NRCS's National and State Resource Concerns and Planning Criteria document (Appendix B, Exhibit 5-1) displays all the resource concerns that NRCS currently addresses, and wind erosion is categorized as a Soil Erosion resource concern. However, particulate emissions of dust can originate from agricultural sources other than from wind blowing across fields and pastures. In these cases, dust is recognized as an air quality problem, and can be found in the Resource Concern guide under Air Quality Impacts. Emission sources causing air quality concerns include tillage, prescribed burns, combustion engines, feed lots, unpaved traffic areas, and manure transfer. These kinds of air quality issues are typically measured/categorized as particulate matter (PM)10 and PM2.5. PM10 consist mostly of dust, pollen, and other organics such as mold spores, while PM2.5 generally concerns particulates produced by combustion sources or formed via chemical reactions of precursor gases in the atmosphere.
As noted in Exhibit 5-1, wind erosion can be screened from assessment during conservation planning activities for cropland if permanent ground cover exceeds 90%. For practicality’s sake, most perennial cropping/pasture systems are considered “permanent,” even though they may be renovated or replanted every three to five years. In essence, this means NRCS conservation planners need not spend time assessing the extent of wind erosion on these systems because the overwhelming likelihood is that a wind erosion problem does not exist. For forestland, the screening criteria is greater than 80% organic residue cover. For rangeland, each state has the prerogative to establish its own screening criteria; this is due to the variability of range conditions across the country, including vegetation types and ecological sites being grazed, canopy cover, grazing management systems, etc.