Integrating Concepts of Ecological Sites, State-and-Transition Models, Rangeland Health, and NRCS Conservation Planning

On the Ground Resource managers are challenged to inventory and assess the condition of rangeland ecosystems, determine any existing management problems, implement management plans developed to correct problems and improve conditions, and predict and monitor changes in conditions. Ecological site descriptions, state-and-transition models, and rangeland health assessments are three powerful tools to help managers understand current and potential conditions, describe resource concerns, and develop conservation plans to achieve desired conditions. Resource concern risk ratings are a new feature of ecological site descriptions that enhance the integration of these tools and resources.


Introduction
Two dominant and related concepts have emerged in the field of rangeland management.First, Ecological Sites (ES), the systematic classification and description of spatial and temporal variation in rangeland ecosystems with their attendant state-and-transition models (ST M). S econd, Rangeland Health (RH), the application of a standardized rapid assessment protocol to determine the functional status of a defined area of rangeland have been adopted by a broad cross-section of public and private landowners and managers as a basis for decision support and communication.Despite widespread acceptance and application within the profession, the integration of these concepts at the operational scale frequently suffers within the constraints of agency implementation.Privateland financial and technical assistance programs, generally managed by the US Natural Resources Conservation Service (NRCS) have different legal and regulatory requirements compared with public lands administered by the US Department of Agriculture Forest Service (USDA-FS) and the Bureau of Land Management (BLM).Likewise, state-owned lands may have different decision-making criteria.However, all rangeland conservation planning and management is fundamentally similar and relies on an accepted site description to inventory current site-specific conditions, evaluate alternatives, establish objectives, implement management actions, monitor responses, and adjust.Thus, the site description and health assessment process are the objective basis for rangeland management in the United States.
In this paper, we demonstrate the integration of the ES and RH concepts within the context of the NRCS conservation planning process.In particular, we examine the links among ES, RH, and resource concerns in the inventory, objective setting, and management practice implementation.Resource concerns are used by NRCS to evaluate the effectiveness of conservation programs and policy decisions.Although other agencies and land management organizations have different legal and regulatory context, our goal is to demonstrate the link between those administrative peculiarities and the basic information for conservation planning and evaluation for a specific rangeland ecosystem.

Geographic context
Major Land Resource Area (MLRA) 28A Ancient Lake Bonneville occurs in Utah, Nevada, and Idaho ( Fig. 1 ).It covers about 95,246 km 2 (36,775 square miles).This area is the farthest eastern extent of the Great Basin Section of the Basin 2023 Figure 1.Location map and general aspect photo of Major Land Resource Area (MLRA) 028A Ancient Lake Bonneville. 3 .
and Range Province of the Intermontane Plateaus.It is an area of nearly level basins between widely separated mountain ranges trending north to south.Elevation ranges from 1,204 to 2,000 m (3,950 to 6,560 feet) in the basins and from 1,996 to 3,398 m (6,560 to 11,150 feet) in the mountains.The average annual precipitation is 13 to 30 cm (5 to 12 inches) in the valleys and is as much as 124 cm (49 inches) in the mountains.The dominant soils in the area have a mesic or frigid soil temperature regime, an aridic or xeric soil moisture regime, and mixed mineralogy.There are more than 100 ESs described in this MLRA encompassing a wide range of soil and climate attributes and vegetation behaviors.There are a range of conditions that confront managers working in this MLRA ( Table 1 ).

Concepts and case study
To demonstrate and document the planning process, we used a tool set adopted by NRCS, BLM, and USDA-FS for rangelands: Ecological Site Descriptions (ESDs), STMs, and RH Indicators. 1 Rangeland landscapes are classified into ESs for the purposes of inventory, evaluation, and management.An ES is a conceptual landscape division, defined as a distinctive kind of land, based on recurring soil, landform, hydrolog y, geolog y, and climate characteristics.ESs are unique in their ability to produce distinctive types and amounts of vegetation and response to management actions and natural disturbances. 2An ES is the product of all the biotic and abiotic environmental factors responsible for its development.It has a set of biotic and abiotic characteristics that have contributed to site development over time.These and other factors interact to create the characteristics that differentiate one ES from another.The same ES should be found on the landscape wherever the same prevailing biotic and abiotic characteristics occur.

