Unlike woodland edges, flower strips do not act as a refuge for cabbage stem flea beetle aestivation.

Background: Semi-natural habitats are generally considered to be beneficial to natural enemies of crop pests and pollinators. However, they could also be used by pests, such as the Cabbage Stem Flea Beetle (CSFB), Psylliodes chrysocephala, a major pest of winter oilseed rape, Brassica napus. Adults emerge from pupation in late spring and move to aestivation habitats.

The hump-shaped effect of plant functional diversity on the biological control of a multi-species pest community.

Plant taxonomic and functional diversity promotes interactions at higher trophic levels, but the contribution of functional diversity effects to multitrophic interactions and ecosystem functioning remains unclear. We investigated this relationship in a factorial field experiment comparing the effect of contrasting plant communities on parasitism rates in five herbivore species. We used a mechanistic trait-matching approach between plant and parasitoids to determine the amount of nectar available and accessible to parasitoids.