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Abstract. 1. Sown wildflower strips are increasingly being established in European countries within agri-environmental schemes to enhance biodiversity, especially in intensively used agricultural areas.2. The regulations vary between countries regarding the seed mixture, intensity of management and period of time over which subsidies are given. Insects in particular are intended to benefit from these schemes.3. This review treats studies of insect diversity and abundance in sown wildflower strips. Schemes on wildflower strips in several countries in Central and Northern Europe are compared.4. In a significant majority of studies, sown wildflower strips support higher insect abundances and diversity than cropped habitats. In general, numbers and diversity also tend to be higher than in other margin types such as sown grass margins and natural regeneration, but pollen-and nectar-rich flower mixtures may outperform them.5. Common species are the main beneficiaries of the establishment of wildflower strips, although some studies point out the presence of rare or declining insect species.6. Insect groups respond differently to particular characteristics of the strips. Flower abundance, seed mixture, vegetation structure, management, age and landscape have been identified as factors influencing insect abundance and diversity.7. Future work should address under-represented comparisons, such as with pollen-and nectar-rich seed mixes, and neglected groups, in particular parasitoids. Nevertheless, sown wildflower strips can already be seen as a beneficial measure to enhance insect diversity. This is especially the case, where schemes for sown strips vary within a region to favour different species groups.

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The objective of this study was to compare butterfly abundances and diversity between wildflower strips and extensively used meadows to identify which butterfly species can be supported by establishing wildflower strips. Butterflies were recorded along transects during one season in twenty-five sown wildflower strips and eleven extensively used meadows in a Swiss lowland agricultural landscape (600 ha). In total 1,669 butterflies of 25 species were observed (25 in the strips, 18 in meadows). This can be related to 38 species recorded in the region (lowland part of Kanton Fribourg) within the Swiss Biodiversity Monitoring Programme. In wildflower strips the number of butterflies per transect meter was significantly higher than in the meadows, but there was no significant difference in species richness. Butterfly communities, though, were quite different between the two habitat types. Habitat type, abundances of flowering plants and presence of forest within 50 m were identified as factors influencing butterfly species richness. Butterfly abundances were affected by habitat type and abundance of flowering plants. In wildflower strips, 65% of all flower visits by butterflies were observed on Origanum. It can be concluded that sown wildflower strips can support a substantial part of a regions species pool. This is mostly true for common species, but can apply to rare species when, for example, larval food plant requirements are met.

Multifunctionality has become a major objective of European agricultural policy. However, recent research concerning the multifunctionality of agriculture has focused on economic, production or abiotic factors and has paid less attention to biotic, landscape and social aspects. In addition, relationships in the form of trade-offs between different landscape values such as biodiversity, cultural heritage, recreation and aesthetics have been little studied. This case study of a farm in southern Sweden explores the synergies and conflicts that can arise between these landscape values when planning at the farm scale. The results demonstrated that it was not easy to integrate the considered landscape values in practice, though we are often asked for them in policy documents. From the case study, we developed some general relationships-synergies and conflicts-between biodiversity, cultural heritage, recreation and aesthetics that can occur when improving multifunctionality on farmland. We combined methods originating from the natural sciences and the design traditions of landscape architecture to analyse and develop assessments of landscape values with the aim of improving multifunctionality by integrating these values. Finally, we discuss how the design approach of landscape architects can contribute to developing multifunctional farm plans and how the design process results in farm-specific solutions.