Ecological site description
An ESD is the reference document that organizes information and data about a particular ES.ESDs function as a primar y repositor y of ecological and management supporting information and accumulated knowledge regarding ESs. 3 To better understand how environmental factors are expressed on the landscape and can be used to differentiate ESs, consider five ESs in MLRA 28A ( Table 1 ).Species composition and production differences among these five ESs is driven by the amount of precipitation, high water tables, soil chemistry, and soil texture.The range in attributes shows the importance of selecting the correct ESD for management guidance ( Table 1 ).Differences in plant composition, production, and ecological processes can dramatically affect site response to management actions.These climate and soil properties and the vegetation responses are common across all land ownerships in the region.Management concerns reflect, in large part, the physical setting.Management responses, likewise, are constrained by the ecological processes and economic realities of extensive land use in an arid environment.

State-and-transition model
A STM is an integral part of an ESD.Each model depicts different plant associations occurring on an ES and communicates complex ecological information about vegetation response to disturbances and management ( Fig. 2 ).States (large boxes bounded by solid, dark lines) represent one or more plant communities (small boxes with solid, light lines).States are relatively stable and resistant to disturbances up to a threshold point (represented by the boundary of the large boxes).Changes within a state, referred to as community pathways, are naturally occurring and predictable responses of the plant communities to the natural range of variability in environmental characteristics (such as drought or wet conditions) and disturbances (such as the occurrence of fire) or management associated with the site.
A transition is the trajectory of change between states, illustrated by a line leading from one state to another (i.e., from State 1 to State 2; Fig. 2 )."Transitions are the sum of changes in biotic or abiotic influences or events, acting independently or in combination, that contribute directly to loss of resilience of a state and result in change to another state."(p.631-A.8) 2 Transitions are described in terms of controlling variables, triggering events, feedbacks, and thresholds.A reference state, often containing multiple plant communities, is included in the STM contained within the ESD ( Fig. 2 ).The reference state has traditionally been defined as the plant community at Anglo-European settlement, though other criteria that existed during the 500-year or shorter period immediately preceding European settlement may be used. 2Included in the description of the reference state are community-scale vegetation attributes, dynamic soil properties, and animal communities dependent on a c lear ly defined disturbance regime that reinforce the continued function of the ecological state through their interactions. 3nderstanding the ecological structure and processes associated with a transition, particularly from a state considered to be of higher value to a state of lower value, is vital for resource managers.This knowledge is necessary to assess risks associated with undesirable change, target high-priority areas for intensive management, understand time scales, and plan appropriate management actions. 4 , 5e use an example STM for the Upland Gravelly Loam (028AY307UT) ES in MLRA 28A ( Fig. 2 ).The STM represents our current knowledge of the ecological dynamics of this site.As with other information in ESDs, STMs will change as additional information becomes available. 6he description of the reference state (State 1) for the Upland Gravelly Loam site consists of three recognizable communities and the pathways of change that occur among them ( Fig. 2 ).Community 1.2 is a Wyoming big sagebrush ( Artemisia tridentata ssp.wyomingensis ) and cool-season grassdominated community after long periods without fire (pathway 1.1b).Community 1.3 is a cool-season grass-dominated community after a fire or other disturbance that kills the sagebrush (pathways 1.1a and 1.2a).Community 1.1 is a coolseason grass and Wyoming big sagebrush community that develops through succession as sagebrush reestablishes after a fire (pathway 1.3a).The vegetation for these three communities is considered to be most in balance with the long-term environmental factors and natural disturbances associated with the Upland Gravelly Loam ES and represent the current understanding of the reference state ( Fig. 2 ).
Transitions from the reference to other states on the Upland Gravelly Loam site are due to disturbances outside the natural range of variability, including livestock grazing, change in fire frequency and intensity, conifer expansion, and introductions of non-native plant species.The introduction of non-native species causes the transition from State  the inclusion of non-native species.There is no known way to effectively remove these plants from the site once they have become established.Non-native plants are present in this state and do not dominate the plant community or drive ecological processes, but their presence has reduced site resiliency.This state is irreversibly changed from the reference state.
Long-term heavy grazing in late spring and summer and the lack of fire ( > 100-year intervals) (Transition T2a) will result in reduced perennial grasses and shrubs, with Utah juniper ( Juniperus osteosperma ) becoming dominant (State 3; Fig. 2 ).Invasion of these trees into adjacent ESs is common, with the likelihood of invasion increasing with time.
Long-term continuous grazing in late spring and summer in the absence of a Utah juniper seed source (Transitions T2b and T1b) will result in a reduction of perennial mid-grasses and an increase of broom snakeweed ( Gutierrezia sarothrae ; State 4; Fig. 2 ).Increased severity of grazing pressure, mechanical disturbance, or very frequent and severe fires ( < 8-year intervals; Transitions T3b, T4b and T2c) will result in dominance of invasive annuals, typically cheatgrass ( Bromus tectorum ), with the possibility of annual monocultures (State 5).
Rangeland seedings using non-native perennial grasses (Transitions T3a, T4a, and T5a; Fig. 2 ) result in a low diversity plant community (State 6).With good grazing management and native plants included in the seed mix (or recruitment from adjacent seed sources), natives may co-dominate the site long term (Transition R6a), leading back to State 2.

