State 1
Reference

The Saline Subirrigated ecological site is a wet site that hosts a mixture of sedges and grasses, as well as a minor component of shrubs. The communities that represent the reference communities are native driven. Disturbances and the natural hydrologic processes involved in these generally riparian communities will affect which community is occurring along a landscape gradient. In communities not tied to a riparian system, the same shift in species will occur with the shift in the water table over time.

Characteristics and indicators. Alkali sacaton, Nuttall's alkaligrass, alkali bluegrass, and inland saltgrass are dominant with Nebraska sedge, beaked sedge, and baltic rush. Common shrubs in this community is greasewood, wild rose, shrubby cinquefoil, and on occasion willows. As a community is in drier stages or degrades, foxtail barley, little barley and ryegrass are common.

Resilience management. The wet nature of this community creates a fragile community that is easily altered with management pressures. The community is also resilient because of the wet nature and the significant freeze and thaw cycles common to this higher elevation soil. The salt-laden characteristic of these soils limits resiliency slightly, but the community does have the potential to recover after disturbance.

Community 1.1
Alkali Sacaton/ Nuttall's Alkaligrass

Figure 8. A diverse community is present, but with the loss of ground water, sedges and other key species are starting to recede.

The interpretive plant community for this site is the Reference Community phase. This state evolved with grazing by large herbivores, periodic fires, supplemental moisture, and saline and/or alkali soils. Potential vegetation is 80 percent grasses or grass-likes, 5 percent forbs and 15 percent woody plants. The major grasses include alkali sacaton, Nuttall’s alkaligrass, alkali cordgrass, and Canada wildrye. Grasses of secondary importance are Baltic rush, Chairmaker’s bulrush, alkali bluegrass, and inland saltgrass. Woody plants are primarily greasewood and shrubby cinquefoil. A variety of forbs also occurs in this state and plant diversity is high (see Plant Composition Table).

The total annual production (air-dry weight) of this state is about 3800 pounds per acre, but it can range from about 3200 lbs./acre in unfavorable years to about 4400 lbs./acre in above average years.

Resilience management. The state is stable and well adapted to the climate. The diversity in plant species and the reliable water table allow for high drought resistance. This is a sustainable plant community (site/soil stability, watershed function, and biologic integrity).

Community 1.2
Alkali Sacaton/Inland Saltgrass/Mixed Shrub

Figure 11. Alkali sacaton, with a alkali bluegrass and inland saltgrass understory. Shrubs have been removed from this site.

Historically, this plant community evolved under moderate grazing by domestic livestock and low fire frequency. Currently, this site is normally found under a moderate, season-long grazing regime and in the absence of fire or brush control. Prolonged drought can also play an important role and will exacerbate these conditions. Saline and flood tolerant perennial plants make up the dominant species in this plant community.

The dominant grasses include alkali sacaton, inland saltgrass, alkali bluegrass, and Baltic rush. Forbs commonly found in this plant community include alkali seepweed, silverweed, American licorice, seaside arrowgrass, and smooth horsetail. Greasewood and rose comprise the majority of the woody species and make up less than 25 percent of the annual production.

When compared to the Reference Community Phase, Canada wildrye, Nuttall’s alkaligrass, alkali cordgrass, and Nebraska sedge have decreased. Inland saltgrass, forbs, and greasewood, have increased.

The total annual production (air-dry weight) of this state is about 3200 pounds per acre, but it can range from about 2800 lbs./acre in unfavorable years to about 3600 lbs./acre in above average years.

Resilience management. This state is stable and protected from excessive erosion. The herbaceous component is mostly intact and plant vigor and replacement capabilities are sufficient. Only minimal occurrences of water flow patterns and litter movement is evident. Incidence of pedestalling is minimal. Soils are mostly stable and the surface shows minimum soil loss. The watershed is functioning and the biotic community is intact.

Community 1.3
Inland Saltgrass /Greasewood

This plant community is the result of frequent and severe grazing with periodic overflows. This plant community is dominated by a dense short grass sod and includes a mosaic shrub overstory. Greasewood, the primary shrub, comprises less than 25 percent of the annual production, and shrub numbers are kept in check by the herbaceous understory.

The dominant grasses are inland saltgrass, alkali bluegrass, Baltic rush and Chairmaker's bulrush. Forbs such as seaside arrowgrass, American licorice, curly dock, and smooth horsetail are common. Greasewood is the primary overstory species in this plant community. Plant diversity is moderate to poor.

