Natural Resources
Conservation Service
-
Search
Major Land Resource Area or ecological site by name and/or ID.
PreviousSectionsNextGeneral information
Draft. A draft ecological site description is either incomplete or has not undergone quality control and quality assurance review.
MLRA notes
Major Land Resource Area (MLRA): 028A–Ancient Lake Bonneville
MLRA 28A occurs in Utah (82%), Nevada (16%), and Idaho (2%). It makes up about 36,775 square miles (95,300 square kilometers). About three-fifths of this area is federally owned land, large tracts of which are used for military training and testing purposes by the. A large area west and southwest of Great Salt Lake is a salty playa. This area is the farthest eastern extent of the Great Basin Section of the Basin and Range Province of the Intermontane Plateaus. It is an area of nearly level basins between widely separated mountain ranges trending north to south. The basins are bordered by long, gently sloping alluvial fans. The mountains are uplifted fault blocks with steep side slopes. They are not well dissected because of low rainfall in the MLRA. Most of the valleys are closed basins containing sinks or playa lakes. Elevation ranges from 3,950 to 6,560 feet (1,205 to 2,000 meters) in the basins and from 6,560 to 11,150 feet (2,000 to 3,400 meters) in the mountains.
Most of this area has alluvial valley fill and playa lakebed deposits at the surface. Great Salt Lake is all that remains of glacial Lake Bonneville, which covered this area during the most recent ice age. A level line on some mountain slopes indicates the former extent of this glacial lake. The uplifted mountains have exposed some Precambrian rocks at their margins. Most of the mountains in the interior of this area consist of tilted blocks of marine sediments from Cambrian to Mississippian age. Scattered outcrops of Tertiary continental sediments and volcanic rocks are throughout the area.
The average annual precipitation is 5 to 12 inches (125 to 305 millimeters) in the valleys and is as much as 49 inches (1,245 millimeters) in the mountains. Most of the rainfall occurs as high-intensity, convective thunderstorms during the growing season. The driest period is from midsummer to early autumn. Precipitation in winter typically occurs as snow. The average annual temperature is 39 to 53 degrees F (4 to 12 degrees C). The freeze-free period averages 165 days and ranges from 110 to 215 days, decreasing in length with elevation.
The dominant soil orders in this MLRA are Aridisols, Entisols, and Mollisols. The soils in the area dominantly have a mesic or frigid soil temperature regime, an aridic or xeric soil moisture regime, and mixed mineralogy. They generally are well drained or somewhat excessively drained, loamy or loamy-skeletal, and very deep.
Ecological site concept
This site occurs on sideslopes of hill and mountains on all exposures. Slopes range from 8 to over 50 percent, but are typically 30 to 50 percent. Elevations are 5800 to 8500 feet.
Average annual precipitation is 12 to 14 inches. Mean annual air temperature is 43 to 45 degrees F. The average growing season is 85 to 100 days.
Soils associated with this site are shallow to bedrock. These soils have formed in colluvium from welded tuff sources. The soils are skeletal, with 35 to over 75 percent rock fragments (by volume) distributed through the soil profile. Available water capacity is very low but trees and shrubs can extend their roots into fractures in bedrock allowing them to utilize deep moisture.
The reference state is dominated by singleleaf pinyon and Utah juniper. Mountain big sagebrush is the principal understory shrub. Bluebunch wheatgrass and muttongrass are the most prevalent understory grasses.
An overstory canopy of 20 to 35 percent is assumed to be representative of tree dominance on this site in the reference plant community. Wildfire is recognized as a natural disturbance that strongly influenced the structure and composition of the climax vegetation of this forestland site. Overstory tree canopy composition is about 50 to 70 percent Utah juniper and about 30 to 50 percent singleleaf pinyon. Production ranges from 300 to 700 pounds per acre.Associated sites
F028AY075NV PIMO-JUOS/ARAR8/PSSPS-POFE
R028AY062NV MOUNTAIN RIDGE
R028AY088NV GRAVELLY CLAY 12-14 P.Z.
R028AY126NV COBBLY CLAYPAN 12-14 P.Z.
Similar sites
F028AY076NV PIMO/ARTRV/PSSPS-POFE
Lower site index. Less understory production.
F028AY077NV PIMO-CELE3/ARTRV/PSSPS-POFE
Higher site index. Curlleaf mountain mahogany common in the overstory. Less understory production.
Table 1. Dominant plant species
Tree (1) Pinus monophylla
(2) Juniperus osteospermaShrub (1) Artemisia tridentata subsp. vaseyana
Herbaceous (1) Pseudoroegneria spicata subsp. spicata
(2) Poa fendlerianaPhysiographic features
This site occurs sideslope of hills and mountains on all exposures. Slopes range from 8 to over 50 percent, but are typically 30 to 50 percent. Elevations are 5800 to 8500 feet.
Table 2. Representative physiographic features
Landforms (1) Mountain slope
(2) Hill
Elevation 5800 – 8500 ft Slope 8 – 50 % Aspect Aspect is not a significant factor Climatic features
Nevada’s climate is predominantly arid, with large daily ranges of temperature, infrequent severe storms, heavy snowfall in the higher mountains, and great location variations with elevation. Three basic geographical factors largely influence Nevada’s climate: continentality, latitude, and elevation. Continentality is the most important factor. The strong continental effect is expressed in the form of both dryness and large temperature variations. Nevada lies on the eastern, lee side of the Sierra Nevada Range, a massive mountain barrier that markedly influences the climate of the State. The prevailing winds are from the west, and as the warm moist air from the Pacific Ocean ascend the western slopes of the Sierra Range, the air cools, condensation occurs and most of the moisture falls as precipitation. As the air descends the eastern slope, it is warmed by compression, and very little precipitation occurs. The effects of this mountain barrier are felt not only in the West but throughout the state, with the result that the lowlands of Nevada are largely desert or steppes. The temperature regime is also affected by the blocking of the inland-moving maritime air. Nevada sheltered from maritime winds, has a continental climate with well-developed seasons and the terrain responds quickly to changes in solar heating.
Nevada lies within the mid-latitude belt of prevailing westerly winds which occur most of the year. These winds bring frequent changes in weather during the late fall, winter and spring months, when most of the precipitation occurs. To the south of the mid-latitude westerlies, lies a zone of high pressure in subtropical latitudes, with a center over the Pacific Ocean. In the summer, this high-pressure belt shifts northward over the latitudes of Nevada, blocking storms from the ocean. The resulting weather is mostly clear and dry during the summer and early fall, with scattered thundershowers. The eastern portion of the state receives significant summer thunderstorms generated from monsoonal moisture pushed up from the Gulf of California, known as the North American monsoon. The monsoon system peaks in August and by October the monsoon high over the Western U.S. begins to weaken and the precipitation retreats southward towards the tropics (NOAA 2004).
Average annual precipitation is 12 to 14 inches. Mean annual air temperature is 43 to 45 degrees F. The average growing season is 70 to 100 days.
Mean annual precipitation at the GREAT BASIN NATL PARK,NEVADA climate station (263340) is 13.33 inches.
monthly mean precipitation is:
January 1.05; February 1.18; March 1.37; April 1.21;
May 1.24; June 0.87; July 0.97; August 1.18;
September 1.08; October 1.24;
November 0.97; December 0.96.Table 3 Representative climatic features
Frost-free period (average) 80 days Freeze-free period (average) 150 days Precipitation total (average) 10 in BarLineFigure 1. Monthly precipitation range
BarLineFigure 2. Monthly average minimum and maximum temperature
Figure 3. Annual precipitation pattern
Figure 4 Annual average temperature pattern
Climate stations used
-
(1) GREAT BASIN NP [USC00263340], Baker, NV
">Influencing water features
There are no influencing water features associated with this site.
Soil features
Soils associated with this site are shallow and well drained. These soils have formed in colluvium from welded tuff sources or quartzite and slate. The soil temperature regime is frigid and the soil moisture regime is aridic bordering on xeric. The soils have an argillic horizon and a thin (7 inches) mollic epipedon. The soils are skeletal, with 35 to over 60 percent rock fragments (by volume) distributed through the soil profile. Available water capacity is very low but trees and shrubs can extend their roots into fractures in bedrock allowing them to utilize deep moisture. These soils normally have high amounts of gravels, stones or cobbles on the surface that occupy plant growing space, yet help to reduce evaporation and conserve soil moisture. Rock fragments on the surface provide a stabilizing affect on surface erosion conditions. Runoff is medium to very high. The soil series associated with this site include: Farepeak and Grandeposit.
The representative soil component is Farepeak (NV784, MU4020), classified as an Ashy-skeletal, glassy, frigid Aridic Lithic Argixerolls. Diagnostic horizons include a mollic epipedon from the soil surface to 13 inches and an argillic horizon from 3 to 13 inches. Depth to bedrock is 10 to 14 inches. Clay content in the particle control sections average 27 to 35 percent. Rock fragments range from 35 to 60 percent mainly gravel. Reaction is slightly alkaline or moderately alkaline. Effervescence is none. Lithology consists of welded tuff.Table 4. Representative soil features
Parent material (1) Residuum – welded tuff
(2) Colluvium – quartzite
Surface texture (1) Very cobbly loam
(2) Very gravelly loam
Family particle size (1) Loamy
Drainage class Well drained Permeability class Moderately slow to moderate Soil depth 10 – 20 in Surface fragment cover <=3" 23 – 40 % Surface fragment cover >3" 5 – 50 % Available water capacity
(0-40in)1.5 – 1.9 in Calcium carbonate equivalent
(0-40in)0 – 1 % Electrical conductivity
(0-40in)Not specified Sodium adsorption ratio
(0-40in)Not specified Soil reaction (1:1 water)
(0-40in)6.9 – 8 Subsurface fragment volume <=3"
(Depth not specified)23 – 50 % Subsurface fragment volume >3"
(Depth not specified)5 – 48 % Ecological dynamics
Ecological Dynamics:
An ecological site is the product of all the environmental factors responsible for its development and has a set of key characteristics that influence a site’s resilience to disturbance and resistance to invasives. Key characteristics include 1) climate (precipitation, temperature), 2) topography (aspect, slope, elevation, and landform), 3) hydrology (infiltration, runoff), 4) soils (depth, texture, structure, organic matter), 5) plant communities (functional groups, productivity), and 6) natural disturbance regime (fire, herbivory, etc.) (Caudle et al. 2003). Biotic factors that influence resilience include site productivity, species composition and structure, and population regulation and regeneration (Chambers et al. 2013).
