Bridging the gap between scientific knowledge and practice: how can we assist organic farmers in sustaining wild bees and pollination on their farms?

Wild bees (bumblebees and solitary bees) are two important groups of wild pollinators in temperate zones, delivering pollination services to crops and wild plants. It is well documented that wild bees are declining nationally and regionally in Europe (Biesmeijer et al., 2006) threatening crop pollination estimated to 14 mia. euro/year. Wild bees are dependent on presence of high quality flower resources and on suitable nesting and overwintering sites locally (Strandberg et al., 2011). In the agricultural landscape, availability of these resources depend on land use, i.e. distribution between arable land and uncropped areas, crop distribution and management as well as quantity and quality of permanent grasslands, hedgerows, road verges, etc. Although organic farms have the potential for harboring wild plants with high flower intensity due to absence of herbicides and crop distribution (Henriksen et al., 2013), organic farms in practice vary highly in availability of food and nesting resources temporally and spatially