When compared to the Reference Community Phase, the tall and mid-stature grasses are significantly reduced or absent. Short-stature warm-season grasses are dominant and less desirable native grasses are common (foxtail barley and little barley). Shrubs will have increased as a percentage of the total production, but will not dominate as the sod prevents a homogeneous shrub cover. Areas of bare ground may have increased in patches, and total production has decreased as the short grasses have replaced the tall and mid-stature grasses.

The total annual production (air-dry weight) of this state is about 1800 pounds per acre, but it can range from about 1400 lbs./acre in unfavorable years to about 2200 lbs./acre in above average years.

Resilience management. The sod component of this plant community is extremely resistant to change and continued frequent and severe grazing or the removal of grazing does not seem to affect the plant composition or structure of the plant community. The biotic integrity of this state is generally not functional as plant diversity is poor, especially the amount of herbaceous species. The vegetative structure has shifted as the shrubs and short-stature grasses now occupy the majority of the site. This sod bound plant community is very resistant to water infiltration. While this sod protects the site itself, excessive runoff increases erosion on bare ground and can cause rill channels and gully erosion. Water flow patterns are obvious in the bare ground areas and shrubs and sod patches are pedestalled. Rill channels are noticeable in the interspaces and gullies may be establishing where rills have concentrated. The watershed may not be functioning, as runoff is excessive and erosional processes are accelerated.

Pathway 1.1A
Community 1.1 to 1.2

Alkali Sacaton/ Nuttall's Alkaligrass

Alkali Sacaton/Inland Saltgrass/Mixed Shrub

Moderate, continuous season-long grazing will convert this plant community to the Alkali Sacaton/Inland Saltgrass/Mixed Shrub Plant Community. Prolonged drought will exacerbate this transition. Continuous grazing pressure weakens the key species targeted by grazing animals, which include Canda wildrye and Nuttall's alkaligrass, while encouraging inland saltgrass.

Pathway 1.2A
Community 1.2 to 1.1

Alkali Sacaton/Inland Saltgrass/Mixed Shrub

Alkali Sacaton/ Nuttall's Alkaligrass

Prescribed grazing or possibly long-term prescribed grazing will result in a plant community very similar to the Reference Community Phase, except that greasewood will persist without some form of brush control.

Pathway 1.2B
Community 1.2 to 1.3

Frequent and Severe grazing will convert this plant community to the Inland Saltgrass Sod/Greasewood Plant Community. Fire or mowing of the area may increase the greasewood cover, and will encourage inland saltgrass and other tillering and low-stature species.

State 2
Invaded

Increased activity on the landscapes provides more opportunity for disturbances as well as an increase of non-native species seed source. Disturbances to the soil surface and exiting canopy cover provides opportunity for non-native species to establish.

The most prevelant invader on saline sites is foxtail barley, redtop bentgrass, and occasionaly Kentucky bluegrass on these subirrigated sites. There are instances where these communities cross on the landscape, and they are at-risk of further transformation. The occurrence of these communities can be a process of time or of disturbance.

Historic studies have documented the presence of non-native species such as Kentucky bluegrass and dandelions prior to the early 1950's. Another concern is the threat of large scale weed invasions. Currently, most of the mountain has retained only small or isolated patches of invasive weeds. Areas of leafy spurge, toadflax (yellow or dalmation) and thistles have been identified. Although early detection/rapid response techniques are applied for land management, limited resources make it difficult to track all current and new infestation sites. Overall, the weed infestation level is not seen as a critical concern, but the threat is growing and being monitored closely.

Characteristics and indicators. Non-native or tame species and invasive species are less of a concern on the salt-laden soils. There are, however, species that are salt-tolerant that will establish on the Saline Subirrigated ecological site, reducing or pushing native species out. The threshold that is crossed to indicate an invaded site is 5 percent composition by cover or by weight. The dominant non-native/invader species are Kentucky bluegrass, redtop bentgrass, thistles, toadflax (Dalmatian, yellow), and swanson's pea. As new species are found, this list will be adapted to include these species.

Resilience management. Non-native and invasive species are resistant to change and resilient following disturbances. This makes a stable community that is difficult to change without significant inputs. The salt-laden soils limit the type of treatment, access, and species adapted to help recovery of the Invaded Community. Kentucky bluegrass, smooth brome, and other non-native species have a high resiliency once they have established in a community. The management of the native species is difficult, and is dependent on what specific species composition exists in the individual community. The removal or treatment of encroaching woody species is best tackled when they occur at a low intensity, before they may be seen as a concern.

Community 2.1
Non-Native (Tame)

Figure 14. Smooth brome and Kentucky bluegrass encroachment in a community. Greasewood was removed for haying.