Pinyon- and juniper-dominated plant communities in the cold desert of the Intermountain West occupy over 18 million ha (44,600,000 acres) (Miller and Tausch 2001). In the mid to late 1900’s, the number of pinyon and juniper trees establishing per decade began to increase compared to the previous several hundred years. The substantial increase in conifer establishment is attributed to a number of factors, the most important being: (1) cessation of the aboriginal burning (Tausch 1999), (2) change in climate with rising temperatures (Heyerdahl et al. 2006), (3) the reduced frequency of fire likely driven by the introduction of domestic livestock, (4) a decrease in wildfire frequency along with improved wildfire suppression efforts and (5) potentially increased CO2 levels favoring woody plant establishment (Tausch 1999, Bunting 1994). Miller et al. (2008) found presettlement tree densities averaged 2 to 11 per acre in six woodlands studied across the Intermountain West. Current stand densities range from 80 to 358 trees/ac. In Utah, Nevada, and Oregon, trees established prior to 1860 account for only 2 percent or less of the total population of pinyon and juniper (Miller et al. 2008). The research strongly suggests that for over 200 years prior to settlement, woodlands in the Great Basin were relatively low density with limited rates of establishment (Miller et al. 2008, Miller and Tausch 2001). Tree canopy cover of 10 to 20% may be more representative of these sites in pristine condition. Increases in pinyon and juniper densities post-settlement were the result of both infill in mixed age tree communities and expansion into shrub-steppe communities. Pre-settlement trees accounted for less than 2 percent of the stands sampled in Nevada, Oregon and Utah (Miller et al. 2008, Miller and Tausch 2001, Miller et al. 1999). However, the proportion of old-growth can vary depending on disturbance regimes, soils and climate. Some ecological sites are capable of supporting persistent woodlands, likely due to specific soils and climate resulting in infrequent stand replacement disturbance regimes. In the Great Basin, old-growth trees have been found to typically grow on rocky shallow or sandy soils that support little understory vegetation to carry a fire (Holmes et al. 1986, Miller and Rose 1995, West et al. 1998).
Singleleaf pinyon and Utah juniper are long-lived tree species with wide ecological amplitudes (Tausch et al 1981, Weisberg and Dongwook 2012, West et al 1998). Maximum ages of pinyon and juniper exceed 1000 years and stands with maximum age classes are only found on steep rocky slopes with no evidence of fire (West et al 1975). Singleleaf pinyon is slow-growing and very intolerant to shade with the exception of young plants, usually first year seedlings (Tueller and Clark 1975). Singleleaf pinyon seedling establishment is episodic. Population age structure is affected by drought, which reduces seedling and sapling recruitment more than other age classes. The ecotones between singleleaf pinyon woodlands and adjacent shrublands and grasslands provide favorable microhabitats for singleleaf pinyon seedling establishment since they are active zones for seed dispersal, nurse plants are available, and singleleaf pinyon seedlings are only affected by competition from grass and other herbaceous vegetation for a couple of years.
Pinyon and juniper growth is dependent mostly upon soil moisture stored from winter precipitation, mainly snow. Much of the summer precipitation is ineffective, being lost in runoff after summer convection storms or by evaporation and interception (Tueller and Clark 1975). Pinyon and juniper are highly resistant to drought which are common in the Great Basin. Tap roots of pinyon and juniper have a relatively rapid rate of root elongation and are thus able to persist until precipitation conditions are more favorable (Emerson 1932).
Infilling by younger trees increases canopy cover causing a decrease in understory perennial vegetation and an increase in bare ground. As pinyon and juniper trees increase in density so has their litter. Phenolic compounds of juniper scales can have an inhibitory effect on grass growth (Jameson 1970). Furthermore, infilling shifts stand level biomass from ground fuels to canopy fuels which has the potential to significantly impact fire behavior. The more tree dominated pinyon and juniper woodlands become, the less likely they are to burn under moderate conditions, resulting in infrequent high intensity fires (Gruell 1999, Miller et al. 2008). Additionally, as the understory vegetation declines in vigor and density with increased canopy the seed and propagules of the understory plant community also decrease significantly. The increase in bare ground allows for the invasion of non-native annual species such as cheatgrass and with intensive wildfire the potential for conversion to annual exotics is a serious threat (Tausch 1999, Miller et al. 2008).
Specific successional pathways after disturbance in pinyon-juniper stands are dependent on a number of variables such as plant species present at the time of disturbance and their individual responses to disturbance, past management, type and size of disturbance, available seed sources in the soil or adjacent areas, and site and climatic conditions throughout the successional process.
Utah juniper can be killed by a fungus called Juniper Pocket Rot (Pyrofomes demidoffi), also known as white truck rot (Eddleman et al. 1994 and Durham 2014). Pocket rot enters the tree through any wound or opening that exposes the heartwood. In an advanced stage, this fungus can cause high mortality (Durham 2014). Dwarf mistletoe (Phorandendron spp.) a parasitic plant, may also affect Utah juniper and without treatment or pruning, may kill the tree 10-15 years after infection. Seedlings and saplings are most susceptible to the parasite (Christopherson 2014). Other diseases capable of affecting juniper include: witches’-broom (Gymnosporangium sp.), which may girdle and kill branches; leaf rust (Gymnosporangium sp.) on leaves and young branches; and juniper blight (Phomopsis sp.). Insections include: flat-head borers (Chrysobothris sp.) that attack the wood; long-horned beetles (Methia juniper, Styloxus bicolor) that girdle limbs and twigs; and round-head borers (Callidium spp.) that attack twigs and limbs (Tueller and Clark 1975).
Phillips (1909) recognized that the pinyons are more resistant to disease than most of the conifers with which it associates. Hepting (1971) lists several diseases affecting pinyon including: foliage diseases, a tarspot needle cast, stem diseases such as blister rust and dwarf mistletoe, root diseases and trunk rots, red heart rot, and but rot. The pinyon ips beetle (Ips confuses) and pinyon needle scale (Matsucoccus acalyptus) are both native insects to Nevada that attack pinyon pines throughout their range. The pinyon needle scale weakens trees by killing needles older than 1 year. Sometimes small trees are killed by repeated feeding and large trees are weakened to the point that they are attacked by the pinyon ips beetle. The beetle typically kills weak and damaged trees (Phillips 2014). During periods of chronic drought the impact of these two insects on singleleaf pinyon can be substantial.
The perennial bunchgrasses that are co-dominant with the shrubs include bluebunch wheatgrass and muttongrass. Other common grasses include Indian ricegrass, Sandberg bluegrass (Poa secunda), blue grama (Bouteloua gracilis), squirreltail (Elymus elymoides) and basin wildrye (Leymus cinereus). These species generally have somewhat shallower root systems than the shrubs, but root densities are often as high as or higher than those of shrubs in the upper 0.5 m but taper off more rapidly than shrubs. Differences in root depth distributions between grasses and shrubs result in resource partitioning in these shrub/grass systems.
Mountain big sagebrush and antelope bitterbrush are generally long-lived; therefore it is not necessary for new individuals to recruit every year for perpetuation of the stand. Infrequent large recruitment events and simultaneous low, continuous recruitment is the foundation of population maintenance (Noy-Meir 1973). Survival of the seedlings is dependent on adequate moisture conditions. Antelope bitterbrush is most commonly found on soils which provide minimal restriction to deep root penetration such as coarse textured soil, or finer textured soil with high stone content (Driscoll 1964, Clements and Young 2002).
This ecological site has low to moderate resilience to disturbance and resistance to invasion. Resilience increases with elevation, aspect, increased precipitation and increased nutrient availability. Three possible alternative stable states have been identified for this site.
Fire Ecology:
Lightning-ignited fires were common but typically did not affect more than a few individual trees. Replacement fires were uncommon to rare (100-600 years) and occurred primarily during extreme fire behavior conditions. Spreading, low-intensity surface fires had a very limited role in molding stand structure and dynamics. Surface spread was more likely to occur in higher-density woodlands growing on more productive sites (Romme et al 2007). Pre-settlement fire return intervals in the Great Basin National Park, Nevada were found to have a mean range between 50 to 100 years with north-facing slopes burning every 15 to 20 years and rocky landscapes with sparse understory very infrequently (Gruell 1999). Woodland dynamics are largely attributed to long-term climatic shifts (temperature, amounts and distribution of precipitation) and the extent and return intervals of fire (Miller and Tausch 2001). Limited data exists that describes fire histories across woodlands in the Great Basin. The infilling of younger trees into the old-growth stands and the expansion of trees into the surrounding sagebrush steppe ecological sites has increased the risk of loss of pre-settlement trees due to increased fire severity and size resulting from the increase in the abundance and landscape level continuity of fuels (Miller et al. 2008).
Utah juniper is usually killed by fire, and is most vulnerable to fire when it is under four feet tall (Bradley et al. 1992). Larger trees, because they have foliage farther from the ground and thicker bark, can survive low severity fires but mortality does occur when 60% or more of the crown is scorched (Bradley et al. 1992). Singleleaf pinyons are also most vulnerable to fire when less than four feet tall, however mature trees do not self-prune their dead branches allowing for accumulated fuel in the crowns. This characteristic and the relative flammability of the foliage make individual mature trees susceptible to fire (Bradley et al. 1992). With the low production of the understory vegetation and low density of trees per acre, high severity fires within this plant community were not likely and rarely became crown fires (Bradley et al. 1992, Miller and Tausch 2001).
Singleleaf pinyon and Utah juniper reestablish by seed from nearby seed sources or surviving seeds. Junipers have a long-lived seed bank due to delayed germination by impermeable seed coats, immature or dormant embryos and germination inhibitors (Chambers et al. 1999). Singleleaf pinyon trees have relatively short-lived seeds with little innate dormancy that form only temporary seed banks with most seeds germinating the spring following dispersal (Meewig and Bassett 1983). Density of pinyon seeds in the seed bank is dependent upon the current year’s cone crop. Singleleaf pinyon are known to have favorable cone production every two to three years thus the potential for a large temporary seed bank is high during mast years and likely low during non-mast years (Chambers et al. 1999). The role of nurse plant requirements between the two tree species is important to post-fire establishment. Chambers et al. (1999) found that singleleaf pinyon seedlings rarely establish in interspaces or open environments. In contrast, Utah juniper seedlings were found capable of establishing in interspace microhabitats as frequently as under sagebrush. Therefore, fire that removes both trees and understory shrubs in pinyon-juniper woodlands may have a relatively greater effect on the establishment of pinyon than juniper.
Initial response of native understory species following fire correlates closely with percent crown cover. In general, research indicates that understory response to disturbance is most productive when crown cover is at or below 20% while beyond 30% there is a rapid decline in understory species and soil seed reserves (Huber et al. 1999).
Mountain big sagebrush is killed by fire (Neuenschwander 1980, Blaisdell et al. 1982) and does not resprout (Blaisdell 1953). Post fire regeneration occurs from seed and will vary depending on site characteristics, seed source, and fire characteristics. Mountain big sagebrush seedlings can grow rapidly and may reach reproductive maturity within 3 to 5 years (Bunting et al. 1987). Mountain big sagebrush may return to pre-burn density and cover within 15-20 years following fire, but establishment after severe fires may proceed more slowly (Bunting et al. 1987).
