In times of climate change and emerging diseases and pests, genetic diversity is crucial for keeping forests healthy. Native trees and shrubs are wild populations that originally occur in the Netherlands and have reproduced naturally from generation to generation. These wild populations cover only 3-5% of our forests and landscape elements but remain essential as the original sources of genetic diversity. Once genetic diversity is lost, it cannot be regained. The Dutch Centre for Genetic Resources (CGN), is dedicated to the conservation and sustainable use of genetic diversity.