone); and, bitterbrush, mountain shrub, and Sierra mountain shrub (mountain shrubs) (Figure 4-1).
Streams, springs, and patches of wetlands and riparian zones, woodlands, and forested areas are interspersed throughout rangelands, adding to the diversity of wildlife and variety of human uses. Rangeland uses include livestock grazing, ranching and farming, outdoor recreation, wildlife and fish habitat, wild horse and burro habitat, mining, and urban and rural community development.
Herbaceous and grass type covers about 1.9 million acres dispersed throughout the state. The dry meadow type is most prevalent in the foothills and mountains of northern Great Basin, Columbia Plateau, and the Sierra Nevada ecoregions. The grassland type is a northern Nev ada feature, consisting of cheatgrass monocultures or grasslands, introduced perennial grasslands, or patches of native grasslands. Well-represented native grass species include wheatgrasses, bluegrasses, needlegrasses, basin wildrye, blue gramma, squirreltail, and Indian ricegrass.
The lowland shrub zone includes salt desert scrub, greasewood, blackbrush, and Mojave mixed scrub. Lowland shrubs cover 20.4 million acres on valleys and slopes below 5,000 feet. The largest expanses occur in the southern, central and northwestern part of the state, including the Mojave and Amargosa deserts northward to the Black Rock and Smoke Creek desert basins. This zone receives the least precipitation and experiences the warmest temperatures. Moist, saline soil conditions exist in some valley bottoms, generally identifiable by the presence of greasewood and salt grass, often up to the edge of a playa.
In the salt desert scrub zone, dominant shrubs include shadscale, greasewood, winterfat, budsage, horsebrush, fourwing saltbush, and mormon tea. Saltgrass, Indian rice grass and cheatgrass area associated species. The salt desert scrub zone provides winter forage and cover for many forms of wildlife and livestock. Mojave desert mixed scrubland occupies lower slopes, washes or upland areas. The zone is characterized by creosote with bursage, desert thorn, hopsage, blackbrush, yucca, and cacti. The creosote-bursage zone is widely distributed in the Mojave Desert below 4,000 feet on valley floors and mildly sloping lowlands. Blackbrush, Mormon tea, indigo bush, honey mesquite, and brittlebush are associated shrubs. Yucca, prickly pear, and Joshua tree are also present (Cronquist, 1972).
A much smaller, but more productive rangeland component is the mountain shrubs zone. Mountain shrubs occupy almost 1.2 million acres, generally at elevations above 6,500 feet. Unlike the lower sagebrush and salt desert scrub zones, this vegetation zone has eluded major vegetation conversions and remains in relatively good condition. Serviceberry, snowberry, currant, bitterbrush, are present throughout. Unique shrub species in the Sierra Nevada ecoregion include varieties of manzanita, tobaccobrush and other species in the Ceanothus genera, and chinquapin. Patches of mountain mahogany, aspen, and conifers are common. The moister and cooler conditions at upper elevations help to sustain the vigor of native plants, giving them an edge over aggressive annual grasses and weeds. More moderate environmental conditions also dampen the risk of large and severe wildfires. Pinyon pine and juniper stands are expanding in central and eastern Nevada and in some locations crowding out the shrub and grass understory. Overcrowded woodlands reduce forage, creating competition among big game population and livestock herds. Mechanical thinning and prescribed fire are among the alternative measures being used to manage pygmy conifers.
Sagebrush dominates the state, with subtly different shrub communities spanning 30.5 million acres. One or more of the twelve species and subspecies of sagebrush dominates over half of the state's rangeland. The sagebrush/perennial grass (also known as sagebrush steppe) and Great Basin sagebrush ecosystems are the two dominant types. Mountain sagebrush is prevalent above 6,500 feet in central and northern Nevada. Sagebrush steppe is more common in the Columbia Plateau ecoregion and mid-elevations in the central mountains in semi-arid microclimates. Associated shrubs may include bitterbrush, rabbitbrush, currant, gooseberry or cliffrose. Grasses make up a significant portion of the steppe plant mix. The Great Basin sagebrush zone typically occurs above 4,500 feet and native grass species make a small percentage of the understory or do not occur at all. An exception is areas invaded by cheatgrass. Stands of juniper, pinyon pine, and possibly Jeffrey or ponderosa pine are intermixed. This lower elevation sagebrush ecosystem is the most widespread and abundant cover type in Nevada.
Scientists uncovering the natural prehistory of Nevada's ecoregions have found that rangeland plant communities were adapted to light to moderate grazing by comparatively small populations of large and small herbivores (e.g., pronghorn antelope, mule deer,  elk, bighorn sheep, jack and cottontail rabbits) (Grayson, 1993). Other major influences on vegetation include human harvesting practices and frequency of natural and human-set fires.
Given the low population densities and seasonal movements, native populations food gathering and use of fire likely affected only a small fraction of the landscape (Griffen, 2002). Since settlement, domestic livestock grazing has been the primary use of rangelands. The BLM and USFS combined manage about 85 percent of the rangeland areas in the state. Cattle and sheep production on public rangeland is managed within grazing allotments by permittees and agency resource scientists.
In 1999, the BLM held 700 permits for livestock grazing on 45 million acres of the 48 million acres administered by the agency (U.S. Bureau of Land Management, 2000). On Humboldt-Toiyabe National Forest (HTNF) land, the USFS administered 298 grazing allotments covering 4.7 million acres of the total 5.8 million acres in the national forest (Humboldt-Toiyabe National Forest, 2001). The allotment and acreage totals include HTNF land in Nevada and California, of which 92 percent lies in Nevada.