Non-Native (Tame) Community Phase has maintained a representative sample of the perennial grasses and forbs that are typical of the site with a mixed shrub community.
Non-native or tame species have established in the community and are a significant component (five percent or greater by foliar cover or weight), and are prominent (referring to a more wide scale composition, not one isolated patch in an isolated portion of the landscape).

Production of the desired perennial species is generally reduced but the total production is maintained or elevated due to the production potential of the non-native species. The species most common are Kentucky bluegrass, creeping meadow foxtail, redtop bent and common dandelion. However, smooth brome, meadow brome and timothy are possible components in areas with lower alkalinity.

Native species that are less desirable that are common to this community are foxtail barley, little barley, American licorice, and povertyweeds.

Resilience management. This plant community is resistant to change. These areas may be more prone to fire as fine fuels are more available. Plant diversity is moderate to poor. The plant vigor is diminished and replacement capabilities are limited due to the reduced number of native hydrophitic grasses. Plant litter is noticeably more when compared to reference communities due to the potential biomass produced by the non-native species (species dependent). Soil erosion is variable depending on the species of invasion and the litter accumulation thus associated, this variability also applies to water flow patterns and pedestalling. Infiltration is reduced and runoff is increased due to loss of perennial vegetation and root density.

Community 2.2
Invasive Invaded

Figure 15. Dense Canada thistle within a smooth brome and Kentucky bluegrass dominated community.

The Invasive Invaded Community Phase has maintained a fractured sample of the perennial grasses and forbs that are typical of the Saline Subirrigated ecological site, however there is a significant establishment of invasive species. This plant community evolved under frequent and severe grazing. The shrub component has been impacted and possibly removed by heavy browsing or human means. Weedy annuals and non-native species are the most dominant plants.

Invasive species, most commonly canada thistle, cockle bur, swainson's pea, and perennial pepperweed, hold a significant (5 percent or greater) composition on the landscape, and are prominent (referring to a more wide scale composition, not isolated patches on the landscape). Tamarisk or Russian olive as well as greasewood may be more abundant than other shrubs, as they are strong resprouters and may quickly re-establish the site after a disturbance.

With the decrease or loss of most desirable grasses, foxtail barley, little barley, inland saltgrass, and baltic rush will persist on the site. Creeping meadow foxtail, Kentucky bluegrass, redtop bentgrass, dandelion, and other introduced species will increase if present on the site. Other noxious weeds such as sow thistle may invade the site if a seed source is available. Production of the desired perennial species is generally reduced but the total production is maintained or elevated due to the production potential of the invasive species.

Resilience management. This plant community is resistant to continued herbivory. Annuals and invader species are effectively competing against the establishment of perennial cool-season grasses. Plant diversity is greatly altered and the herbaceous component is not intact. Recruitment of the major perennial grasses is not occurring and the replacement potential is low. The biotic integrity is missing. The state is unstable and is not protected from excessive erosion. Rill channels and gullies may be present on site and adjacent areas are impacted by excessive runoff. Water flow patterns and pedestalling are obvious. The watershed is not functioning.

Pathway 2.1A
Community 2.1 to 2.2

Non-Native (Tame)

Invasive Invaded

Seed sources are abundant for both non-native and for invasive invader species. Drought stress, ground/soil disturbance including impacts by grazing large herbivores or recreation create a niche for undesirable weeds to establish, even in the aggressive cover of tame invaders. Overland flow or irrigation practices can also serve as a seed source and means of establishing many invasive species in the community.

State 3
Disturbed

Although to a much smaller extent than in lower elevations, there are areas that have been accessed for irrigation convenience ditches or were part of a homestead. These areas have remnants of introduced species from haylands or have been left to recover and may be in varying stages of succession. There are areas that are heavily impacted by recreational vehicles, parking, trails, roadways, or other land disturbances that have reduced or removed most native perennial vegetation and left a highly disturbed land.

The Disturbed State could be drafted as a stand-alone box within the state and transition model diagram. No matter what state a site originally is ranked in, once the site is mechanically disturbed, or suffers a catastrophic or significant natural disaster that alters the soil properties (erosional, depositional, or chemical), the site potential is altered. The most prominent shift for this site tends to be a shift in the natural hydrology that is key to this site. This can include both the loss of or enhancement to the additional moisture to the site (seepage from irrigation ditches).

Mechanical disturbances and reclamation practices using non-native species could qualify some stages of this state to be considered as a land use shift. The result is the shift in potential and response in management so that it is no longer similar to the reference community. The potential shifts are highly variable, so a dynamic state was captured to highlight the altered communities that exist on the landscape.

