Abstract
Trees account for a quarter of the ≈ 400 000 vascular plant species and are among the largest and longest-lived organisms on Earth, growing up to 114 m tall and living in excess of 4000 years (Schulman 1958, Raven and Crane 2007). Since early in human evolution, trees have provided habitat, food, fuel, fibres and building materials. In the past 2000 years, lower-impact uses of trees and forests have given way to large-scale replacement of forests with agricultural landscapes. Forests and tree plantations are increasingly considered for their central role as providers of habitat and regulators of global biogeochemical, temperature and water cycles. This special issue draws together knowledge of nutrient relations of trees, forests and plantations.