Flower plantings increase wild bee abundance and the pollination services provided to a pollination‐dependent crop

Abstract

Summary1. Pollination services from wild insects contribute to crop productivity around the world, but are at risk of decline in agricultural landscapes. Using highbush blueberry as a model system, we tested whether wildflower plantings established adjacent to crop fields would increase the abundance of wild pollinators during crop bloom and enhance pollination and yield. 2. Plantings were seeded in 2009 with a mix of 15 perennial wildflower species that provided season-long bloom and increased plant density and floral area during the subsequent 3 years. 3. Honeybees visiting blueberry flowers had similar abundance in enhanced and control fields in all 4 years of this study, whereas wild bee and syrphid abundance increased annually in the fields adjacent to wildflower plantings. 4. Crop pollination parameters including percentage fruit set, berry weight and mature seeds per berry were significantly greater in fields adjacent to wildflower plantings 3 and 4 years after seeding, leading to higher crop yields and with the associated revenue exceeding the cost of wildflower establishment and maintenance. 5. Synthesis and applications. We suggest that provision of forage habitat for bees adjacent to pollinator-dependent crops can conserve wild pollinators in otherwise resource-poor agricultural landscapes. Over time, these plantings can support higher crop yields and bring a return on the initial investment in wildflower seed and planting establishment, also insuring against loss of managed pollinators. Further understanding of the importance of planting size, location and landscape context will be required to effectively implement this practice to support crop pollination.

Spatial diversification of agroecosystems to enhance biological control and other regulating services: An agroecological perspective

“…Flowering habitats can support flower-visiting natural enemies on the one hand, but also pollinators on the other hand (Blaauw and Isaacs, 2014;Nicholls and Altieri, 2013) (some insect species being both natural enemies and pollinators, depending on their development stage, e.g. some species of hoverflies).…”

“…The effect of non-crop habitats on yield of adjacent crops has been measured only recently (Uyttenbroeck et al, 2016). Sowing grassy or wildflower strips adjacent to wheat (Tschumi et al, 2016a), bean (Vicia faba), oilseed rape or blueberries (Vaccinium corymbosum) (Blaauw and Isaacs, 2014) enhanced crop yield by supporting natural enemies and/or pollinators. At larger scales, assessments of landscape diversification on crop yield are also recent (Veres et al, 2013).…”

“…It showed that with limited changes in terms of farming practices, a reduction of 30 % of the pesticide Treatment Frequency Indicator will not reduce economic profits of farmers in France (Jacquet et al, 2011). Moreover, a prediction showed that the financial investment of sowing wildflower strips adjacent to blueberries was reimbursed from the fourth year after sowing without subsidies (and obviously earlier with subsidies) thanks to the pollination service provided by wild pollinators, but specified that this time frame highly depends on commodity prices (Blaauw and Isaacs, 2014). Additionally in their study, and consistently with the interviews of farmers conducted by in Belgium, wildflower strips were sown in marginal lands which highlights that non-or less productive land can be dedicated to non-crop habitats, which represents an opportunity to increase benefits by enhancing ecosystem services without the risk of losing productive lands.…”

Intersection between biodiversity conservation, agroecology, and ecosystem services

“…Thus, it is not surprising that local practices that increase diversity and abundance would also promote increased crop yields. For example, crops next to wildflower strips exhibit greater fruit set and weight, as documented for blueberry (Blaauw and Isaacs 2014), mango (Carvalheiro et al 2012), and strawberries (Feltham et al 2015). The benefits of hedgerows to crop pollination, however, may be crop-and region-specific (Sardinas and Kremen 2015).…”

Increasing Bee Forage for a Sustainable Bee Industry in Kenya

“…In the wake of dwindling Bee forage resources, suitable quick flowering plants, with adequate nectar and pollen, such as: Kales, Sunflower and Strawberry, can be introduced to farmlands, to support and sustain Beekeeping industry [1][2][3][4][5][6]. Under field conditions, bees will normally have a choice of forage sources [7].…”