Rangeland health
RH is a concept developed in the mid-1990s in response to ongoing discussions within the rangeland management profession about evaluating rangeland resources. 7The SRM glossary of terms 8 defines RH as: The degree to which the integrity of the soil, the vegetation, the water, and air as well as the ecological processes of the rangeland ecosystem is balanced and sustained.Integrity is defined as: Maintenance of the structure and functional attributes characteristic of a particular locale, including normal variability.The Interpreting Indicators of RH (IIRH) technical reference states "The IIRH protocol is primarily a qualitative assessment of ecological processes using 17 observable indicators to assess ecological processes on a site, most of which can be supported by appropriate quantitative measures."(p.4). 1 A well-developed ESD is needed to apply IIRH protocol.The ESD indicates the reference state, which functions at a sustainable/resilient level under the natural disturbance regime.This reference state is often made up of more than one community phase. 1 A reference description is developed for each of the 17 indicators.These descriptions are compiled in the RH reference sheet.Once developed, the RH reference sheet becomes part of each ESD.
The IIRH assessment is unique because the indicators are organized into a system for the RH assessment to ask many important questions about the structure and function of a specific ES. 1 Overlap in the questions asked by the indicators alleviates some observer bias by helping resource managers using the indicators reach similar conclusions.For instance, it is challenging to differentiate between rills (indicator 1) and water flow patterns (indicator 2).One resource manager conducting a RH assessment on an ES may record more rills than would be expected for the site but fewer water flow patterns.In contrast, another resource manager may report the opposite.When this information is interpreted, both individuals report that there is evidence of more water movement than expected for the site raising concern about the hydrologic function or soil and site stability of the area.
There is redundancy built into the indicators so that the same or similar questions about RH are asked differently. 1 For example, compaction layer (indicator 11), soil surface resistance to erosion (indicator 8), and soil surface loss and degradation (indicator 9) are all indicators to help determine if an evaluation area is more susceptible to loss of soil and site stability (from runoff and soil erosion) than would be indicated by the reference conditions.The assessment of RH is based more on whether the ratings of the redundant indicators are similar than on the rating of individual indicators.For instance, if soil cover as indicated by bare ground (indicator 4), effects of plant community composition and distribution on infiltration (indicator 10), and litter cover and depth (indicator 14) are lower than expected, this suggests there is not sufficient cover or arrangement of plants on the landscape to reduce runoff and erosion.The indicators that evaluate soil movement (rills, indicator 1; pedestals and/or terracettes, indicator 3; gullies, indicator 5; and wind-scoured and/or depositional areas, indicator 6) will determine the seriousness and type of problem.In another example,if the ratings for pedestals and/or terracettes (indicator 3), wind-scoured and/or depositional areas (indicator 6), and soil surface loss and degradation (indicator 9) are poorer than expected, this is evidence of degradation from wind erosion.
The RH assessment for an ES describes the departure of each of the 17 indicators from the reference condition.Once each indicator has been assigned as none-to-slight, slightto-moderate, moderate, moderate-to-extreme, or extreme-tototal departure from the reference condition, the composite is used to estimate the departure of three RH attributes.Some of the indicators relate to only one attribute (for example, invasive plants indicator 16 only applies to biotic integrity), but most of the indicators provide information useful for interpreting more than one of the attributes (e.g., soil surface loss and degradation, indicator 9, is an indicator of the health of all three attributes).
