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Web Soil Survey Annual Data Refresh

Web Soil Survey infographic.The entire official soil survey database was refreshed October 31, 2017. The updated official data is now available for use in implementing national programs affecting landowners and managers. Interpretation criteria will be posted as updates are completed for many national interpretations.

Four new national interpretations have been added this year:

► “Farm and Garden Composting Facility – Surface”:  Composting facilities are designed to provide six critical factors in relative proportions so that the process of biological degradation is sustained. Deficits in any of the critical factors, or imbalances among them, may result in extremely slow composting, or a dormant composting system. Mixing of materials also redistributes heat, air, and water and will speed the process of biological degradation. Large facilities may provide mechanical mixing of the compost materials. Smaller facilities may rely on manual turning of the materials, or may add some materials that are too large to compost in order to create channels for air flow through the pile.

“Fragile Soil Index”:  Fragile soils are those that are most vulnerable to degradation. They are easily degraded (have low resistance) and are highly susceptible to erosion with low resilience. They are characterized as having low organic matter contents, low water-stable aggregates, and low soil structure. Fragile soils are generally located on sloping ground, have sparse plant cover, and tend to be in arid and semiarid regions. A fragile soil index interpretation was developed to rate soils based on their fragility. The index can be used in conservation and watershed planning to assist in identifying soils and areas with greater vulnerability to degradation.

National Crop Index infographic.► “NCCPI – National Commodity Crop Productivity Index (version 3.0)”:  This NCCPI interpretation replaces version 2. The NCCPI is a method of arraying the soils of the United States for non-irrigated commodity crop production based on their inherent soil properties. This interpretation is applicable to both heavily populated and sparsely populated areas in their present condition. The present land use is not considered in the ratings.

► “Soil Susceptibility to Compaction”:  This interpretation is designed to predict the susceptibility of soils to compaction from operation of ground-based equipment for harvesting and site preparation activities when soils are moist. Soil compaction reduces porosity and increases bulk density by reducing the interaggregate pore space. Compacted soils are less favorable for good plant growth because of high soil bulk density and hardness, reduced pore space, and poor aeration and drainage. Root penetration and growth is decreased in compacted soils because the hardness or strength of these soils prevents the expansion of roots. Supplies of air, water, and nutrients that roots need are also less favorable when compaction decreases soil porosity and drainage.

Individuals interested in knowing when surveys in a particular state are updated should visit the Web Soil Survey, click on the “Download Soils Data” tab, then choose the State they are interested in. WSS will display a list of all soil survey areas. Individuals interested in soil related issues may subscribe to topics of interest using a free subscription service through GovDelivery offsite link image    . Individuals can email inquiries to for assistance with GovDelivery and WSS.

Customers may click on the “Contact Us” link in WSS to receive assistance though the Soils Hotline, a State Soil Scientist, or a local NRCS Service Center. Questions about soil data in a specific state should be directed to the State Soil Scientist. Contact information for all State Soil Scientists is available. For more information on the Web Soil Survey, see “I Want Help With…” on the Web Soil Survey Home Page.