Rangeland Health Assessment

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					   Rangeland Health Assessment


2005 Conservation Security Program
                               Table of Contents

Introduction                                           page 1

Outline of steps for utilizing Rangeland Health        page 2
        Assessment within CSP

Flow chart of tasks to complete prior to signup        Page 3

Flow chart of process for conducting each              page 4
       Rangeland Health Assessment

Step 1. Identify the Evaluation Area, Determine        page 5
        Soil and Ecological Site (REQUIRED)

Step 2. Obtain or Develop the Reference Sheet          page 6
        (REQUIRED) and the Corresponding
        Evaluation Matrix (STRONGLY RECOMMENDED)

Step 3. Collect Supplementary Information              page 9

Step 4. Rate the 17 Indicators on the Evaluation       page 10
        Sheet (REQUIRED)

Step 5. Determining the Functional Status of the       page 11
        Three Rangeland Health Attributes (REQUIRED)

Adjustment and variances to be allowed                 page 12

Rangeland Health is defined as the degree to which the integrity of the soil,
vegetation, water, and air, as well as the ecological processes of the rangeland
ecosystem, are balanced and sustained.

A rangeland health assessment provides information on the functioning of
ecological processes relative to the reference state for the rangeland ecological
site. The assessment provides an indication of the status of the three attributes
chosen to represent the health of the “evaluation area” (i.e., the area where the
evaluation of the rangeland health attributes occur).

Ecological processes include the water cycle (the capture, storage, and
redistribution of precipitation), energy flow (conversion of sunlight to plant and
animal matter), and nutrient cycle (the cycle of nutrients such as nitrogen and
phosphorus through the physical and biotic components of the environment).

Ecological processes functioning within a normal range of variation will support
specific plant and animal communities. The product of this qualitative
assessment is not a single rating of rangeland health, but an assessment of the
three attributes. Definitions of these three closely interrelated attributes are:

Soil/Site Stability

The capacity of the site to limit redistribution and loss of soil resources (including
nutrients and organic matter) by wind and water.

Hydrologic Function

The capacity of the site to capture, store, and safely release water from rainfall,
run-on, and snowmelt (where relevant), to resist a reduction in this capacity, and
to recover this capacity following degradation.

Integrity of the Biotic Community

The capacity of the site to support characteristic functional and structural
communities in the context of normal variability, to resist loss of this function and
structure due to disturbance, and to recover following disturbance.

The following instructions are intended to provide a step-by-step guide for users.
Steps are identified and the action or concept for that step is then explained.

See Interpreting Indicators of Rangeland Health version #3 Technical
Reference 1734-6 2000 for further information. On line version is available at:

                                                                          January 4, 2005

                   Rangeland Health Protocols for CSP

The following outlines the steps to be taken when assessing Rangeland Health
during the categorization process of the CSP sign-up.

   1. Identify rangeland ecological sites on the rangeland acres being enrolled.
   2. Identify and document rangeland ecological sites that are sensitive to
      water quality and/or soil quality concerns. Sensitive rangeland ecological
      sites may be those that border water courses, are the source of runoff
      water or receive run-on water, sites that may contribute to sediment and/or
      salt delivery into water courses, sites susceptible to compaction, very
      shallow sites, and sites with high erosion potentials.
   3. At least one Rangeland Health assessment will be conducted on all
      rangeland ecological sites that are sensitive to soil quality or water quality
   4. More than one assessment will be made on sensitive rangeland ecological
      sites if the ratings for Rangeland Health indicators are obviously different.
   5. If there are no rangeland ecological sites identified as sensitive areas on
      the unit, a representative sample of all rangeland ecological sites that
      exceed 20% of the rangeland acres enrolled will be conducted. If no
      rangeland ecological site exceeds 20%, select the three sites representing
      the greatest area.
   6. Other assessments will be made on representative rangeland ecological
      sites as deemed necessary by the NRCS employee conducting the
   7. 90% of the area of each ecological site assessed must meet the
      rangeland health attribute criteria.

The following flow charts illustrate:
       A. Tasks to complete prior to signup
       B. Process for conducting each rangeland health assessment.

