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Rangeland Health Assessment for 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 (STRONGLY RECOMMENDED) 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 1 Introduction 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: ftp://ftp-fc.sc.egov.usda.gov/GLTI/technical/publications/range-health-indicate.pdf January 4, 2005 2 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 concerns. 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 assessments. 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 3 Conservation Security Program – Rangeland Rangeland Health Assessment Tasks to complete prior to signup: Step1. Develop watershed variance description, if needed Step 2. Identify ecological sites in watershed Step 3. Ecological reference worksheets for each NO Develop ecological ecological site available reference worksheets YES Step 4. Evaluation matrix NO Develop evaluation matrix for each ecological site and adapt descriptors or available utilize defaults YES Step 5. Are employees NO Provide training on adequately trained to Rangeland Health conduct assessments assessment January 4, 2005 4 Rangeland Health Assessment Process January 4, 2005 5 Step 1. Identify the Evaluation Area, Determine Soil and Ecological Site (REQUIRED) 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. January 4, 2005 6 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 available. 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 Descriptions. 3. Define the functional/structural groups for the Ecological Site. January 4, 2005 7 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 areas). 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). January 4, 2005 8 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 Site. 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 9 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 accuracy. 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 evaluation. January 4, 2005 10 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 sheet. 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: ftp://ftp-fc.sc.egov.usda.gov/GLTI/technical/publications/range-health-indicate.pdf The description of the indicators is also available in the National Range and Pasture Handbook: ftp://ftp-fc.sc.egov.usda.gov/GLTI/technical/publications/nrph/nrph-ch4.pdf January 4, 2005 11 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 12 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 eliminated. 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 13 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 14 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 3. 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 management. 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 15 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 required. 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. January 4, 2005 16 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 required. January 4, 2005
"Rangeland Health Assessment"