Throughout their lifetime, trees are attacked by a plethora of insect and pathogens and this attack is heterogeneous in space and time within crowns of individual trees and within tree populations. A high degree of intraspecific chemodiversity could thus be adaptive. In poplar, chemodiversity is mainly determined by the genotype and its biotic and abiotic environment. However, the chemodiversity within canopies of mature trees of different sexes has so far rarely been considered in chemical ecological studies in poplar. Therefore, the aim of our project is to investigate the chemodiversity within and between different genotypes of male and female black poplar trees and within the canopies of mature trees. Furthermore, we study the consequences of black poplar chemodiversity for insect herbivore and pathogen abundance and insect performance.