                                                                       January 4, 2005

             Conservation Security Program – Rangeland
                   Rangeland Health Assessment

Tasks to complete prior to signup:

     Step1. Develop watershed
     variance description, if

     Step 2. Identify ecological
     sites in watershed

     Step 3. Ecological reference
     worksheets for each             NO
                                           Develop ecological
     ecological site available             reference worksheets


     Step 4. Evaluation matrix       NO    Develop evaluation matrix
     for each ecological site              and adapt descriptors or
     available                             utilize defaults


     Step 5. Are employees           NO    Provide training on
     adequately trained to                 Rangeland Health
     conduct assessments                   assessment

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Rangeland Health Assessment Process

                                      January 4, 2005

Step 1. Identify the Evaluation Area, Determine Soil and Ecological Site
Complete the Evaluation Sheet.

Describe the Evaluation Area – The front of the Evaluation Sheet is used to
record information on site location for the assessment and basic site
characteristic information for an evaluation area.

The evaluation area should be large enough to accurately evaluate all indicators
and be at least ½ to1 acre in size. An acre is approximately the size of a football
field without the end zones. Upon arrival at the location, the evaluator(s) should
identify the boundaries of the evaluation area and walk and observe biological
and physical characteristics on up to two acres. This enables the evaluator(s) to
become familiar with the plant species, soil surface features, and the variability of
each Ecological Site on an evaluation area.

Determine the Soil and Ecological Site - Each Ecological Site within the
evaluation area should be verified by matching the evaluation area to the
appropriate Ecological Site Description and soils. Soil surveys (which include
soil maps and other useful information) should also be consulted if the soil
information in the Ecological Site Description is inadequate to correlate soils to
the appropriate Ecological Site Description. The evaluator(s) should review the
Ecological Site Description for consistency with the soils and vegetation found on
the evaluation area.

        Actions To Take If Soil And/Or Ecological Site Information Are Not
Available - In areas where soil surveys are unavailable or inadequate, aerial
photographs, topographic maps, geologic maps, and local weather records can
often be used to help decide which Ecological Site Description from adjacent
surveyed areas is most appropriate. Where Ecological Site Descriptions are
unavailable, these resources can sometimes be used to identify relevant
Ecological Site Descriptions that have been developed for similar areas in the
region. Vegetation information may be available in other sources such as habitat
type descriptions, long-term monitoring studies, and other inventory data. If
possible, enlist the service of a soil scientist to assist the evaluator(s) in making
the initial soil/site correlations.

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Step 2. Obtain or Develop the Reference Sheet (REQUIRED) and the
Corresponding Evaluation Matrix (STRONGLY RECOMMENDED)

Obtain a Reference Sheet (REQUIRED) - The Reference Sheet describes the
status of each indicator for the reference state. It serves as the primary reference
for the evaluation. The reference sheet describes a range for each indicator
based on expected spatial and temporal variability within each Ecological Site.

Reference Sheets are currently being incorporated into Ecological Site
Descriptions. If the Ecological Site Description does not include this information,
ask the person responsible for maintaining Ecological Site Descriptions in the
state (usually the NRCS state rangeland management specialist) if a draft is

If an Ecological Site Description does not exist, additional expertise will be
required to develop the Reference Sheet (see below). If expertise or time is
limited, the rangeland health evaluation should not proceed. It is not possible to
properly conduct an evaluation without a Reference Sheet. Development of the
Reference Sheet will require as much or more expertise than required to conduct
the evaluation. Memory of a similar site, professional opinion of what the site
could be, visits to reference areas, or reviews of old range or Ecological Site
Descriptions that do not contain reference sheets are not adequate substitutes
for a properly developed Reference Sheet. However, all of these information
sources can be used in the development of the Reference Sheet.

Instructions for Reference Sheet Development
Before beginning development, be sure to check with the NRCS State
Rangeland Specialist to find out if a final or draft Reference Sheet is available. If
no Reference Sheet exists, develop one using the following protocol and send it
to the NRCS state rangeland management specialist. If a draft is available, but
has not been finalized, you may use it and provide comments or suggest
modifications to the NRCS state rangeland management specialist.