The product of a RH assessment is the evaluation of these three attributes ( Table 2 ) rather than the 17 indicators.The evaluation process requires resource managers conducting the assessment to determine the level of departure of the actual condition with respect to the reference condition.Once all 17 indicators are assessed, the results are recorded in an evaluation sheet with the rating of each indicator associated with the appropriate attributes.Typically, the attribute ratings are based on which rating scales have the most indicators but may be adjusted because the evaluator weighs one or more indicators being sufficiently important to justify a shift in attribute rating, using a preponderance of evidence approach.The final ratings are based on the indicator ratings, knowledge of ES properties and processes, and importance of the indicators.
Possibly the most revealing outcome of a RH assessment is when > 1 attribute ratings tend toward "moderate" because this indicates resource concerns have been found, but the degree of degradation has not reached a level where improvement through management is unlikely.The moderate and slight-to-moderate rating should serve as an early warning that the site's health is at risk and needs management attention.Sites assessed as moderate should have high priority for additional study and monitoring to determine trend with 2023 The capacity of an area to limit redistribution and loss of soil resources (including nutrients and organic matter) by wind and water and to recover this capacity when a reduction does occur.Hydrologic function 10 The capacity of an area to capture, store, and safely release water from rainfall, run-on, and snowmelt; to resist a reduction in this capacity; and to recover this capacity when a reduction does occur.Biotic integrity 9 The capacity of the biotic community to support ecological processes within the normal range of variability expected for the site, to resist loss of the capacity to support these processes, and to recover this capacity when losses do occur.
quantitative techniques. 9If the departure rating is associated with a site recovering from a more deteriorated condition, this would indicate an upward trend and that the current management is appropriate.If the site shows signs of active deterioration (downward trend), current management may need adjusting.
Attribute ratings may indicate different departure levels from reference conditions.For example, a site where the biotic integrity attribute is significantly departed from reference condition may still have healthy soil and site stability and hydrologic function.This provides crucial information because it shows the soil, site, and hydrologic potential remain healthy, indicating an opportunity to improve the health of the plant community.Rangeland improvement is more complex and costly when the soil and site stability or hydrologic function are considered unhealthy because these resources could be seriously degraded.
The RH ratings for soil and site stability, hydrologic function, and biologic integrity are not added together to provide a site rating.The value of RH is to determine if any of the attributes indicate a problem.An example of an adept application of IIRH to a landscape can be seen in Jablonski et al. 10 Because interpreting indicators of RH is a qualitative method of evaluating rangeland conditions, it cannot be used for monitoring.It is inappropriate to conduct an RH assessment at two different time periods and conclude the trend for biological integrity was downward because the second assessment indicated a moderate departure from the reference compared with the slight-to-moderate rating for the first assessment.These differences in the attribute ratings may represent deterioration in the site or represent observer bias (i.e., differences in how the resource managers doing the rating viewed departure from the reference conditions). 11Both ratings indicate, however, potentially important deviation from the reference conditions and suggest the site needs additional evaluation.

