Biodiversity and Biotic Risk Management in Plantation Forests

Meta-analyses show that pure stands of forest trees experience on average 30% more damage by insect pests than mixed-species plantations. Two main ecological mechanisms explain this associational resistance: non-host trees dilute and mask the cues that pests use to locate hosts, and diverse stands provide food and shelter for natural enemies that control herbivore populations. Resistance is stronger against specialist pests and increases with functional or phylogenetic differences among species. These findings support the design of multispecies plantations to sustainably deliver forest goods and services.