NATURAL RESOURCES CONSERVATION SERVICE
extension.okstate.edu › programs › animal-waste-nutrient-management › site-files › docs › nrcspublication590std307.pdf
Grass plantings done under the Oklahoma NRCS Pasture and Hay Planting (512) or Range Planting (550) standards shall have a current soil analysis for plant available N, P, K and pH. ... All grass plantings done under the Oklahoma NRCS Critical Area