Walnuts are an economically important forest tree used for timber and nut production, the of fruits is rich in various nutrients, becoming one four nuts world. have deep roots, which can be colonized by either ectomycorrhizal fungi or arbuscular mycorrhizal soil. These form beneficial symbioses roots walnut. A large number been identified, whilst Boletus edulis, Calvatia uiacina, Cantharelles c...