Antelope bitterbrush is moderately fire tolerant (McConnell and Smith 1977). It regenerates by seed and resprouting (Blaisdell and Mueggler 1956, McArthur et al. 1982), though sprouting ability is highly variable and has been attributed to genetics, plant age, phenology, soil moisture and texture, and fire severity (Blaisdell and Mueggler 1956, Blaisdell et al. 1982, Clark et al. 1982, Cook et al. 1994). Bitterbrush sprouts from a region on the stem approximately 1.5 inches above and below the soil surface; the plant rarely sprouts if the root crown is killed by fire (Blaisdell and Mueggler 1956). Low intensity fires may allow for bitterbrush to sprout; however, community response also depends on soil moisture levels at time of fire (Murray 1983). Lower soil moisture allows more charring of the stem below ground level (Blaisdell and Mueggler 1956), thus sprouting will usually be more successful after a spring fire than after a fire in summer or fall (Murray 1983, Busse et al. 2000, Kerns et al. 2006). If cheatgrass is present, bitterbrush seedling success is much lower. The factor that most limits establishment of bitterbrush seedlings is competition for water resources with cheatgrass, an invasive species (Clements and Young 2002).
The effect of fire on bunchgrasses relates to culm density, culm-leaf morphology, and the size of the plant. The initial condition of bunchgrasses within the site along with seasonality and intensity of the fire factor into the individual species’ responses. For most forbs and grasses, the growing points are located at or below the soil surface, providing relative protection from disturbances which decrease above ground biomass, such as grazing or fire. Thus, fire mortality is more correlated to duration and intensity of heat (Wright 1971, Young 1983). Season and severity of the fire will also influence plant response, which will vary depending on post-fire soil moisture availability.
Fire will remove aboveground biomass from bluebunch wheatgrass but plant mortality is generally low (Robberecht and Defossé 1995) because the buds are underground (Conrad and Poulton 1966) or protected by foliage. Uresk et al. (1976) reported burning increased vegetative and reproductive vigor of bluebunch wheatgrass. Thus, bluebunch wheatgrass is considered to experience slight damage to fire but is more susceptible in drought years (Young 1983). Plant response will vary depending on season, fire severity, fire intensity and post-fire soil moisture availability.
Indian ricegrass is fairly fire tolerant (Wright 1985), which is likely due to its low culm density and below ground plant crowns. Vallentine (1989) cites several studies in the sagebrush zone that classified Indian ricegrass as being slightly damaged from late summer burning. Indian ricegrass has also been found to reestablish on burned sites through seed dispersed from adjacent unburned areas (Young 1983, West 1994). Thus the presence of surviving, seed producing plants facilitates the reestablishment of Indian ricegrass. Grazing management following fire to promote seed production and establishment of seedlings is important.
Sandberg bluegrass (Poa secunda) a minor component of this ecological site, has been found to increase following fire likely due to its low stature and productivity (Daubenmire 1975). Sandberg bluegrass may retard reestablishment of deeper rooted bunchgrass.
Muttongrass is top killed by fire but will resprout after low to moderate severity fires. A study by Vose and White (1991) in an open sawtimber site found minimal difference in overall effect of burning on mutton grass.State and transition model
Custom diagramStandard diagram
Figure 5. State and Transition Model
Figure 6. Legend
More interactive model formats are also available. View Interactive Models
More interactive model formats are also available. View Interactive Models
Click on state and transition labels to scroll to the respective textEcosystem states
State 1 submodel, plant communities
State 2 submodel, plant communities
State 3 submodel, plant communities
State 4 submodel, plant communities
State 1
Reference StateReference State 1.0: The Reference State 1.0 is representative of the natural range of variability under pristine conditions. This Reference State has four general community phases: an old-growth woodland phase, a shrub-herbaceous phase, an immature tree phase, and an infilled tree phase. State dynamics are maintained by interactions between climatic patterns and disturbance regimes. Negative feedbacks enhance ecosystem resilience and contribute to the stability of the state. These include the presence of all structural and functional groups, low fine fuel loads, and retention of organic matter and nutrients. Plant community phase changes are primarily driven by fire, periodic drought, and/or insect or disease attack.
Community 1.1
Community PhaseThe plant community is dominated by singleleaf pinyon and Utah juniper. Mountain big sagebrush is the principal understory shrub. Bluebunch wheatgrass and muttongrass are the most prevalent understory grasses.
An overstory canopy of 20 to 30 percent is assumed to be representative of tree dominance on this site in the reference plant community. Wildfire is recognized as a natural disturbance that strongly influenced the structure and composition of the climax vegetation of this site. Overstory tree canopy composition is about 50 to 70 percent Utah juniper and about 30 to 50 percent singleleaf pinyon.Forest overstory.OLD GROWTH: The visual aspect and vegetal structure are dominated by pinyon and juniper that have reached maximal heights for the site. Dominant trees average greater than five inches in diameter at one-foot stump height. Upper crowns of singleleaf pinyon and Utah juniper are typically either irregularly or smoothly flat-topped or rounded. Tree canopy cover ranges from 20 to 35 percent. Understory vegetation is strongly influenced by tree competition, overstory shading, duff accumulation, etc. Few tree seedlings and/or saplings occur in the understory. Infrequent, yet periodic, wildfire is a natural disturbance influencing the understory of mature pinyon-juniper forestlands. This stage of community development is assumed to be representative of this forestland site in the pristine environment.
Forest understory. Understory vegetative composition is about 60 percent grasses, 10 percent forbs and 30 percent shrubs and young trees when the average overstory canopy is medium (about 30 percent). Average understory production ranges from 300 to 700 pounds per acre with a medium canopy cover. Understory production includes the total annual production of all species within 4½ feet of the ground surface.
Figure 7. Annual production by plant type (representative values) or group (midpoint values)
Table 5. Annual production by plant type
Plant type Low
(lb/acre)Representative value
(lb/acre)High
(lb/acre)Grass/Grasslike 150 250 350 Shrub/Vine 90 150 210 Forb 30 50 70 Tree 30 50 70 Total 300 500 700 Community 1.2
Community PhaseThis community phase is characterized by a post-fire shrub and herbaceous community. Sprouting shrubs, bluebunch wheatgrass and other perennial grasses dominate. Forbs may increase post-fire but will likely return to pre-burn levels within a few years. Singleleaf pinyon and Utah juniper seedlings up to 20 inches in height may be present. Mountain big sagebrush may be present in unburned patches. Burned tree skeletons may be present; however these have little or no effect on the understory vegetation.
Forest overstory. This stage is experienced after a major disturbance such as crown fire or tree harvest. Skeleton forest (dead trees) remaining after fire or residual trees left following harvest have little affect on the composition and production of the herbaceous vegetation.Various amounts of tree seedlings (less than 20 inches in height) may be present up to the point where they are obviously a major component of the vegetal structure.
Forest understory. Vegetation is dominated by sprouting shrubs, grasses and forbs under full sunlight. Understory production ranges from 600 to 1200 pounds per acre.
Community 1.3
Community PhaseThis community phase is characterized as an immature woodland with singleleaf pinyon and Utah juniper trees averaging over 4.5 feet in height. Pinyon and juniper canopy cover is between 10 to 20 percent. Tree crowns are typically cone- or pyramidal-shaped. Understory vegetation consists of smaller tree seedling and saplings, as well as perennial bunchgrasses and sagebrush.
Forest overstory.IMMATURE FORESTLAND: The visual aspect and vegetal structure are dominated by Utah juniper and singleleaf pinyon trees greater than 4.5 feet in height. The upper crown of dominant and co-dominant trees are cone or pyramidal shaped. Seedlings and saplings of pinyon and Utah juniper are present in the understory. Dominants are the tallest trees on the site; co-dominants are 65 to 85 percent of the highest of dominant trees. Understory vegetation is moderately influenced by a tree overstory canopy of about 10 to 20 percent.
Forest understory. The understory is a mix of shrubs, grasses and forbs. Production ranges from 500 to 900 pounds per acre.
Community 1.4
Community PhaseThis phase is dominated by Utah juniper and singleleaf pinyon. The stand exhibits mixed age classes and canopy cover exceeds 20 percent. The density and vigor of the mountain big sagebrush and perennial bunchgrass understory is decreased. Bare ground areas are likely to increase. Mat-forming forbs may increase. This community is at risk of crossing a threshold; without proper management this phase will transition to the infilled woodland state 3.0.
Forest overstory.MATURE FORESTLAND: The visual aspect and vegetal structure are dominated by pinyon and juniper that have reached maximal heights for the site. Dominant trees average greater than five inches in diameter at one-foot stump height. Few tree seedlings and/or saplings occur in the understory. Upper crowns of singleleaf pinyon and Utah juniper are typically either irregularly or smoothly flat-topped or rounded. Tree canopy cover ranges from 20 to 35 percent.
Forest understory. Understory vegetation is strongly influenced by tree competition, overstory shading, duff accumulation, etc. Production ranges from 300 to 700 pounds per acre.
Pathway a
Community 1.1 to 1.2A high-severity crown fire will eliminate or reduce the singleleaf pinyon and Utah juniper overstory and the shrub component. This allows for the perennial bunchgrasses and sprouting shrubs to dominate the site.
Pathway b
Community 1.1 to 1.4Time without disturbance such as fire, drought, or disease will allow for the gradual infilling of singleleaf pinyon and Utah juniper.
Pathway a
Community 1.2 to 1.3Time without disturbance such as fire, drought, or disease will allow for the gradual maturation of the singleleaf pinyon and Utah juniper component. Mountain big sagebrush reestablishes.
Pathway b
Community 1.3 to 1.1Time without disturbance such as fire, drought, or disease will allow for the gradual maturation of singleleaf pinyon and Utah juniper. Infilling by younger trees continues.
Pathway a
Community 1.3 to 1.2Fire reduces or eliminates tree canopy, allowing sprouting shrubs and perennial grasses to dominate the site.
Pathway a
Community 1.4 to 1.1Low intensity fire, insect infestation, or disease kills individual trees within the stand reducing canopy cover to less than 20 percent. Over time young trees mature to replace and maintain the old-growth woodland. The mountain big sagebrush and perennial bunchgrass community increases in density and vigor.
Pathway b
Community 1.4 to 1.2A high-severity crown fire will eliminate or reduce the singleleaf pinyon and Utah juniper overstory and the shrub component which will allow for the sprouting shrubs and perennial bunchgrasses to dominate the site.
