TSSH Part 620
Rangeland Management and Rangeland Health Assessments
Soil is the most basic resource on rangeland and is the foundation for plant communities across the landscape. Soil also plays an important role in nutrient cycling and defining water resources on rangeland. Information on rangeland is provided in the National Range and Pasture Handbook. The assessment and monitoring of soils, soil quality, and other resources are used to address a wide variety of management issues and activities.
Why we assess and manage rangeland (620.01)
The Soil Conservation Act of 1935 provides the basic authority for programs of the NRCS. This act declares that it is the policy of Congress to control and prevent soil erosion and thereby preserve the natural resources on the Nation’s farmland, grazingland, and forestland. It authorizes the Natural Resources Conservation Service to carry out conservation measures on the land and to assist land users in conducting conservation activities (Public Law 46, 74th Congress).
NRCS responsibility and programs were broadened by the Watershed Protection and Flood Prevention Act, Public Law 566, 1954, as amended, and the Food and Agricultural Act of 1962, Public Law 87-703, as amended. The Farm Bill authorizes technical assistance for the Conservation for Private Grazing Lands Program (Title III, H.R. 2854, Section 386).
NRCS has specific responsibility to assist owners and operators of grazingland in planning and applying conservation programs on the privately controlled land in their operating units (Amendment No. 4, Title 9, Administrative Regulations, May 17, 1954, and Comptroller General’s Opinion B-115665 of October 1, 1953, 33CG:133).
Soil properties used for rangeland assessments (620.02)
Soil properties typically monitored/identified for rangeland assessments include: soil texture, infiltration, hydraulic conductivity, porosity, soil/slope stability, compaction, pH, hydrophobicity after fire, aggregate stability/soil crusting, salinity, alkalinity, biological activity, and soil moisture. The resource soil scientist can play a significant role in measuring and monitoring these and other soil quality parameters.
Roles of resource soil scientists in rangeland management and assessment (620.03)
Ecological Site Development and Verification. Resource soil scientists often are part of a team that develops ecological site descriptions for a given major land resource area (MLRA). Plant communities and soils typically go hand in hand; certain plant communities can be inferred from a determination of the soil type, and vice versa. The resource soil scientist needs to be familiar with the soils in a given area and should be able to identify those soil types in the field to help correlate plant communities and soils. The resource soil scientist also should be familiar with and able to identify major plants in his or her area of responsibility. The resource soil scientist has the primary responsibility to collect the dynamic soil property data associated with states of ecological sites.
Because soil surveys are not site specific and map units have inclusions, the resource soil scientist is often called upon by field office personnel to help identify the soil(s) and determine the ecological site(s).
Soil Quality / Soil Health Assessment. There are many situations in which rangeland production may be hampered by certain management practices or natural soil conditions that producers and/or range management specialists can readily see when range inventories are conducted. The resource soil scientist can be called upon to explain those conditions and should be familiar with available tools, such as the soil quality test kit, to identify and address various situations that can cause a decline in production. These situations include soil compaction in localized areas resulting from livestock concentrating in certain areas or continuous overstocking/overgrazing; saline seep development induced by improper management and/or longer term excess rainfall; soil crusting caused by decreased aggregate stability resulting from continuous overgrazing; and areas that are sodic. More information can be found on the NRCS Soil Health Assessment Web page.
Livestock Water Development. Range management specialists work with land owners to develop grazing plans that help to maximize rangeland production and maintain sustainability. Often, this process requires developing livestock watering facilities so that certain pastures can be cross fenced and put into a grazing rotation. The resource soil scientist normally is called upon to ensure site suitability for embankments or excavated ponds and thus minimize the risks of structure failures or excessive water losses caused by porous substrates or highly permeable soils. Also, the resource soil scientist may be called upon to identify whether project sites, especially spring developments, fall within the boundaries of wetlands. Various guidelines direct NRCS employees to avoid or minimize impacts to wetlands when they provide cost-share or technical assistance (National Environmental Compliance Handbook, EO 11990, and NRCS wetland policy, GM Title 190, Part 410; Subpart B—410.26, Protection of Wetlands (F) NRCS Technical Assistance Procedures).