Flower availability drives effects of wildflower strips on ground-dwelling natural enemies and crop yield

Wildflower strips have been heralded as a promising way to enhance ecosystem services by providing organisms which may help make farming less dependent on external inputs. However, recent studies show inconsistent effects delivery of and crop yield, warranting more detailed analysis the factors determining wildflower strips. We examined how natural enemy groups spider, carabid beetle staphylinid beetle, well aphid pest yield respond furthermore determined whether response enemies, aphids depends flower cover species richness, this is influenced fertilizer insecticide applications in 16 winter wheat fields Netherlands. used an experimental approach with nested design that included all combinations (present/absent), application (yes/no) (yes/no). Presence did not affect ground-dwelling or yield. availability across control margins was positively related abundance pooled number spiders beetles. Positive were observed over limited distances; up 5 m from edge for The on-field management practices interact suggesting that, our study, flowers but mainly additive. Our study indicates richness wildflowers field margin habitat, rather than establishment per se, drove increases enemies This suggests attention should be given optimization success seed mixtures enhancing diversity. Furthermore, biodiversity herbaceous vegetation linear landscape elements represent cost-effective alternative boost regulating production agricultural landscapes.