NRCS conservation planning
The NRCS uses a 9-step, 3-phase conservation planning process 12 to deliver technical assistance ( Fig. 3 ).A resource inventory is completed in Phase I of the planning process, relying on communication with the landowner/operator,  12 A resource inventory is completed in Phase I of the planning process with input from the landowner/operator, referencing existing information (i.e., soil surveys, ESs, state or local resource assessments, etc.), and including field observations.During Phase II of the planning process, alternatives are developed with the goal of meeting the planning criteria.Phase III includes plan implementation, monitoring, and evaluation.
referencing existing information (i.e., soil surveys, ESs, state or local resource assessments, etc.), and referencing field observations.The inventory data are used to identify the resource concerns.A resource concern is the resource condition that does not meet minimum acceptable condition levels as established by resource planning criteria. 13Resource concerns are identified by comparing present existing conditions with the planning criteria established for the resource concern using various assessment methods, including automated assessment procedures, such as IIRH.There are currently 47 resource concerns, organized into the general categories of soil, water, air, plants, animals, energy, and humans (SWAPAE + H) that NRCS uses to categorize, identify, describe, and anal y ze resource concerns.Each has planning criteria, a quantitative or qualitative standard to be met, used to determine the Resource Concern's presence (or absence).
During Phase II of the planning process, alternatives are developed with the goal of meeting the planning criteria.Conservation planning on rangelands uses ESDs and IIRH in the "Inventory Resources"and "Anal y ze Resource Data"steps.ESDs inform the planner about the site's potential, which establishes the basic inventory and later guides alternative development in Phase II.The RH assessment documents the 17 indicators and determines the attribute ratings.The attribute ratings are applied to the list of resource concerns to determine if the planning criteria are met.The planning criteria for 13 of the SWAPAE + H resource concerns are an IIRH attribute rating, an indicator rating, or some combination with a rating of at least slight to moderate or better ( Table 3 ).The plan is implemented in Phase III of the planning process, with monitoring included in the "Evaluate the Plan" step.The BLM Allotment Evaluation process and the NRCS conservation planning process are done at equivalent scales (e.g., one ranch or grazing allotment).The BLM uses the national fundamentals of RH (43 CFR 4180.2) that must address minimum standards.These standards are further refined regionally into Land Health Standards.IIRH is commonly incorporated into these regional Land Health Standards.To evaluate land health, BLM field offices conduct on-the-ground evaluations of these standards in grazing allotments. 14The BLM Assessment, Inventory and Monitoring framework relies on ES concepts to stratify sampling and analyses. 15From a planning and implementation perspective, BLM uses ES information and IIRH protocols to set goals and track progress. 16ome NRCS resource concerns are obvious and readily apparent from cursory field observations.Others require skill and experience to recognize in the field.If the risk of re-source concerns being present were formally identified in the STM's various states and plant communities, the time and effort spent to document resource concerns could be reduced.
The information contained in an ESD can determine the likely outcome of an IIRH assessment and the probability of the need to address a resource concern.Kachergis et al. 17 found some states are consistently related to deviations from reference conditions based on RH indicators.For example, the STM for the Upland Gravelly Loam ES in MLRA 28A ( Fig. 2 ), state 5, is highl y likel y to be worse than slight to moderate for biotic integrity because it is dominated by invasive plants, indicating a plant resource concern.In state 3, dominance of Utah juniper with a sparse understory is very likely to be worse than slight to moderate for all 3 attributes, indicating plant, soil, and water resource concerns ( Fig. 4 , Table 4 ).
A resource concern risk assessment is available for data entry when editing an ESD in the Ecological Dynamics Interpretive Tool (EDIT) database 3 using the "model builder" (for STMs) and populating the database at the state or plant community level.To complete the data entry requires using a set of guidelines to indicate high (red), medium (yellow), or low (green) for the SWAPAE + H resource concerns ( Fig. 4 ).The high, medium, or low ratings represent the probability of a resource concern for a specific state or plant community.Only one resource concern in a SWAPAE + H category must be present to indicate risk in the STM.The resource concern(s) A resource concern is the resource condition not meeting minimum acceptable condition levels as established by resource planning criteria. 13esource concerns are identified by evaluating present existing conditions with the planning criteria established for the resource concern using various assessment methods, including Interpreting Indicators of Rangeland Health (IIRH).Currently 47 resource concerns are organized into the general categories of soil (S), water (W), air (A), plants (P), animals (A), energy (E), and humans (H; SWAPAE + H) that NRCS uses to categorize, identify, describe, and analyze resource concerns.Guidelines indicate high (red), medium (yellow), or low (green) risk for the SWAPAE + H resource concern.The high, medium, or low ratings represent the probability of a resource concern for a specific state or plant community and only one resource concern in a SWAPAE + H category must be present to indicate risk in the state-and-transition model (STM).Green indicates the probable absence and red the probable presence of a Resource Concern.Yellow indicates uncertainty, and a Rangeland Health (RH) assessment is needed.4 ). 3 With this formal recognition of resource concerns attached to states and plant communities in the STM, NRCS conservation planners only identify the ES and where each planning unit is on the STM as a first step to identifying potential resource concerns.Green indicates the probable absence and red the probable presence of a resource concern.Yellow indicates uncertainty, and in these cases, a RH assessment needs to be completed.Including resource concern risks in STMs improves the efficiency of field time spent on conservation planning inventory and assessment, better enables novice planners to detect resource concerns, and makes STMs more relevant and useful in conservation planning.