1. Assemble a diverse group of experts with extensive knowledge of the
Ecological Site.
Individuals should be included who have long-term knowledge of the variability
and dynamics of the Ecological Site, in addition to rangeland professionals who
understand general soil-climate-vegetation relationships.

2. Provide this group of experts with all available sources of information.
This information should include relevant scientific literature and data from
potential reference areas, including data used to support the Ecological Site

3. Define the functional/structural groups for the Ecological Site.

                                                                         January 4, 2005

Use the Functional/Structural Groups sheet to define the functional/structural
groups and the species associated with each group. This sheet is used to group
species into life form/functional/structural categories, to determine the potential
dominance rating expected among these groups within the reference state, and
to aid in the rating of Indicator 12, Functional/Structural Groups. It is important to
have a good understanding of the characteristics that may define functional
groups. These characteristics include, but are not limited to, lifeform (tree, shrub,
sub-shrub, grass, forb, moss, lichen, cyanobacteria, etc.), nitrogen fixation
potential, rooting depth, morphology, photosynthetic pathways (warm vs. cool
season plants), and whether or not the plants are native to the Ecological Site.

The dominance rating for each functional/structural group included in the
Reference Sheet is based on a description of dominant or subdominant based on
percent composition. Each Functional/Structural Group should be identified on
the reference sheet as dominant, subdominant or other for indicator 12.

4. Visit one or more ecological reference areas (optional)

A visit to one or more potential ecological reference areas can be a useful source
of additional information for the Reference Sheet. It can also be used by
evaluators to improve their ability to recognize the indicators in the field and to
“field check” the descriptors developed in the office.

An ecological reference area (ERA) is a landscape unit in which ecological
processes are functioning within a normal range of variability and the plant
communities have adequate resistance to and resiliency from most disturbances.
An ERA is the visual representation of the characteristics and variability of the
components found in the Ecological Site Description. These areas do not need
to be pristine, historically unused lands (e.g., climax plant communities or relict

5. Describe the status of each indicator in the reference state (Corresponds to
the None-to-Slight departure from the expected for the site in the
Evaluation Matrix ).

Where possible, these descriptors should be quantitative, include expected
ranges based on natural disturbance regimes, weather, and spatial variability for
the plant communities included in the reference state for the Ecological Site.
Ecological sites include a range of soils with similar, but not identical,
characteristics. In many cases, the effects of within-site variability in factors such
as soil texture, depth, aspect, slope and shape of slope on the indicator must be
described. For example, concave areas within an Ecological Site are more likely
to receive run-on water and therefore production potential is higher. Where
available, data or other information used to support the descriptor should be cited
(e.g., from the Ecological Site Description).

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6. Weight how reliable or important each indicator is for the ecological site. The
default weight for each indicator is 1.0. Each indicator can be weighted as .5, 1.0
or 2.0 based on how reliably the indicator can be assessed, how strong the
correlation with the attribute is and how important it is for the ecological site. No
more than 50% (8) of the indicators can be assigned a weight other than 1.0.
Normally treat most indicators equally. To assign a rating to an indicator, rate up
or down only if there is strong evidence to support.

Low weight (0.5) if:
(1) low ability to assess indicator (high uncertainty)
(2) low correlation with attribute
(3) not important for the ecological site

High weight (2.0) if:
(1) highly correlated with a relatively irreversible change (presence of highly
invasive species)
(2) high correlation with attribute or sensitive to change in the attribute
(3) very important for the ecological site

As with the reference sheet itself, these weights are specific to the Ecological

Obtain the Evaluation Matrix for the Ecological Site (STRONGLY
RECOMMENDED) – The Evaluation Matrix includes detailed descriptions for
each of the five departure categories for each indicator.

The Evaluation Matrix includes five descriptors for each indicator which reflect
the range of departure from what is expected for the site: None to Slight, Slight to
Moderate, Moderate, Moderate to Extreme, and Extreme. The descriptor for
“None to Slight” comes directly from the Reference Sheet and reflects the
range of variation of the indicator in the reference state. The descriptors for the
other four classes are derived from the Reference Sheet and the generic
descriptors included in the Evaluation Matrix.