State 2
Current Potential StateCurrent Potential State 2.0: This state is similar to the Reference State 1.0, with four general community phases: an old-growth woodland phase, a shrub-herbaceous phase, an immature tree phase, and an infilled tree phase. Ecological function has not changed, however the resiliency of the state has been reduced by the presence of non-native species. These non-natives, particularly cheatgrass, can be highly flammable and promote fire where historically fire had been infrequent. Negative feedbacks enhance ecosystem resilience and contribute to the stability of the state. These include the presence of all structural and functional groups, low fine fuel loads and retention of organic matter and nutrients. Positive feedbacks decrease ecosystem resilience and stability of the state. These include the non-natives’ high seed output, persistent seed bank, rapid growth rate, ability to cross pollinate, and adaptations for seed dispersal. Fires within this community with the small amount of non-native annual species present are likely still small and patchy due to low fuel loads. This fire type will create a plant community mosaic that will include all/most of the following community phases within this state.
Community 2.1
Community PhaseThis phase is characterized by a widely dispersed old-growth Utah juniper and singleleaf pinyon trees with an understory of mountain big sagebrush and perennial bunchgrasses. The visual aspect is dominated by singleleaf pinyon and Utah juniper which make up 10-25% of the overstory canopy cover. Trees have reached maximal or near maximal heights for the site and many tree crowns may be flat- or round-topped. Bluebunch wheatgrass and muttongrass are the most prevalent grasses in the understory. Mountain big sagebrush is the primary understory shrub. Forbs such as phlox, buckwheat, and rockcress are minor components. Annual non-native species are present in trace amounts.
Forest overstory.OLD GROWTH: The visual aspect and vegetal structure are dominated by pinyon and juniper that have reached maximal heights for the site. Dominant trees average greater than five inches in diameter at one-foot stump height. Upper crowns of singleleaf pinyon and Utah juniper are typically either irregularly or smoothly flat-topped or rounded. Tree canopy cover ranges from 20 to 30 percent.
Forest understory. Understory vegetation is strongly influenced by tree competition, overstory shading, duff accumulation, etc. Few tree seedlings and/or saplings occur in the understory. Infrequent, yet periodic, wildfire is a natural disturbance influencing the understory of mature pinyon-juniper woodlands. This stage of community development is assumed to be representative of this forestland site in the pristine environment. Production ranges from 300 to 700 pounds per acre.
Community 2.2
Community PhaseThis community phase is characterized by a post-fire shrub and herbaceous community. Sprouting shrubs, bluebunch wheatgrass and other perennial grasses dominate. Forbs may increase post-fire but will likely return to pre-burn levels within a few years. Pinyon and juniper seedlings up to 20 inches in height may be present. Mountain big sagebrush may be present in unburned patches. Burned tree skeletons may be present; however these have little or no effect on the understory vegetation. Annual non-native species generally respond well after fire and may be stable or increasing within the community.
Forest overstory.This stage is experienced after a major disturbance such as crown fire. Skeleton forest (dead trees) remaining after fire or residual trees left following harvest have little or no affect on the composition and production of the herbaceous vegetation. Various amounts of tree seedlings (less than 20 inches in height) may be present up to the point where they are obviously a major component of the vegetal structure.
Forest understory. Herbaceous vegetation and woody shrubs dominate the site. Production ranges from 600 to 1200 pounds per acre.
Community 2.3
Community PhaseThis community phase is characterized by an immature woodland, with singleleaf pinyon and Utah juniper trees averaging over 4.5 feet in height. Tree canopy cover is between 10 to 20 percent. Tree crowns are typically cone- or pyramidal-shaped. Understory vegetation consists of smaller tree seedling and saplings, as well as perennial bunchgrasses and shrubs. Annual non-native species are present.
Forest overstory.IMMATURE FORESTLAND: The visual aspect and vegetal structure are dominated by Utah juniper and singleleaf pinyon trees greater than 4.5 feet in height. The upper crown of dominant and co-dominant trees are cone or pyramidal shaped. Seedlings and saplings of pinyon and Utah juniper are present in the understory. Dominants are the tallest trees on the site; co-dominants are 65 to 85 percent of the highest of dominant trees. Understory vegetation is moderately influenced by a tree overstory canopy of about 10 to 20 percent.
Forest understory. The understory is a mix of shrubs, grasses and forbs. Production ranges from 500 to 900 pounds per acre.
Community 2.4
Community PhaseThis phase is dominated by singleleaf pinyon and Utah juniper. The stand exhibits mixed age classes and canopy cover exceeds 20 percent. The density and vigor of the mountain big sagebrush and perennial bunchgrass understory is decreased. Bare ground areas are likely to increase. Mat-forming forbs may increase. Annual non-native species are present primarily under tree canopies. This community is at risk of crossing a threshold, without proper management this phase will transition to the infilled tree state 3.0.
Forest overstory.MATURE FORESTLAND: The visual aspect and vegetal structure are dominated by pinyon and juniper that have reached maximal heights for the site. Dominant trees average greater than five inches in diameter at one-foot stump height. Few tree seedlings and/or saplings occur in the understory. Upper crowns of singleleaf pinyon and Utah juniper are typically either irregularly or smoothly flat-topped or rounded. Tree canopy cover ranges from 20 to 35 percent.
Forest understory. Understory vegetation is strongly influenced by tree competition, overstory shading, duff accumulation, etc. Understory production ranges from 300 to 700 pounds per acre.
Pathway a
Community 2.1 to 2.2A high-severity crown fire will eliminate or reduce the singleleaf pinyon and Utah juniper overstory and the shrub component. This allows for the perennial bunchgrasses and sprouting shrub to dominate the site.
Pathway b
Community 2.1 to 2.4Time without disturbance such as fire, drought, or disease will allow for the gradual infilling of singleleaf pinyon and Utah juniper.
Pathway a
Community 2.2 to 2.3Time without disturbance such as fire, drought, or disease will allow for the gradual maturation of the singleleaf pinyon and Utah juniper component. Mountain big sagebrush reestablishes.
Pathway b
Community 2.3 to 2.1Fire reduces or eliminates tree canopy, allowing sprouting shrubs and perennial grasses to dominate the site.
Pathway a
Community 2.3 to 2.2Time without disturbance such as fire, drought, or disease will allow for the gradual maturation of singleleaf pinyon and Utah juniper. Infilling by younger trees continues.
Pathway a
Community 2.4 to 2.1Low intensity fire, insect infestation, or disease kills individual trees within the stand reducing canopy cover to less than 20 percent. Over time young trees mature to replace and maintain the old-growth woodland. The mountain big sagebrush and perennial bunchgrass community increases in density and vigor. Annual non-natives present in trace amounts.
Pathway b
Community 2.4 to 2.2A high-severity crown fire will eliminate or reduce the singleleaf pinyon and Utah juniper overstory and the shrub component which will allow for the sprouting shrubs and perennial bunchgrasses to dominate the site. Annual non-native grasses typically respond positively to fire and may increase in the post-fire community.
State 3
Infilled Woodland StateThis state has two community phases that are characterized by the dominance of Utah juniper and singleleaf pinyon in the overstory. This state is identifiable by 30 to over 50 percent cover of Utah juniper and singleleaf pinyon. This stand exhibits a mixed age class. Older trees are at maximal height and upper crowns may be flat-topped or rounded. Younger trees are typically cone- or pyramidal-shaped. Understory vegetation is sparse due to increasing shade and competition from trees.
Community 3.1
Community PhaseSingleleaf pinyon and Utah juniper dominate the aspect. Understory vegetation is thinning. Perennial bunchgrasses are sparse and mountain big sagebrush skeletons are as common as live shrubs due to tree competition for soil water, overstory shading, and duff accumulation. Tree canopy cover is greater than 30 percent. Annual non-native species are present or co-dominate in the understory. Bare ground areas are prevalent and soil redistribution is evident.
Forest overstory.OVER-MATURE FORESTLAND: In the absence of wildfire or other naturally occurring disturbances, the tree canopy on this site can become very dense. This stage is dominated by singleleaf pinyon and Utah juniper that have reached maximal heights for the site. Dominant and co-dominant trees average greater than five inches in diameter at one-foot stump height. Upper crowns are typically irregularly flat-topped or rounded.
Forest understory. Understory vegetation is sparse or absent due to tree competition, overstory shading, duff accumulation, etc. Production ranges from 75 to 250 pounds per acre.
Community 3.2
Community PhaseSingleleaf pinyon and Utah juniper dominate the aspect. Tree canopy cover exceeds 30 percent and may be as high as 50 percent. Understory vegetation is sparse to absent. Perennial bunchgrasses, if present exist in the dripline or under the canopy of trees. Mountain sagebrush skeletons are common or the sagebrush has been extinct long enough that only scattered limbs remain. Mat-forming forbs or Sandberg’s bluegrass may dominate interspaces. Annual non-native species are present and are typically found under the trees. Bare ground areas are large and interconnected. Soil redistribution may be extensive. Tree recruitment is minimal. Trees are the dominant vegetation and are controlling ecological processes on the site.
Forest overstory.OVER-MATURE FORESTLAND: In the absence of wildfire or other naturally occurring disturbances, the tree canopy on this site can become very dense. This stage is dominated by singleleaf pinyon and Utah juniper that have reached maximal heights for the site. Dominant and co-dominant trees average greater than five inches in diameter at one-foot stump height. Upper crowns are typically irregularly flat-topped or rounded.
Forest understory. Understory vegetation is sparse or absent due to tree competition, overstory shading, duff accumulation, etc. Production ranges is less than 100 pounds per acre.
Pathway a
Community 3.1 to 3.2Time without disturbance such as fire, drought, or disease will allow for the gradual maturation of singleleaf pinyon and Utah juniper. Infilling by younger trees continues.
State 4
Annual StateThis community is characterized by the dominance of annual non-native species such as cheatgrass and mustards in the understory. Rabbitbrush may dominate the overstory. Annual non-native species dominate the understory.
Community 4.1
Community PhaseCheatgrass, mustards and other non-native annual species dominate the site. Trace amounts of perennial bunchgrasses may be present.
Transition A
State 1 to 2Trigger: Introduction of non-native annual species Slow variables: Over time the annual non-native plants will increase within the community. Threshold: Any amount of introduced non-native species causes an immediate decrease in the resilience of the site. Annual non-native species cannot be easily removed from the system and have the potential to significantly alter disturbance regimes from their historic range of variation.
Transition B
State 1 to 3Trigger: Time and a lack of disturbance allow trees to dominate site resources; may be coupled with inappropriate grazing management that favors shrub and tree dominance. Slow variables: Over time the abundance and size of trees will increase. Threshold: Juniper and pinyon canopy cover is greater than 30 percent. Little understory vegetation remains due to competition with trees for site resources.