Summary and management implications
Conducting inventory and assessment, anal y zing data to identify specific resource problems, predicting the outcome of management alternatives, and monitoring results on rangeland ecosystems are challenging tasks.ESDs, STMs, and RH assessments are three powerful tools to help managers understand current and potential conditions, describe resource concerns, and develop conservation plans to achieve desired conditions.Within the framework of the NRCS conservation planning process, these tools are integrated to ensure the best available information is utilized when assisting landowners.Resource concern risk ratings are a new feature of ESDs enhancing the integration of these tools and resources.
The ESD, STM (with its resource concern risk ratings), and the RH reference sheet we describe provide essential information about ESs.These can be used for inventory, planning, management, monitoring, and throughout the NRCS planning process.The ESDs provide information about each unique site in a management area.Such information is necessary to interpret how sites may respond to management actions compared with other sites in the same area.At larger scales, they also inform how management affects an area that includes multiple sites with different soils, topography, cli-mate, and expected plant community composition, production, and disturbance regimes.
An STM is an integral part of a site description because the model describes the different plant states and communities found on an ES, the ecological relationships existing between the states and communities, the ecological and management factors associated with each state and community (including transitions and thresholds that affect management options), and the processes described in the Ecological Dynamics section of the ESD that cause communities to change.The state, community, transition, and threshold descriptions include information about the plant community, dynamic soil properties, hydrology, and resource concerns.Knowing which states and communities are possible on a site allows a manager to set realistic objectives for the desired species composition and production.
The STM informs the manager about potential challenges encountered in achieving management goals, such as transitions crossing thresholds that indicate significant changes in plant composition, changes in fire occurrence, and invasion of non-native plants.The manager learns that some plant communities may not be a realistic goal given the resources available and furthermore, that some management actions may be needed to improve rangeland condition and productivity.
The STM provides information about changes that, once initiated, are likely to continue until a new steady state is reached or management actions designed to stop or redirect the change are initiated.Understanding the processes of change allows the manager to determine when current management is sustaining the site in the desired condition or when it is causing desired or undesired change.
For field inventory procedures, merely identifying the ES, state, and plant community may be adequate to document some resource concerns where the site description contains a completed resource concern risk assessment.The planner and manager can then determine the state and community being managed and the ecological process and likely disturbances (natural and human-caused) that may have led to the current state and community.This approach of observing ecological states and ascribing resource concern risks (i.e., threats) for assessment purposes has been used for land health assessment on public lands. 18his approach may not be appropriate for all applications of IIRH.When additional certainty is desired, a RH assessment, or other appropriate tools, may be conducted.Quantitative techniques provide more certainty.An IIRH assessment identifies areas functioning at a level that can sustain productivity and use, areas at risk of changing that threatens stability but retains the potential for improvement, and areas at a level of deterioration that improvement will be difficult and costly.This information helps the manager set priorities for treatments to achieve the greatest benefit for investment and set priorities for intensive monitoring to determine if management changes are needed.
In this paper, we demonstrated how ESDs and their constituent STMs can be used to support the general process of land management assessment and planning.When com-bined with site-specific assessment tools such as IIRH, this framework supports decision-making and communication at a scale relevant to individual properties and allotments.Finally, this integration of general and site-specific tools can be enhanced with agency and program specific information to support assessment and reporting.The concepts and tools are well-proven and technically sound and the administrative management tools are readily available and accessible.Continued development and refinement of these concepts and tools will establish a basis for accessible, reliable ecological information for managers.

