In Brazil, Pinus species are grown on approximately 1.87 million hectares, usually on chemically poor soils. The present study investigated the mineralogy of sand, silt and clay fractions and estimated the mineral reserve of K by different chemical extraction methods in naturally K-poor soil under Pinus taeda L., in the State of Paraná, Brazil. In a 500 m2 area, five trees with large diameter (dominant trees) were selected, and trenches opened (depth 1.6 m) under the canopy of each tree. […]