Transition A
State 2 to 3Trigger: Time and a lack of disturbance allow trees to dominate site resources; may be coupled with inappropriate grazing management that favors shrub and tree dominance. Slow variables: Over time the abundance and size of trees will increase. Threshold: Juniper and pinyon canopy cover is greater than 30%. Little understory vegetation remains due to competition with trees for site resources.
Transition B
State 2 to 4Trigger: Catastrophic crown fire facilitates the establishment of non-native, annual weeds. Slow variables: Increase in tree crown cover, loss of perennial understory and an increase in annual non-native species. Threshold: Cheatgrass or other non-native annuals dominate understory. Loss of deep-rooted perennial bunchgrasses changes spatial and temporal nutrient cycling and nutrient redistribution, and reduces soil organic matter. Increased canopy cover of trees allows severe stand-replacing fire. The increased seed bank of non-native, annual species responds positively to post-fire conditions facilitating the transition to an Annual State.
Restoration pathway A
State 3 to 2Manual or mechanical thinning of trees coupled with seeding. Probability of success is highest from community phase 3.1.
Conservation practices
Brush Management Range Planting Transition A
State 3 to 4Trigger: Fire reduces the tree overstory and allows for the annual non-native species in the understory to dominate the site. Soil disturbing treatments such as slash and burn may also reduce tree canopy and allow for non-native annual species to increase. Slow variables: Over time, cover and production of annual non-native species increases. Threshold: Loss of deep-rooted perennial bunchgrasses and shrubs changes temporal and spatial nutrient capture and cycling within the community. Increased, continuous fine fuels modify the fire regime by increasing frequency, size, and spatial variability of fires.
Additional community tables
Table 6. Community 1.1 plant community composition
Group Common name Symbol Scientific name Annual production () Foliar cover (%) Grass/Grasslike1 Primary Perennial Grasses 125–255 bluebunch wheatgrass PSSPS Pseudoroegneria spicata ssp. spicata 50–120 – Indian ricegrass ACHY Achnatherum hymenoides 25–45 – basin wildrye LECI4 Leymus cinereus 25–45 – muttongrass POFE Poa fendleriana 25–45 – 2 Secondary Perennial Grasses 11–55 squirreltail ELEL5 Elymus elymoides 5–25 – Sandberg bluegrass POSE Poa secunda 5–25 – blue grama BOGR2 Bouteloua gracilis 1–5 – Forb3 Perennial Forbs 30–70 buckwheat ERIOG Eriogonum 5–25 – phlox PHLOX Phlox 1–5 – rockcress ARABI Arabidopsis 1–5 – Shrub/Vine4 Primary Shrubs 175–340 mountain big sagebrush ARTRV Artemisia tridentata ssp. vaseyana 125–250 – curl-leaf mountain mahogany CELE3 Cercocarpus ledifolius 25–45 – antelope bitterbrush PUTR2 Purshia tridentata 25–45 – 5 Secondary Shrubs 10–50 Utah serviceberry AMUT Amelanchier utahensis 5–25 – snowberry SYMPH Symphoricarpos 5–25 – Tree6 Trees 10–50 Utah juniper JUOS Juniperus osteosperma 5–25 – singleleaf pinyon PIMO Pinus monophylla 5–25 – Table 7. Community 1.2 plant community composition
Group Common name Symbol Scientific name Annual production () Foliar cover (%) Table 8. Community 1.3 plant community composition
Group Common name Symbol Scientific name Annual production () Foliar cover (%) Table 9. Community 1.4 plant community composition
Group Common name Symbol Scientific name Annual production () Foliar cover (%) Table 10. Community 2.1 plant community composition
Group Common name Symbol Scientific name Annual production () Foliar cover (%) Table 11. Community 2.2 plant community composition
Group Common name Symbol Scientific name Annual production () Foliar cover (%) Table 12. Community 2.3 plant community composition
Group Common name Symbol Scientific name Annual production () Foliar cover (%) Table 13. Community 2.4 plant community composition
Group Common name Symbol Scientific name Annual production () Foliar cover (%) Table 14. Community 3.1 plant community composition
Group Common name Symbol Scientific name Annual production () Foliar cover (%) Table 15. Community 3.2 plant community composition
Group Common name Symbol Scientific name Annual production () Foliar cover (%) Table 16. Community 4.1 plant community composition
Group Common name Symbol Scientific name Annual production () Foliar cover (%) Interpretations
Animal community
Livestock Interpretations:
The history of livestock grazing in the pinyon-juniper ecosystem goes back to more than 200 years, depending on the particular locality within the ecosystem (Hurst 1975). Historically, pinyon-juniper woodlands were much more open and supported a diverse understory that provided forage for both livestock and wildlife. Historic livestock overuse and increased stand densities have reduced the carrying capacity of these pinyon-juniper stands and many current stands only provide shade and shelter for livestock.
Inappropriate grazing management during the growing season will cause a decline in understory plants such as bluebunch wheatgrass, Indian rice ricegrass and Thurber’s needlegrass. Bluebunch wheatgrass is moderately grazing tolerant and is very sensitive to defoliation during the active growth period (Blaisdell and Pechanec 1949, Laycock 1967, Anderson and Scherzinger 1975, Britton et al. 1990). Herbage and flower stalk production was reduced with clipping at all times during the growing season; however, clipping was most harmful during the boot stage (Blaisdell and Pechanec 1949). Tiller production and growth of bluebunch was greatly reduced when clipping was coupled with drought (Busso and Richards 1995). Mueggler (1975) estimated that low vigor bluebunch wheatgrass may need up to 8 years rest to recover. Although an important forage species, it is not always the preferred species by livestock and wildlife.
Thurber’s needlegrass is an important forage source for livestock and wildlife in the arid regions of the West (Ganskopp 1988). Although the seeds are apparently not injurious, grazing animals avoid them when they begin to mature. Sheep, however, have been observed to graze the leaves closely, leaving stems untouched (Eckert and Spencer 1987). Heavy grazing during the growing season has been shown to reduce the basal area of Thurber’s needlegrass (Eckert and Spencer 1987), suggesting that both seasonality and utilization are important factors in management of this plant. A single defoliation, particularly during the boot stage, was found to reduce herbage production and root mass thus potentially lowering the competitive ability of this needlegrass (Ganskopp 1988).
Indian ricegrass is a preferred forage species for livestock and wildlife (Cook 1962, Booth et al. 2006). This species is often heavily utilized in winter because it cures well (Booth et al. 2006). It is also readily utilized in early spring, being a source of green feed before most other perennial grasses have produced new growth (Quinones 1981). Booth et al. (2006) note that the plant does well when utilized in winter and spring. Cook and Child (1971) however, found that repeated heavy grazing reduced crown cover, which may reduce seed production, density, and basal area of these plants. Additionally, heavy early spring grazing reduces plant vigor and stand density (Stubbendieck 1985). In eastern Idaho, productivity of Indian ricegrass was at least 10 times greater in undisturbed plots than in heavily grazed ones (Pearson 1965). Cook and Child (1971) found significant reduction in plant cover after 7 years of rest from heavy (90%) and moderate (60%) spring use. The seed crop may be reduced where grazing is heavy (Bich et al. 1995). Tolerance to grazing increases after May, thus spring deferment may be necessary for stand enhancement (Pearson 1964, Cook and Child 1971); however, utilization of less than 60% is recommended.
Reduced bunchgrass vigor or density provides an opportunity for Sandberg bluegrass, mat forming forbs and/or cheatgrass and other invasive species to occupy interspaces. Sandberg bluegrass increases under grazing pressure (Tisdale and Hironaka 1981) and is capable of co-existing with cheatgrass. Excessive sheep grazing favors Sandberg bluegrass; however, where cattle are the dominant grazers, cheatgrass often dominates (Daubenmire 1970). Thus, depending on the season of use, the grazer and site conditions, either Sandberg bluegrass or cheatgrass may become the dominant understory with inappropriate grazing management. Field surveys indicate native, mat-forming forbs may also increase with decreased bunchgrass density.
Wildlife Interpretations:
Pinyon-juniper woodlands provide a diversity of habitat for wildlife. Although the foliage of pinyon and juniper varies in palatability among fauna, the pinyon nuts and juniper berries are preferred by many species. The understory species provide fruits and browse for large ungulates, small mammals, birds and beaver (Wildlife Action Plan Team 2012).
Ungulates will use pinyon and juniper trees for cover and graze the foliage. The understory species also provide critical browse for deer. The trees provide important cover for mule deer (Odocoileus heminous), elk (Cervus canadensis) wild horses, mountain lion (Puma concolor), bobcat (Lynx rufus) and pronghorn (Antilocapra americana) (Gottfried and Severson 1994, Coates and Schemnitz 1994, Logan and Irwin 1985, Evans 1988).
Mule deer is considered the dominant big game species in the pinyon-juniper woodland and depend heavily on these woodlands for cover, shelter, and emergency forage during severe winters (Frischknecht 1975). Mule deer will eat singleleaf pinyon and juniper foliage, using the foliage moderately in winter, spring, and summer (Kufeld et al. 1973). Deep snows in higher elevation forest zones force mule deer and elk down into pinyon-juniper habitats during winter. This change in habitat allows mule deer and elk to browse the dwarf trees and shrubs (Gottfried and Severson 1994).
The diet of pronghorn antelope varies considerably; however, singleleaf pinyon was shown to comprise 1 to 2 percent of winter diet of pronghorn antelope that occur in pinyon-juniper habitat. Desert bighorn sheep (Ovis nelson) may utilize pinyon-juniper habitat, but only where the terrain is rocky and steep (Gottfried et al. 2000). Gray foxes, bobcats (Lynx rufus), coyotes (Canis latrans), weasels (Mustela frenata), skunks (Mephitis spp.), badgers (Taxidea taxus), and ringtail cats (Bassariscus astutus) search for prey in pinyon-juniper habitat woodlands (Short and McCulloch 1977).
Juniper "berries" or berry-cones are eaten by black-tailed jackrabbits, Lepus californicus, and coyotes (Gese et al. 1988, Kitchen et al. 2000). A study by Kitchen et al (1999) conducted in juniper-pinion habitat found vegetation in coyote scats was mainly grass seeds or juniper berries. Jackrabbits are a major dispenser of juniper seeds (Schupp et al. 1999). The pinyon mouse (Peromyscus truei) is a pinyon-juniper obligate and uses the woodlands for cover and food (Hoffmeister 1981). Other small mammals include the porcupine (Hystricomorph hystricidae), desert cottontail (Sylvilagus audubonii), Nuttall’s cottontail (S. nuttallii), deer mouse (Peromyscus maniculatus), Great Basin pocket mouse (Perognathus parvus), chisel-toothed kangaroo rat (Dipodomys microps) and desert woodrat (Neotoma lepida) (Turkowski and Watkins 1976).