This Evaluation Matrix should be used for subsequent evaluations on the same
Ecological Site and any changes should be forwarded to the person responsible
for maintaining Ecological Site Descriptions in the state (usually the NRCS state
rangeland management specialist). This will ensure that these modifications will
be considered in ongoing revisions of Ecological Site Descriptions.

                                                                        January 4, 2005

Step 3. Collect Supplementary Information (STRONGLY RECOMMENDED)

Supplementary information is collected to improve the evaluators’ ability to make
an accurate evaluation. There are four general types of supplementary
information: (1) spatial and temporal variability, including factors affecting the
variability, (2) information from relevant Ecological Reference Areas, (3)
Functional/structural groups, and (4) quantitative cover and composition data for
the evaluation site.

Spatial and temporal variability
The Reference Sheet and Evaluation Matrix describe the range of variability
expected to occur in an Ecological Site. There is significant spatial variability in
site potential within Ecological Sites depending on soils, slope, aspect, and
landscape position. For example, for an Ecological Site that includes slopes
ranging from 5-15%, water flow patterns are expected to be more pronounced on
steeper slopes. Documenting these relatively static properties on the first page of
the Evaluation Sheet can help increase the accuracy of the evaluation.

Temporal variability is even greater than spatial variability in most Ecological
Sites. The season, time since the last storm or fire, and recent precipitation are
just a few of the factors that can affect current site potential. These factors can
also be documented on the Evaluation Sheet and used to increase evaluation

Ecological Reference Areas
Ecological Reference Areas, where available, can help by providing a visual
representation of the expected status of each indicator at the time of the
evaluation. Quantitative data can also be used to supplement the information in
the Reference Sheet. Ecological Reference Areas should be functioning at least
as well as described in the Reference Sheet with respect to soil and site stability,
hydrologic function, and biotic integrity.

Functional/Structural Groups Sheet
The Functional/Structural Groups Sheet can be used to directly compare
potential and actual relative dominance of the functional/structural groups.

Quantitative data
Quantitative vegetation and soil data can be used to support the indicator

                                                                         January 4, 2005

Step 4. Rate the 17 Indicators on the Evaluation Sheet (REQUIRED)

Complete the Evaluation Sheet, using the Evaluation Matrix.

The evaluator(s) selects the category descriptor (i.e., narrative) on the Evaluation
Matrix that most closely describes each indicator and records it on the Evaluation
Sheet. The rating for each indicator in the evaluation area is based on that
indicator’s degree of departure from the Reference Sheet. The Reference Sheet
reflects the range of variability expected for soils and plant communities in the
reference state.

Narrative descriptions in the Evaluation Matrix are intended to aid in the
determination of the degree of departure. The narrative descriptors for each
indicator form a relative scale from “Extreme” to “None to Slight.” Not all
indicator descriptors will match what is observed, requiring a “best fit” approach
when making ratings. The rating for each indicator should be supported by
comments, in the space provided by each indicator rating. In some instances
there may be no evidence of the indicator on the evaluation area. Those
indicators are rated “None to Slight.”

When making an assessment, the history of disturbances (e.g., drought, fire)
should be considered. For example, if a fire occurred 5 years ago in the area
being assessed, reduced shrub (e.g., sagebrush) cover is not necessarily an
indication of lack of biotic integrity if natural processes alone are sufficient to
allow recovery of the original plant community. Both the pre- and post-fire plant
communities are in the same state. Comments on wildfire return intervals
(expected and current) must be documented in the comments section on this

Additional information on many of the soil-related indicators can be found in the
Rangeland Soil Quality Information Sheets (NRCS Soil Quality Institute et
al.2002; http://soils.usda.gov/sqi/soil_quality/land_management/range.html).

See Interpreting Indicators of Rangeland Health version #3 Technical Reference
1734-6 2000 for description and definitions of the seventeen indicators. On line
version is available at:

The description of the indicators is also available in the National Range and
Pasture Handbook:

                                                                         January 4, 2005

Step 5. Determining the Functional Status of the Three Rangeland Health
Attributes (REQUIRED)
Complete the Evaluation Sheet

To determine the ratings for each of the attributes, convert indicator "rating" to
"value". None to Slight rating is a value of 1, Slight to Moderate rating is a value
of 2, Moderate rating is a value of 3, Moderate to Extreme rating is a value of 4
and Extreme rating is a value of 5.

