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Agricultural Statistics is published each year to meet the diverse need for a reliable reference book on agricultural production, supplies, consumption, facilities, costs, and returns.

Many soil properties have changed and can change as a result of management, historical land use, or even natural factors, such as drought, interacting with land use. National soil survey databases currently include soil property information for the relatively static soil properties, such as texture, and also for properties affected by management, such as soil organic matter. The databases do not, however, distinguish the values of dynamic soil properties (e.g., organic matter, bulk density, infiltration rate) according to their land use, management system, ecological state, or plant community. ?Dynamic soil properties? as defined in this Guide are soil properties that change within the human time scale. Differences that may exist in these properties can affect the performance of the soil. Furthermore, some dynamic soil properties change very little in response to management and disturbances.

This technical note provides general guidance on how to install and use piezometers and water-table wells to investigate soil water regimes under conditions commonly encountered in Soil Survey and hydropedology studies. Piezometers and water-table wells installed using these procedures act as lined and unlined bore holes, respectively (Soil Survey Division Staff 1993, page 93), usually at depths that desaturate seasonally. Standard guidelines (Sections 3 and 5) are presented for use in soils where hand augering is practical and saturated hydraulic conductivities are moderate or higher. Alternative methods (Section 6) are provided for problem soils where the standard procedures are impractical or problematic. Limitations: Procedures described here are appropriate only to monitor changes in water level and hydraulic head. They are not intended for water quality sampling, water supply, or determination of saturated hydraulic conductivity (Ksat).

Soil quality is the capacity of a specific kind of soil to function within natural or managed ecosystem boundaries to: ? sustain plant and animal productivity ? maintain or enhance water and air quality ? support human health and habitation Soil function describes what the soil does. Soil functions are: (1) sustaining biological activity, diversity, and productivity; (2) regulating and partitioning water and solute flow; (3) filtering and buffering, degrading, immobilizing, and detoxifying organic and inorganic materials, including industrial and municipal by-products and atmospheric deposition; (4) storing and cycling nutrients and other elements within the earth

This Guide provides assistance to Natural Resources Conservation Service (NRCS) staff and its conservation partners to collaboratively develop Soil Quality Cards with local farmers. Partners such as Soil and Water Conservation Districts (SWCD), Cooperative Extension Service, state conservation agencies, and local groups assist in producing Cards that farmers and other land managers can use to assess soil quality on their land and implement management practices that ensure long-term soil productivity. To develop a process that enables NRCS and its conservation partners to design locally adapted Soil Quality Cards, the Soil Quality Institute worked with several university extension and research departments and enlisted the expertise of NRCS state and field staff across the country. The outcome is a participatory process through which farmers and conservationists learn together about soil quality and collaboratively develop assessment tools customized to local needs.

This publication, Keys to Soil Taxonomy, Twelfth Edition, 2014, coincides with the 20th World Congress of Soil Science, to be held on Jeju Island, Korea in June 2014. The Keys to Soil Taxonomy serves two purposes. It provides the taxonomic keys necessary for the classification of soils in a form that can be used easily in the field. It also acquaints users of soil taxonomy with recent changes in the classification system. The twelfth edition of the Keys to Soil Taxonomy incorporates all changes approved since the publication in 1999 of the second edition of Soil Taxonomy: A Basic System of Soil Classification for Making and Interpreting Soil Surveys. The authors of the Keys to Soil Taxonomy are identified as the ?Soil Survey Staff.? This term is meant to include all of the soil classifiers in the National Cooperative Soil Survey program and in the international community who have made significant contributions to the improvement of the taxonomic system.

This technical guide, originally published in 2007, provides guidance for implementing the U.S. Department of Agriculture (USDA) Forest Service national ground water policy. It describes hydrological, geological, and ecological concepts, as well as the managerial responsibilities that must be considered to ensure the wise and sustainable use of ground water resources on NFS lands. 64 figures. 11 tables.