Many bird species are associated with the pinyon-juniper habitat; some are permanent residents, some summer residents, and some winter residents, depending upon location. For birds and bats, the woodland provides structure for nesting and roosting, and locations for foraging. Singleleaf pinyon provides a number of cavities and the stringy, fibrous bark provides quality nesting material as well as the food provided by the tree’s seeds and berries (Short and McCulloch 1977). Many bird species depend on juniper berry-cones and pine nuts for fall and winter food (Balda and Masters 1980). Several bird species are obligates including (gray flycatcher (Epidonax wrightii) scrub jay (Aphelocoma californica), plain titmouse (Parus inornatus ridgwayi), and gray vireo (Vireo vicinior) and several species are semi-obligates including black-chinned hummingbird (Archilochus alexandri), ash-throated flycatcher (Myiarchus cinerascens), pinion jay (Gymnorhinus cyanocephalus), American bushtit (Psaltriparus minimus), Bewick’s wren (Thryomanes bewickii), Northern mockingbird (Mimus polyglottos), blue-gray gnatcatcher (Polioptila caerulea), black-throated gray warbler (Dendroica nigrescens), house finch (Haemorhous mexicanus), spotted towhee (Pipilo maculatus), lark sparrow (Chondestes grammacus) and black-chinned sparrow (Zonotrichia atricapilla) (Balda and Masters 1980). Ferruginous hawk (Buteo regalis), a conservation priority species due to recent population declines in Nevada, nest in older trees of sufficient size and structure to support their large nest platforms. (Holechek 1981).
Diurnal reptiles include the sagebrush swift (Sceloporus graciosus), the blue-bellied lizard (Sceloporus elongates) the western collard lizard, the Great Basin rattlesnake, the Great Basin gopher snake (Pituophis catenifer) and horned lizard, also occur in Utah juniper habitat (Frischknecht 1975). However, the distribution of most of herpetofauna present in pinyon-juniper woodlands is poorly understood and more research and management are needed.
Hydrological functions
Runoff is medium to very high. Permeability is moderate to moderately slow. Hydrologic soil group is D. Hydrologic processes are influenced by species composition, structural development and density patterns of the tree overstories and the nature of precipitation events occurring. Interception of precipitation is related to the composition, distribution, and density of trees in the overstory and intensity, duration, and type of precipitation. Infiltration rates are typically greater beneath tree overstories than on sites supporting herbaceous plants because the trees reduce the raindrop impact. The litter accumulation beneath the trees also slows overland flows. Evapotranspiration is generally the largest route of water outflow from the site (Ffolliott and Gottfried 2012).
Recreational uses
The trees on this site provide a welcome break in an otherwise open landscape. It has potential for hiking, cross-country skiing, camping, and deer and upland game hunting.
Wood products
PRODUCTIVE CAPACITY
This forest community is of moderately low site quality for tree production. Site index ranges from 35 to 55 (Howell, 1940).
Productivity Class: 0.2 to 0.4
CMAI*: 2.7 to 5.2 ft3/ac/yr;
0.19 to 0.36 m3/ha/yr.
Culmination is estimated to be at 90 years.
*CMAI: is the culmination of mean annual increment or highest average growth rate of the stand in the units specified.
Fuelwood Production: 7 to 10 cords per acre for stands averaging 5 inches in diameter at 1 foot height with a medium canopy cover. There are about 289,000 gross British Thermal Units (BTUs) heat content per cubic foot of pinyon pine wood and about 274,000 gross BTUs heat content per cubic foot of Utah juniper. Solid wood volume in a cord varies but usually ranges from 65 to 90 cubic feet. Assuming an average of 75 cubic feet of solid wood per cord, there are about 21 million BTUs of heat value in a cord of mixed pinyon pine and Utah juniper.
Posts (7 foot): About 25 to 50 posts per acre in stands of medium canopy.
Christmas trees: 15 trees per acre per year in stands of medium canopy. Over thirty trees per acre in stands of sapling stage.
Pinyon nuts: Production varies year to year, but mature forestland stage can yield 150 to 250 pounds per acre in favorable years.
B. MANAGEMENT GUIDES AND INTERPRETATIONS
1. LIMITATIONS AND CONSIDERATIONS
a. Potential for sheet and rill erosion is moderate to severe depending on slope.
b. Moderate to severe equipment limitations on steeper slopes and moderate to severe equipment limitations on sites having extreme surface stoniness.
c. Proper spacing is the key to a well managed, multiple use and multi-product pinyon-juniper forestland.
2. ESSENTIAL REQUIREMENTS
a. Adequately protect from wildfire.
b. Protect soils from accelerated erosion.
c. Apply proper grazing management.
3. SILVICULTURAL PRACTICES
a. Harvest cut selectively or in small patches size dependent upon site conditions) to enhance forage production.
1) Thinning and improvement cutting - Removal of poorly formed, diseased and low vigor trees for fuelwood.
2) Harvest cutting - Selectively harvest surplus trees to achieve desired spacing. Save large, healthy, full-crowned singleleaf pinyon trees for nut producers. Do not select only "high grade" trees during harvest.
3) Slash Disposal - broadcasting slash improves reestablishment of native understory herbaceous species and establishment of seeded grasses and forbs after tree harvest.
4) Spacing Guide - D+10 to D+12
a. Prescription burning program to maintain desired canopy cover and manage site reproduction.
b. Mechanical tree removal (i.e. chaining) is usually not recommended on this site due to steep slopes.
c. Pest control - Porcupines can cause extensive damage and populations should be controlled.
d. Fire hazard - Fire usually not a problem in well-managed, mature stands.Other products
Pinyon wood is rather soft, brittle, heavy with pitch, and yellowish brown in color. Singleleaf pinyon has played an important role as a source of fuelwood and mine props. It has been a source of wood for charcoal used in ore smelting. It still has a promising potential for charcoal production. Other important uses for this tree are for Christmas trees and as a source of nuts for wildlife and human food. These trees have provided Indians with food for centuries. Thousands of pounds of nuts are gathered each year and sold on commercial markets throughout the United States. Utah juniper wood is very durable. Its primary uses have been for posts and fuelwood. It probably has considerable potential in the charcoal industry and in wood fiber products. The berries have been used by Indians for food. Native Americans used big sagebrush leaves and branches for medicinal teas, and the leaves as a fumigant. Bark was woven into mats, bags and clothing. Indian ricegrass was traditionally eaten by some Native Americans. The Paiutes used seed as a reserve food source. Basin wildrye was used as bedding for various Native American ceremonies, providing a cool place for dancers to stand. The pitch of singleleaf pinyon was used by Native Americans as an adhesive, caulking material, and a paint binder. It may also be used medicinally and chewed like gum. Pinyon seeds are a valuable food source for humans, and a valuable commercial crop.
Other information
Antelope bitterbrush has been used extensively in land reclamation. Antelope bitterbrush enhances succession by retaining soil and depositing organic material and in some habitats and with some ecotypes, by fixing nitrogen. Curlleaf mountainmahogany may be planted to help stabilize soil in disturbed areas such as roadcuts and mine spoils. Basin wildrye is useful in mine reclamation, fire rehabilitation and stabilizing disturbed areas. Its usefulness in range seeding, however, may be limited by initially weak stand establishment.
Table 17. Representative site productivity
Common name Symbol Site index low Site index high CMAI low CMAI high Age of CMAI Site index curve code Site index curve basis Citation singleleaf pinyon PIMO 35 55 3 5 90 200 N/A Howell, Joseph Jr. 1940. Pinon [sic] and juniper, a preliminary study of volume, growth and yield. USDA, Soil Conservation Service. Region 8 Regional Bulletin 71, Forest Series 12. Supporting information
Type locality
Location 1: White Pine County, NV Township/Range/Section T18N R68E S34 UTM zone N UTM northing 4362659 UTM easting 731641 Latitude 39° 22′ 56″ Longitude 114° 18′ 38″ General legal description SE¼ Section 34, T18N. R68E. MDBM. About 3½ miles east of Eight Mile Ranch, Snake Range, White Pine County, Nevada. This site also occurs in Lincoln County, Nevada. Location 2: Lincoln County, NV Township/Range/Section T4N R65E S11 Latitude 38° 13′ 35″ Longitude 114° 39′ 17″ General legal description About 22 miles northwest of Pioche in the Fairview Range. Lincoln County, Nevada Other references
Anderson, E. W. and R. J. Scherzinger. 1975. Improving quality of winter forage for elk by cattle grazing.Journal of Range Management 28:120-125.
Baker, W.L. and D.J. Shinneman, 2004. Fire and restoration of pinon-juniper woodlands in the western United States. A review. Forest Ecology and Management 189:1-21.
Balda, R. P. and N. Masters. 1980. Avian communities in the pinyon-juniper woodland: a descriptive analysis. In: DeGraaf, R. M., technical coordinator. Management of Western Forests and Grasslands for Nongame Birds: Workshop proceedings. 1980 February 11-14; Salt Lake City, UT. Gen. Tech. Rep. INT-86.
Ogden, UT: U.S. Department of Agriculture, Forest Service, Intermountain Forest and Range Experiment Station. p. 146-169.
Beardall, L. E. and V. E. Sylvester. 1976. Spring burning of removal of sagebrush competition in Nevada.
Pages 539-547 In: Proceedings- Tall Timbers fire ecology conference and fire and land management symposium. Tall Timbers Research Station.
Bich, B. S., J. L. Butler, and C. A. Schmidt. 1995. Effects of differential livestock use on key plant species and rodent populations within selected Oryzopsis hymenoides/Hilaria jamesii communities of Glen Canyon National Recreation Area. The Southwestern Naturalist 40:281-287.
Blaisdell, J. P. 1953. Ecological effects of planned burning of sagebrush-grass range on the upper Snake River Plains. Technical bulletin 1075. US Department of Agriculture. p. 39
Blaisdell, J. P. and J. F. Pechanec. 1949. Effects of herbage removal at various dates on vigor of bluebunch wheatgrass and arrowleaf balsamroot. Ecology 30: 298-305.
Blaisdell, J. P., R. B. Murray, and E. D. McArthur. 1982. Managing intermountain rangelands-sagebrush- grass ranges. Gen. Tech. Rep. INT-134. U.S. Department of Agriculture, Forest Service, Intermountain Forest and Range Experiment Station, Ogden, UT. p. 41
Booth, D. T., C. G. Howard, and C. E. Mowry. 2006. 'Nezpar' Indian ricegrass: description, justification for release, and recommendations for use. Rangelands Archives 2:53-54.