Declaration of Competing Interest
The authors declare the following financial interests/personal relationships which may be considered as potential competing interests.The authors certify that they have no financial interest in the subject matter discussed in the manuscript.S.A.G is an employee of USDA Natural Resources Conservation Service and is associated with management decisions regarding the topic of this manuscript.
1 to State 2 (Transition T1a; Fig 2 ).State 2 (Current Potential) includes all the plant communities existing in State 1 with

Figure 2 .
Figure 2. State-and-transition model (STM) for the Upland Gravelly Loam (Wyoming big sagebrush) ecological site (ES) R028AY307UT. 3Each STM depicts a plant association occurring on an ES and describes ecological information about vegetation response to disturbances and management.States, shown as boxes bounded by solid dark lines, represent one or more plant communities, which are shown as boxes with solid light lines.A transition is the trajectory of change between states, which is shown by a line leading from one state to another (i.e., from State 1 to State 2).A reference state, often containing multiple plant communities, is included in the STM.Included in the description of the reference state are community-scale vegetation attributes, dynamic soil properties, and animal communities dependent on a clearly defined disturbance regime.

Figure 3 .
Figure 3.The Natural Resource Conservation Service (NRCS) 9-Step 3-Phase Conservation Planning Process adapted from NRCS National Planning Procedures Handbook.12A resource inventory is completed in Phase I of the planning process with input from the landowner/operator, referencing existing information (i.e., soil surveys, ESs, state or local resource assessments, etc.), and including field observations.During Phase II of the planning process, alternatives are developed with the goal of meeting the planning criteria.Phase III includes plan implementation, monitoring, and evaluation.

Figure 4 .
Figure 4. Example of resource concern risk assessment for the Upland Gravelly Loam (Wyoming big sagebrush) ecological site (ES) R028AY307UT.A resource concern is the resource condition not meeting minimum acceptable condition levels as established by resource planning criteria.13Resource concerns are identified by evaluating present existing conditions with the planning criteria established for the resource concern using various assessment methods, including Interpreting Indicators of Rangeland Health (IIRH).Currently 47 resource concerns are organized into the general categories of soil (S), water (W), air (A), plants (P), animals (A), energy (E), and humans (H; SWAPAE + H) that NRCS uses to categorize, identify, describe, and analyze resource concerns.Guidelines indicate high (red), medium (yellow), or low (green) risk for the SWAPAE + H resource concern.The high, medium, or low ratings represent the probability of a resource concern for a specific state or plant community and only one resource concern in a SWAPAE + H category must be present to indicate risk in the state-and-transition model (STM).Green indicates the probable absence and red the probable presence of a Resource Concern.Yellow indicates uncertainty, and a Rangeland Health (RH) assessment is needed.

Table 1
Attributes of five ecological sites in Major Land Resource Area (MLRA) 28A Ancient Lake Bonneville 3 .

Table 3
13CS resource concerns and planning criteria that use Interpreting Indicators of Rangeland Health as the assessment tool13.Biotic Integrity attribute: slight to moderate departure or less AND indicators: Functional Structural Groups 12, Dead or Dying Plants or Plant Parts 13, Annual Production 15, and Vigor with an emphasis on Reproductive Capability of Perennial Plants 17; indicators: slight to moderate or less Plant structure and composition Biotic integrity: slight to moderate or less AND Functional Structural Groups indicator 12: slight to moderate or less Plant pest pressure Biotic Integrity: slight to moderate or less AND Invasive Plants indicator 16: slight to moderate or less Animals Feed and forage imbalance * Biotic integrity: slight to moderate or less AND Annual Production indicator 15: slight to moderate or less * Additional assessment tools are required beyond IIRH.IIRH indicates Interpreting Indicators of Rangeland Health.

Table 4
1xamples of resource concerns for the Upland Gravelly Loam ecological site R028AY307UT3.Note.High risk resource concerns are bolded.Medium risk resource concerns are not bolded.Low risk resource concerns are omitted.Rangeland health (RH) attributes and indicators likely to be assessed as moderate or worse.Numbers in parentheses correspond to the indicator number in the IIRH technical reference.1arelisted in the EDIT database dominant resource concerns checklist ( Table *