Copy indicator weights for each indicator from Reference Sheet (default=1.0).
Multiple Value x Weight and write in VxW column of the Evaluation Worksheet.
Sum "Wt" and "VxW" columns for each attribute. Attribute rating equals
Sum(VxW)/Sum(Wt). The attribute ratings will range between 1 and 5. Below is
the conversion to departure from reference state for the attributes:
Numeric Rating      Departure from Reference State
1.0 – 1.5           None to Slight
1.51 – 2.5          Slight to Moderate
2.51 – 3.5          Moderate
3.51 – 4.5          Moderate to Extreme
4.51 – 5.0          Extreme

Each sensitive and predominant site is given an acreage value. A weighted
value is determined for each site based on the percent of total that site occupies.
The weighted value is multiplied times each attribute rating value. The total
weighted values within each attribute and all ecological sites are summed up.
The resulting health assessments will now represent the overall average for each
separate attribute and all sensitive and predominant acres.

When assigning the attribute rating, 90% of the area of the each ecological sites
assessed must meet these criteria.

                                                                        January 4, 2005

Adjustment and variances to be allowed:

There are times when the Rangeland Health assessment ratings are the limiting
factor in enrollment category placement on a watershed basis. When properly
applied rangeland management would not provide a significant vegetative
response within ten years to increase the Rangeland Health assessment ratings,
the follow procedures will be followed:

   1) Define and describe the rangeland degradation as it occurs throughout
      the watershed.
   2) Identify appropriate management strategies that could be applied to
      address the watersheds rangeland degradation.
   3) Landowner must show that the rating is related to resource degradation
      that occurred over 10 years ago.
   4) Landowner must show that the cause of the degradation has been
   5) Landowner must show that the results of the degradation have been
      recognized and actively addressed for the last 10 years. (Note:
      Stewardship Practices and Activities section of the enrollment category
      matrix requires two years).
   6) If the above requirements are met, rangeland health rating of 1 attribute
      can be raised by one rating class (i.e., Biotic Integrity attribute rating
      raised from Moderate to a rating of Slight to Moderate).

      Example situations:

      Situation 1
      Throughout the watershed, fire has been suppressed for 150
      years. This cultural norm has caused an increase of woody
      plants, especially juniper to increase and invade rangelands
      throughout the watershed. The state specialist and the FO
      personnel in the watershed, identify juniper encroachment as a
      resource degradation that has occurred more than 10 years
      ago, and one that is impossible for grazing management alone
      to fully address. Management strategies that are acceptable
      must show progress toward reducing juniper and other woody
      plants, and landowner must show a plan that provides for
      steady, continuous progress.

      Situation 2
      The encroachment of a noxious weed into mixed grass prairie.
      Invasive noxious weeds such as leafy spurge, once established
      in disturbed areas, can and do encroach on relatively
      undisturbed rangeland. Management strategies must include
      grazing management that favors perennial grass production
      while inhibiting the weed production, and landowner must show
      progress in treating the weeds with chemical, mechanical

                                                                      January 4, 2005

and\or biological means in an organized, planned manner that
shows steady improvement.

Situation 3
The downcutting of a major water course occurred at the turn of
the twentieth century from some known event. This
downcutting has progressed up the watershed and now is
causing active water erosion in the upland of the watershed.
Management strategies must favor increasing ground cover
and maintaining healthy root structures.

Example Scenario:

A.     Rangeland Health assessment shows None to Slight
       rating for Soil/Site Stability and Hydrologic Function and
       Slight to Moderate rating for Biotic Integrity.

B.     Landowner documents that brush encroachment is the
       cause of the Rangeland Health rating, that it occurred
       prior to 10 years ago and that Brush Management is
       designed to address the concern and has been applied
       for 10 years. Designated NRCS staff concurs as
       meeting the conditions of variance and rating of Biotic
       Integrity attribute is raised from Slight to Moderate to a
       rating of None to Slight.