Bradley, A. F., N. V. Noste, and W. C. Fischer. 1992. Gen. Tech. Rep. INT-287: Fire Ecology of Forests and Woodlands in Utah. U.S. Department of Agriculture, Forest Service, Intermountain Research Station, Ogden, UT. p. 128
Britton, C. M., G. R. McPherson, and F. A. Sneva. 1990. Effects of burning and clipping on five bunchgrasses in eastern Oregon. Great Basin Naturalist 50:115-120.
Bunting, S. 1994. Effects of Fire on Juniper woodland ecosystems in the great basin. In: Monsen, S.B. and
S.G. Kitchen (compilers). Proceedings--ecology and management of annual rangelands, 18-22 May 1992, Boise, ID. Ogden, UT: U.S. Department of Agriculture, Forest Service, Intermountain Research Station. Gen. Tech. Rep. INT-GTR-313.
Bunting, S. C., B. M. Kilgore, and C. L. Bushey. 1987. Guidelines for prescribed burning sagebrush-grass rangelands in the northern Great Basin. Gen. Tech. Rep. INT-231. US Department of Agriculture, Forest Service, Intermountain Research Station Ogden, UT, USA. p. 33
Burkhardt, J. W. and E. W. Tisdale. 1969. Nature and successional status of Western Juniper vegetation in Idaho. Journal of Range Management 22:264-270.
Busso, C. A. and J. H. Richards. 1995. Drought and clipping effects on tiller demography andgrowth of two tussock grasses in Utah. Journal of Arid Environments 29:239-251.
Caudle, D., J. DiBenedetto, M. Karl, H. Sanchez, and C. Talbot. 2013. Interagency Ecological Site Handbook for Rangelands. Available at: http://jornada.nmsu.edu/sites/jornada.nmsu.edu/files/InteragencyEcolSiteHandbook.pdf. Accessed 4 October 2013.
Chambers, J., B. Bradley, C. Brown, C. D’Antonio, M. Germino, J. Grace, S. Hardegree, R. Miller, and D. Pyke. 2013. Resilience to stress and disturbance, and resistance to Bromus tectorum L. invasion in cold desert shrublands of western North America. Ecosystems :1-16.
Chambers, J.C., E.W. Schupp and S.B. Vander Wall. 1999. Seed dispersal and seedling establishment of pinyon and juniper species within the pinon-juniper woodland. In: Proceedings: Ecology and Management of Pinyon–Juniper Communities Within the Interior West. Ogden, UT, USA: US Department of Agriculture, Forest Service, Rocky Mountain Research Station, RMRS-P-9. p. 29- 34.
Christopherson, J. 2014. Dwarf Mistletoe (Arceuthobium spp.). Nevada Division of Forestry, 2478 Fairview Drive Carson City, Nevada 89701.
Coates, K.P. and S.D. Schemnitz. 1994. Habitat use and behavior of male mountain sheep in foraging associations with wild horses. Great Basin Naturalist. 54:86-90
Conrad, C. E. and C. E. Poulton. 1966. Effect of a wildfire on Idaho fescue and bluebunch wheatgrass. Journal of Range Management 19:138-141.
Daubenmire, R. 1970. Steppe Vegetation of Washington. 131 pp.
Daubenmire, R. 1975. Plant succession on abandoned fields, and fire influences in a steppe area in southeastern Washington. Northwest Science 49:36-48.
Durham, G. 2014. Juniper Pocket Rot (Pyrofomes demidoffii.). Nevada Division of Forestry, 2478 Fairview Drive, Carson City, Nevada 89701.
Eckert, R. E., Jr. and J. S. Spencer. 1987. Growth and reproduction of grasses heavily grazed under rest- rotation management. Journal of Range Management 40:156-159.
Eddleman, L.E., P.M. Miller, R.F. Miller, P.L. Dysart. 1994. Western juniper woodlands of the pacific northwest: science assessment. Department of Rangeland Resources, Oregon State University, Corvallis, OR.
Emerson, F.W. 1932. The tension zone between the grama grass and pinyon-juniper associations in northeastern New Mexico. Ecology: 13: 347-358.
Evans, Raymond A. 1988. Management of pinyon-juniper woodlands. Gen. Tech. Rep. INT-249. Ogden, UT: U.S. Department of Agriculture, Forest Service, Intermountain Research Station. 34 pp.
Evans, R. A. and J. A. Young. 1978. Effectiveness of rehabilitation practices following wildfire in a degraded big sagebrush-downy brome community. Journal of Range Management 31:185-188.
Everett, R. L. and K. Ward. 1984. Early plant succession on pinyon-juniper controlled burns. Northwest Science 58:57-68.
Fire Effects Information System (Online; http://www.fs.fed.us/database/feis/plants/).
Ffolliott, P.F. and G.J. Gottfried. 2012. Hydrologic processes in the pinyon-juniper woodlands: A literature review. Gen. Tech. Rep. RMRS-GTR-271. Fort Collins, CO. U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station. 20 p.
Frischknecht, N.C. 1975. Native faunal relationships within the pinyon-juniper ecosystem. Pp. 55-65. In: Proceedings of The Pinyon-Juniper Ecosystem: A Symposium. May 1975. Utah State University. Logan, UT.
Furniss, M. M. and W. F. Barr. 1975. Insects affecting important native shrubs of the northwestern United States. US Intermountain Forest And Range Experiment Station. General Technical Report INT-19. U.S. Department of Agriculture, Forest Service, Intermountain Forest and Range Experiment Station. Ogden UT. p. 64.
Ganskopp, D. 1988. Defoliation of Thurber needlegrass: herbage and root responses. Journal of Range Management 41:472-476.
Gese, E.M., O.J. Rongstad and W.R. Mytton 1988. Home range and habitat use of coyotes in southeastern Colorado. Journal of Wildlife Management 52:640-646.
Gottfried, G.J. and K.E. Severson. 1994. Managing pinyon-juniper woodlands. Rangelands 16:234-236 Gottfried, G.J.; Folliott, P.F.; Baker, M.B., Jr. 2000. Measurement of historical inventory locations to
assess changes in forest and woodlands in Arizona. In: Cook, J.E.; Oswald, B.P. (comp). First Biennial North American Forest Ecology Workshop. June 24-26, 1997; North Carolina State University, Raleigh, NC. 51-52 p.
Gruell, G.E. 1999. Historical and modern roles of fire in pinyon-juniper. In: S. B. Monsen, R. Stevens [comps.] Proceedings: ecology and management of pinyon–juniper communities within the Interior West. RMRS-P-9. Ogden, UT, USA: US Department of Agriculture, Forest Service, Rocky Mountain Research Station. p. 24-28.
Hepting, G.H. 1971. Diseases of Forest and Shade Trees of the United States. U.S. Department of Agriculture Handbook 386. 658 pp.
Heyerdahl, E.K., Miller, R.F, and Parsons, R.A. 2006. History of fire and Douglas-fir establishment in a savanna and sagebrush grassland mosaic, southwestern Montana, USA. Forest Ecology and Management. 230:107-118.
Hironaka, M., M. A. Fosberg, and A. H. Winward. 1983. Sagebrush-grass habitat types of southern Idaho.
Bulletin Number 35. University of Idaho, Forest, Wildlife and Range Experiment Station, Moscow, ID.
Hoffmeister, D.F. 1981. Mammalian species: Peromyscus truei. The American Society of Mammologists 161:1-5.
Holechek, J. L. 1981. Brush control impacts on rangeland wildlife. Journal of Soil and Water Conservation 36: 265-269.
Holmes, R.L., R.K., Adams, H.C. Fritts. 1986. Tree ring chronologies of western North America: California, eastern Oregon and northern Great Basin. Chronology Series VI. Laboratory of Tree Ring Research, University of Arizona, Tucson, AZ 183 pp.
Houghton, J.G., C.M. Sakamoto, and R.O. Gifford. 1975. Nevada’s Weather and Climate, Special Publication 2. Nevada Bureau of Mines and Geology, Mackay School of Mines, University of Nevada, Reno, NV.
Howell, J., 1940. Pinyon and juniper: a preliminary study of volume, growth, and yield. Regional Bulletin 71. Albuquerque, NM: USDA, SCS; 90p.
Houston, D. B. 1973. Wildfires in northern Yellowstone National Park. Ecology 54:1111-1117.
Huber, A., S. Goodrich, K. Anderson. 1999. Diversity with successional status in the pinyon-juniper/mountain mahogany/bluebunch wheatgrass community type near Dutch John, Utah. In: S. B. Monsen, R. Stevens [comps.] Proceedings ecology and management of pinyon-juniper communities within the Interior West; 1997 September 15-18. RMRS-P-9. US Department of Agriculture, Forest Service, Rocky Mountain Research Station Proceedings. p. 114-117.
Hurst, W.D. 1975. Management strategies within the pinyon-juniper ecosystem. Pp. 187-192.
Proceedings of The Pinyon-Juniper Ecosystem: A Symposium. Utah State University, Logan, UT.
Jameson, D.A. 1970. Degradation and accumulation on inhibitory substances from Juniperus osteosperma (Torr.) Little. Plant Soil 33: 213-224.
Kitchen, A.M., E.M. Gese, and E.R. Schauster. 2000. Changes in coyote activity patterns due to reduced exposure to human persecution. Canada Journal of Zoology. 78:853-857.
Koniak, S. 1985. Succession in pinyon-juniper woodlands following wildfire in the Great Basin. The Great Basin Naturalist 45:556-566.
Kufeld, R.C., O.C. Wallmo and C. Feddema. 1973. Foods of the Rocky Mountain Mule Deer. Rocky Mountain Forest and Range Experiment Station. USDA Forest Service, Research Paper RM-111. P. 31.
Lanner, R.M. 1981. The Pinon Pine – A Natural and Cultural history. University of Nevada Press, Reno, NV.
Laycock, W. A. 1967. How heavy grazing and protection affect sagebrush-grass ranges. Journal of Range Management 20:206-213.
Ligon, J. D. 1974. Green cones of the pinon pine stimulate late breeding in the pinon jay. Nature 250 (5461): 80-82.
Logan, K. A., Irwin, L. L. 1985. Mountain lion habitats in the Big Horn Mountains, Wyoming. Wildlife Society Bulletin 13: 257-262.
McArthur, E. D., A. Blaner, A. P. Plummer, and R. Stevens. 1982. Characteristics and hybridization of important Intermountain shrubs: 3. Sunflower family. En Ref. in Forest. Abstr 43:2176.
Meewig, R.O. and R.L. Bassett. 1983. Pinyon-juniper. In: R. Burns [comp.] Silvicultural Systems for the Major Forest Types of the United States. Pp. 84-86. Agric. Handbook. 455, Washington, D.C., USA.
Miller, R.F. and T.J. Rose. 1995. Historic expansion of Juniperus occidentalis (western juniper) in southeastern Oregon. Great Basin Naturalist. 55:37-45.