Characteristics and indicators. The soil disturbance and mechanical or physical removal of the vegetative canopy is the key characteristic of the Disturbed State. The initial indicators are the primary successional species that establish following a disturbance including Russian thistle, kochia, and sunflowers. These initial colonizers will then be followed by any seeded species, or other species from within the locations seed bank.

Resilience management. The Disturbed State is highly variable and in a state of flux as the successional processes occur. Continued disturbance of these communities is a potential threat; and the communities are at high risk of transitioning to the Invaded State.

Community 3.1
Disturbed Lands

The title Disturbed Lands is encompassing two broad classifications of these land types. Go-back fields or tilled areas form Type one. The soils were once cultivated or were impacted by cultivation pracites and have since been left to natural processes. Homestead and abandoned farming sites can be identified on the landscape (through photo-tone shifts in aerial photographs) and are generally a mix of natives and introduced herbaceous species as well as trees. Cottonwood breaks, Russian Olive, and other species of trees on these sites are key markers of old homestead locations. These sites are generally isolated or small in nature and are difficult to reclaim due to the introduced species that persist on the landscape and the shift in hydrology. If reclaimed, they do not respond to the natural disturbance regimes in the same manner that a native, mechanically undisturbed site would respond. The Saline Subirrigated ecological site was incidental to disturbance by homesteading or irrigation processes. The extent of this type is limited on the landscape.

A subset of Type one are those areas that were or currently are being impacted by recreation - camp sites, trails, parking areas, roadways. The varying stages of healing once abandoned, or the level and age of disturbance at each location leave a variable community.

In a similar process, lands affected by energy development including transmission and transportation corridors provide a host of successional processes. Many times, these locations are re-exposed to disturbance frequently by mechanical means leaving annual weeds and primary successional species as the dominate canopy. Older, established sites or abandoned locations, have established communities similar to those expected on go-back fields and may be stable in nature.

The growth curve of this plant community will vary depending on the species that are selected for seeding. For a more accurate portrait of the growth curve for the seeded community, the species used and the climatic tendencies of the region must be considered.

Resilience management. The plant community is variable and depending on the age of the stand and the stage of successional tendencies that the location is in will determine how stable (resilient/resistant) the community is. Plant diversity is generally strong, but is usually lacking in the structural and functional groups that are desired on the site. Soil erosion is variable depending on the disturbance regime that is occurring on the site and will vary with the specific community that has established on a specific location. Site-specific evaluation is needed to determine the water flow and pedestalling as well as infiltration and runoff potential and associated risks for each community.

Transition T1A
State 1 to 2

Frequent and Severe grazing plus encroachment will convert this plant community to an Invaded State. Grazing reduces the vigor and cover of native cover, allowing aggressive non-native species to creep into a community. Soil disturbance and increased activity (by livestock, wildlife, or human) provide a seed source for invaders to establish.

Constraints to recovery.The aggressive nature of invader species limits the ability for a community to overcome their establishment. In many cases, control or removal has not been completed successfully without complete manipulation.

Context dependence.The presence of greasewood in the community will hinder the practices that are suited for vegetation treatments. Fire and mechanical disturbances to the surface vegetation will encourage the sprouting capabilities of greasewood and could compound the situation in some instances. The moisture content of the soil, water table depth, and extent of salt load may restrict access to treat the soils or to manipulate the vegetation on some locations.

Transition T1B
State 1 to 3

An abrupt or catastrophic disturbance will remove or significantly impact the native community and the soil structure, leaving a disturbed and barren site. With time, natural succession will begin the recovery process. However, the soil as well as hydrologic function has been altered in many cases, leaving a Disturbed State.

Constraints to recovery.The inability to restore hydrology or to replace soil stability in function (in the scope of significant head cuts or gullying) limits the recovery potential after significant disturbance.

Context dependence.Reclamation or restoration of the reference community is a challenge due to limitations of seed sources. Many of the species that are common in this community are established by sprig plantings only. Seedbed or site preparation is limited by the wetness of the soil, depth to water table and the soil textures. Access to these sites with equipment is difficult if not impossible for a large portion of the year.

Transition T3A
State 3 to 2

Once a site has transitioned to this state, the increased bare ground and weakened plant structure leaves the community for encroachment or species creep by non-native species such as Kentucky bluegrass, creeping meadow foxtail, and redtop. Thistles, toadflax, and houndstounge are quickly becoming significant problems on areas within these weakened plant communities. Increasing bare ground and weakening plant community structure leaves the community vulnerable to invader species such as toadflax and houndstongue.

Constraints to recovery.The inability to effectively eradicate the undesirable species is the known financially limiting constraint to this site recovering.