The arid climate, low annual forage production, and the small amount of private holdings with sufficient area to make livestock operations economically viable requires the use of forage resources available on surrounding public lands. Almost all of the cattle and sheep raised in Nevada are produced on ranches that make some use of public rangelands. The non-federal component of rangeland used for livestock grazing livestock is significant (Table 4-2).
The total amount of nonfederal rangeland used for grazing has changed little since the early 1980's, but grazing on pasture and forestland has decreased (U.S. Natural Resources Conservation Service, 2000). Private ranch land contains valuable water resources and riparian habitat, and therefore is important to maintaining healthy watersheds. Livestock operations either own or lease private land and get a BLM and/or USFS permit for the federal public land. Compared with other states, Nevada ranches, supplemented with public grazing land, are large but capable of continuously supporting relatively small numbers of livestock.
The BLM manages and monitors forage and ecological conditions. Forage production and utilization (i.e., proportion of plants removed) traditionally has been the focus of monitoring. In recent years, ecological site condition monitoring is being performed more often. Ecological site condition monitoring is based on a comparison of existing soil, vegetation, wildlife, and physical site conditions to more natural conditions. The data from monitoring are used to evaluate post- or pre-grazing carrying capacity, select grazing management practices, and set priorities for special range improvement activities on public lands.
To be consistent with multiple use principles, the BLM allocates available forage to each class of grazing animal, including domestic cattle and sheep, mule deer, elk, bighorn sheep, pronghorn antelope, and wild horses and burros. The BLM in 1999 used the combined results from ecological site and forage condition monitoring to characterize rangeland conditions.
Of the 45 million acres covered under grazing allotments, five percent was rated in excellent condition and 12 percent poor (Figure 4-2). About 21 million allotment acres were rated as fair to poor (47 percent) and 13.6 million acres as good to excellent (13.6 percent). Grazing, fires, and nonnative plants are factors in the proportionately large amount of grazed rangeland in fair to poor condition (U.S. Bureau of Land Management, 2000)
Historically, cattle and sheep repeatedly grazed sagebrush, salt desert shrub, mountain shrub, and riparian zones, exhausting the regenerative capacity of native grass and shrub species. Though improvements in grazing management practices have been made throughout the state, harsh environmental conditions have slowed recovery of the natural vegetation. Ultimately, the extensive removal of perennial grasses substantially changed the sagebrush zone. Thickening shrub canopies and cheat grass understory have filled the voids. The flammability of cheat grass and closure of the shrub canopy has created conditions favorable to wildfire (Young, 1985).
During the 1999 and 2000 fire seasons, wildfires consumed more than one million acres in the sagebrush zone. The intensity of some fires completely destroyed much of the vegetation within burned areas and seeds stored in the upper soil layer. Without native seed sources nearby, burned sagebrush habitats are not capable of natural regeneration, and therefore more susceptible to invasion by non-native plants. The spread of noxious weeds, some of which have been present in small numbers for decades, appears to have accelerated in recent years. In some areas, the numbers of livestock may still exceed the carrying capacity of rangeland plant communities. Less vegetative cover and fewer deep rooted plants increases runoff and accelerates erosion, contributing to the high sediment and nutrient loads in water quality impaired reaches of major rivers.
A related concern is the effects of wildfire on the distribution and abundance of vegetation consumed by game animals, livestock, and wild horses. Competition among the large grazing animals is likely to further degrade sagebrush ecosystems unless animal numbers are managed in proportion to acres of habitat burned. Wildfire and resulting overgrazing can impair living conditions for sensitive species as well. Special status wildlife species dependent on sagebrush habitats include the Sage Grouse, Burrowing Owl, Mountain Quail, Brewer's Sparrow, pygmy rabbit, sagebrush vole, and the sagebrush lizard.
The deterioration and conversion of millions of acres of sagebrush, riparian and other rangeland communities is a serious ecological event. The intensity of concern is evident in the number of agencies, scientists, and interest groups working on special collaborative studies and planning efforts involving restoration of sagebrush ecosystems. High profile cooperative efforts mentioned previously that focus on the sagebrush vegetation zone at-large include the Great Basin Restoration Initiative, sponsored by the BLM, and state sponsored initiatives for sage grouse conservation, fire management, and invasive weed control.
Rangeland areas are undergoing more permanent changes too. Rangeland made up 78 percent of the total land in Nevada developed for residential, commercial, industrial, utility, and transportation uses from 1992 to 1997. Though the amount of land converted is less than 0.5 percent of the total rangeland area, other associated activities extend the influence of development beyond building footprints. Solid waste  disposal; illegal dumping; hiking, biking, and motorized recreation trails; and, road and utility corridor construction are examples. Mining also constitutes a substantial and expanding use of Nevada's rangeland. However, information on the amount of rangeland converted for historic and contemporary mineral development was not available.
The use and management of public rangeland resources is becoming more challenging with the growing number and diversity of public land users. On today's federal public rangeland menu are livestock grazing, dozens of outdoor recreation pursuits, wildlife habitat, riparian management, endangered species management, mining, hunting, cultural resource protection, wilderness, wild horse and burro habitat, energy development, and various special uses.
Administration of large land areas is especially challenging as national offices of federal agencies make frequent changes in policies and enforcement of regulations. Meeting the multiple use mandate has created divisiveness in Nevada where competition among incompatible land use activities is high.
Public pressure from interests on all sides has required the agencies to open up their land use and resource planning processes, sometimes slowing down the decision making process. Because such a vast amount and diversity of Nevada's natural resources are found on the rangeland, special care is warranted in land management decisions. Investment in restoration of deteriorated conditions is vital to the future of agriculture, wildlife, and the quality of outdoor recreation experiences in Nevada.
 Next Page -- Forestland
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