Miller, R.F. and T.J. Rose. 1999. Fire history and western juniper encroachment in sagebrush steppe. Journal of Range Management.52:550-559.
Miller, R.F. R.J. Tausch and W. Waichler. 1999. Old-growth juniper and pinyon woodlands. In: Monsen,S.D. and R. Stevens. Comps. Proceedings: Ecology and Management of Pinyon-Juniper communities within the interior West; 1997 September 15-18; Provo, UT. USDA, Forest Service RMRS-P-9: 375-384 Logan Ut.
Miller, R.F. and R.J. Tausch. 2001. The role of fire in pinyon and juniper woodlands: a descriptive analysis. In: Galley, K.E.M., Wilson, T.P. eds. Invasive Species: the role of fire in the control and spread of invasive species symposium. Miscellaneous Publication No. 11, Tall Timbers Research Station, Tallahassee, FL. 15-30.
Miller, R. F. and E. K. Heyerdahl. 2008. Fine-scale variation of historical fire regimes in sagebrush-steppe and juniper woodland: an example from California, USA. International Journal of Wildland Fire 17:245-254.
Miller, R.F. R.J. Tasuch, E.D. McArthur, D.D. Johnson and S.C. Sanderson. 2008. Age Structure and Expansion of Pinon-Juniper Woodlands: A Regional Perspective in the Intermountain West. Res. Pap. RMRS-RP-69. Fort Collins CO: U.S. Department of Agriulture, Forest Service, Rocky Mountain Research Station. p. 15.
Mueggler, W. F. 1975. Rate and pattern of vigor recovery in Idaho fescue and bluebunch wheatgrass. Journal of Range Management 28:198-204.
National Oceanic and Atmospheric Administration. 2004. The North American Monsoon. Reports to the Nation. National Weather Service, Climate Prediction Center. Available online: http://www.weather.gov/
Neuenschwander, L. 1980. Broadcast burning of sagebrush in the winter. Journal of Range Management 33:233-236.
Noy-Meir, I. 1973. Desert Ecosystems: Environment and Producers. Annual Review of Ecology and Systematics 4:25-51.
Pearson, L. 1964. Effect of harvest date on recovery of range grasses and shrubs. Agronomy Journal 56:80-82.
Pearson, L. C. 1965. Primary Production in Grazed and Ungrazed Desert Communities of Eastern Idaho. Ecology 46:278-285.
Phillips, F. J. 1909. A study of pinyon pine. Bot. Gaz. 48: 216-223.
Phillips, G. 2014. Pinyon Needle Scales. Nevada Divison of Forestry, 2478 Fairview Drive, Carson City, Nevada.
Quinones, F. A. 1981. Indian ricegrass evaluation and breeding. Bulletin 681. Page 19. New Mexico State University, Agricultural Experiment Station, Las Cruces, NM.
Robberecht, R. and G. Defossé. 1995. The relative sensitivity of two bunchgrass species to fire. International Journal of Wildland Fire 5:127-134.
Romme, W., C.Allen, J. Bailey, W.Baker, B. Bestelmeyer, P. Brown, K. Eisenhart, L. Floyd-Hanna, D. Huffman, B.Jacobs, R. Miller, E. Muldavin, T. Swetnam, R. Tausch, and P. Weisberg. 2007. Historical and Modern Disturbance Regimes of Pinon-Juniper Vegetation in the Western U.S. 13pp.
Schupp, E.W., J.C. Chambers, S.B. Vander Wall, J.M. Gomez, M. Fuentes. 1999. Piñon and juniper seed dispersal and seedling recruitment at woodland ecotones. In: E. D. McArthur, K. W. Ostler, L. Carl [comps.] Proceedings: Shrubland ecotones; 1998 August 12-14; Ephraim UT. Proc. RMRS-P-
11. Ogden UT: U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station. p. 66-70
Sheehy, D. P. and A. H. Winward. 1981. Relative palatability of seven Artemisia taxa to mule deer and sheep. Journal of Range Management 34:397-399.
Short, H.L. and C.Y. McCulloch. 1977. Managing Pinyon-Juniper Ranges for Wildlife. USDA For. Ser. Gen Tech Rept. RM-47. Rocky Mountain Forest and Range Experiment Station, Fort Collins, CO. 10 pp.
Stringham, T.K., P. Novak-Echenique, P. Blackburn, C. Coombs, D. Snyder and A. Wartgow. 2015. Final Report for USDA Ecological Site Description State-and-Transition Models, Major Land Resource Area 28A and 28B Nevada. University of Nevada Reno, Nevada Agricultural Experiment Station Research Report 2015-01. p. 1524.
Tausch, R. J. 1999. Historic pinyon and juniper woodland development. In: S. B. Monsen, R. Stevens [comps.] Proceedings ecology and management of pinyon-juniper communities within the Interior West; 1997 September 15-18. RMRS-P-9. US Department of Agriculture, Forest Service, Rocky Mountain Research Station Proceedings. p. 12-19.
Tausch, R. J. and N. E. West. 1988. Differential establishment of pinyon and juniper following fire. American Midland Naturalist 119:174-184.
Tausch, R.J., N.E. West, and A.A. Nabi. 1981. Tree age and dominance patterns in Great Basin pinyon- juniper woodlands. Journal of Range Management 34: 259-264.
Tisdale, E. W. and M. Hironaka. 1981. The sagebrush-grass region: A review of the ecological literature. University of Idaho, Forest, Wildlife and Range Experiment Station.
Tueller, P.T., and J.E. Clark. 1975. Autecology of pinyon-juniper species of the Great Basin and Colorado Plateau. Pp. 27-40. Proceedings of The Pinyon-Juniper Ecosystem: A Symposium. Utah State University, Logan, UT.
Turkowski, F. J. and R. K. Watkins. 1976. White-throated woodrat (Neotoma albigula) habitat relations in modified pinyon-juniper woodland of southwestern New Mexico. Journal of Mammalogy. 57: 586-591.
Uresk, D. W., J. F. Cline, and W. H. Rickard. 1976. Impact of wildfire on three perennial grasses in south- central Washington. Journal of Range Management 29:309-310.
USDA-NRCS Plants Database (Online; http://www.plants.usda.gov).
USDA-NRCS. National Forestry Manual - Part 537. Washington, D.C.
Vallentine, J. F. 1989. Range Development and Improvements. Academic Press, Inc. San Diego, CA. p.524.
Vose, J. M. and A. S. White. 1991. Biomass response mechanisms of understory species the first year after prescribed burning in an Arizona ponderosa-pine community. Forest Ecology and Management 40:175-187.
Weisberg, P.J. and W.K. Dongwook. 2012. Old tree morphology in singleleaf pinyon pine (Pinus monophylla). Forest Ecology and Management 263:67-73.
West, N. E. 1994. Effects of fire on salt-desert shrub rangelands. In: S. B. Monsen [ed.] Proceedings-- Ecology and Management of Annual Rangelands, General Technical Report INT-313. U.S. Department of Agriculture, Forest Service, Intermountain Research Station, Boise, ID. p. 71-74.
West, N.E., K.H. Rea, and R.J. Tausch. 1975. Basic synecological relationships in juniper-pinyon woodlands. Pp 41-52. Proceedings of The Pinyon-Juniper Ecosystem: A Symposium. Utah State University, Logan, UT.
West, N.E. R.J. Tausch and P.T. Tueller. 1998. A Management Oriented Classificaton of Pinyon-juniper Woodlands in the Great Basin. Gen. Tech. Rep. RMRS-GTR-12. Ogden, UT: U.S. Department of Agriculture, Forest Service, Rocky Mountain Research Station. p. 42.
Wildlife Action Plan Team. 2012. Nevada Wildlife Action Plan. Nevada Department of Wildlife, Reno, NV.
Wright, H. A. 1985. Effects of fire on grasses and forbs in sagebrush-grass communities. Pages 12-21 in: K. Sanders, J. Durham [eds.] Rangeland Fire Effects; A Symposium: Boise, ID, USDI-BLM.
Wright, H. A. and J. O. Klemmedson. 1965. Effect of fire on bunchgrasses of the sagebrush-grass region in southern Idaho. Ecology 46:680-688.
Wright, H. A. 1971. Why squirreltail is more tolerant to burning than needle-and-thread. Journal of Range Management 24:277-284.
Contributors
DBP/GKB
P NovakEchenique
T StringhamRangeland health reference sheet
Interpreting Indicators of Rangeland Health is a qualitative assessment protocol used to determine ecosystem condition based on benchmark characteristics described in the Reference Sheet. A suite of 17 (or more) indicators are typically considered in an assessment. The ecological site(s) representative of an assessment location must be known prior to applying the protocol and must be verified based on soils and climate. Current plant community cannot be used to identify the ecological site.
Author(s)/participant(s) Contact for lead author Date Approved by Approval date Composition (Indicators 10 and 12) based on Annual Production Indicators
-
Number and extent of rills:
-
Presence of water flow patterns:
-
Number and height of erosional pedestals or terracettes:
-
Bare ground from Ecological Site Description or other studies (rock, litter, lichen, moss, plant canopy are not bare ground):
-
Number of gullies and erosion associated with gullies:
-
Extent of wind scoured, blowouts and/or depositional areas:
-
Amount of litter movement (describe size and distance expected to travel):
-
Soil surface (top few mm) resistance to erosion (stability values are averages - most sites will show a range of values):
-
Soil surface structure and SOM content (include type of structure and A-horizon color and thickness):
-
Effect of community phase composition (relative proportion of different functional groups) and spatial distribution on infiltration and runoff:
-
Presence and thickness of compaction layer (usually none; describe soil profile features which may be mistaken for compaction on this site):
-
Functional/Structural Groups (list in order of descending dominance by above-ground annual-production or live foliar cover using symbols: >>, >, = to indicate much greater than, greater than, and equal to):
Dominant:
Sub-dominant:
Other:
Additional:
-
Amount of plant mortality and decadence (include which functional groups are expected to show mortality or decadence):
-
Average percent litter cover (%) and depth ( in):
-
Expected annual annual-production (this is TOTAL above-ground annual-production, not just forage annual-production):
-
Potential invasive (including noxious) species (native and non-native). List species which BOTH characterize degraded states and have the potential to become a dominant or co-dominant species on the ecological site if their future establishment and growth is not actively controlled by management interventions. Species that become dominant for only one to several years (e.g., short-term response to drought or wildfire) are not invasive plants. Note that unlike other indicators, we are describing what is NOT expected in the reference state for the ecological site:
-
Perennial plant reproductive capability:
Print Options
Sections
Font
AAAAOther
PrintThe Ecosystem Dynamics Interpretive Tool is an information system framework developed by the USDA-ARS Jornada Experimental Range, USDA Natural Resources Conservation Service, and New Mexico State University.
Accessibility statement
