Tracking sucking herbivory with nitrogen isotope labelling: Lessons from an individual trait-based approach

•In mesocosms, sucking herbivory on grasses was tracked with 15N isotope labelling.•Process rates (herbivory, plant growth) were strongly linked to insect identity.•Also, process rates depended on the interacting plant and insect species.•This indicates trait matching, but common plant and insect traits explained little.