                                                                    January 4, 2005

Examples of Variance Descriptions

Example 1
Statement of Prior Condition
The rangelands in this watershed were first settled in the mid 1800s. Large
unmanaged herds of sheep, horses, and cattle overgrazed many of the non-
aspect, riparian, and the accessible portions of aspect (north and south)
ecological sites in the watershed in the following 50-100 years.

These abuses have permanently changed the makeup and quality of the
characteristic historic climax plant community that would be expected on each
site. The generalized state and transition
model (below) shows common
disturbance states that have crossed
thresholds (one or more ecological
processes have been irreversibly
changed). Disturbance states 1 and 2
have lost important native perennial
grasses and biotic crusts. Disturbance
state 3 has crossed an additional
threshold where more native plants (if not
all) are lost and the site is overcome with
annual grasses and woody vegetation.
Partial or complete loss of soil surface is
often a characteristic of disturbance state

In all of these disturbance states, properly applied rangeland management will
not provide a significant vegetative response within at least ten years. There is
often little change in the plant communities after even a generation of proper

In these cases, rangeland health assessment ratings will unfairly limit enrollment
category placement to the lowest levels. This variance allows adjustments to
rangeland enrollment categories.

Criteria for Application of Variance
The offered rangeland acres must have been under a high level of grazing
management for the past 10 years. A rotational grazing system must have been
applied and a safe level of forage harvest has been practiced (livestock demand
is in balance with annual production at maximum harvest efficiency of 25%).
Each management unit receives at least 30 days of non-use during each year’s
growing season (approximately April through October). The plant communities
must be managed to supply adequate soil surface protection (litter, plant cover,
structure, etc.) to minimize erosion and maximize infiltration rates. All practical

                                                                       January 4, 2005

and feasible facilitating and accelerating practices have been implemented to
enhance grazing management.

The applicant must show that:
       The rangeland health assessment rating is related to resource
          degradation that occurred over 10 years ago,
       The cause of the degradation has been eliminated, and
       The results of the degradation have been recognized and actively
          addressed for the last 10 years according to the criteria, above.

The designated NRCS staff must concur with the use of this variance on a case-
by-cases basis. Documentation supporting the high level of grazing
management and application of other rangeland management practices will be

Example 2.
Statement of Prior Condition
                           Variance for Rangeland Health – Hondo Watershed – Texas
The rangeland in this watershed historically were grazed with all classes of
livestock at a stocking rate that exceeded carrying capacity. The climate of this
area is semi-arid in nature and subject to periodic drought. The watershed also
experiences extreme high temperatures during the growing season making
seedling plant establishment more difficult.

Past abuses coupled with drought have eliminated most climax tall and mid
grasses from the ecosystem. The loss of these fine fuels led to the removal of
fire from the rangelands. This resulted in an increase of native brush species.
Juniper is one such plant that has increased on this watershed because of the
removal fire from the ecosystem. Mixed brush species have also made a marked
increase for the same reason.

In addition, the shallow soils have lost many tons of topsoil. In certain instances
this erosion has reduced the resilience of the plant communities to respond to a
high quality range management plan.

Criteria for Application of Variance
The ranch in question must have been under a high level of management for at
least the past 10 years. During this time a rotational grazing system must have
been used to manage grazing. All pastures in the grazing system receive at
least 60 days of periodic deferment each year during the spring and/or fall
growing periods. The cooperator must have been diligent in balancing livestock
numbers with forage production. Only once in the past 10 years can grazing use
have exceeded 50% utilization of the current year’s growth of usable forage.
Stocking at a rate 20% less than carrying capacity for the past 10 years will be a
key indicator the producer was serious about making range improvement.

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Brush management is being applied in a systematic manner on the ranch for the
last 10 years. Prescribed burning and/or additional follow-up brush management
is applied to manage reinfestation of noxious brush species.

The designated NRCS staff person must concur with the use of this variance on
a case-by-case basis. Documentation supporting the high level of grazing
management and application of other range management practices will be

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