Written by Tianna DuPont, WSU Tree Fruit Extension Specialist; David Granatstein, Professor Emeritus, WSU; Bernardita Sallato, WSU Tree Fruit Extension Specialist. Published Feb 2020.
Orchard soil health, or soil quality, is the capacity of soil to support productive trees over time without negatively affecting the surrounding environment. Soil health is influenced by interacting biological, physical, and chemical properties of soil. Active soil biological communities mineralize nitrogen, create soil structure, and compete with plant pathogens. Physical properties of soil determine its ability to store and release nutrients; accommodate water entry, storage and movement; provide sufficient oxygen for roots and microbes; and moderate environmental stress. Chemical aspects of soil health include nutrient presence and availability, pH, cation exchange capacity (CEC), salinity, and the presence of any contaminants, such as heavy metals or persistent pesticide residues. By increasing our understanding of the biological and physical as well as chemical properties of soil we may be able to increase root health, moderate nutrient and water stress, and increase the yield potential of our orchards.