Wild bee pollinators foraging in peanut and cotton adjacent to native wildflower strips

Wild bees are major contributors to pollination of economically important crops. However, widespread habitat conversion to agriculture and pesticide exposure are associated with declines in wild bee abundance and biodiversity. A growing number of studies have investigated the incorporation of a variety of flower species in agroecosystems to augment resource and habitat availability to wild bees and pollination of nearby crops. Here we investigated if wildflower strips containing Gaillardia pulchella Foug. (Asteraceae) in 2018 and G. pulchella, Rudbeckia hirta L. (Asteraceae), and Monarda citriodora Cerv. ex Lag. (Lamiaceae) in 2019 could promote pollinator abundance and pollination of nearby peanut and cotton. We used bee bowls in crop fields to capture bees and identified the pollen on the bees. We captured a total of 291 bees in peanut and 89 bees in cotton that were comprised of 2 families (Apidae and Halictidae) with 10 species represented from these families. The species in peanut were comprised mostly of Melissodes communis Cresson and Melissodes bimaculatus Lepeletier (Apidae). The bee species in cotton was comprised of mostly Lasioglossum reticulatum Robertson (Halictidae), M. communis, and M. bimaculatus. At peak abundance in peanut, 48% of bees bore both G. pulchella and peanut pollen. At peak abundance in cotton, 37% of bees bore 1 or more wildflower strip pollen and cotton pollen. Throughout the season, 62% of the bees captured in cotton had unidentified pollen from surrounding sources. These results indicate that the wildflower buffers had provided pollinators and bee foragers to these crops in early season. By studying bee foraging between crop fields and wildflower strips based on identification of pollen grain on bee bodies, we showed the potential to increase pollination in crop fields through the provision of floral resources throughout the growing season.

Automated summary

The study found that wildflower strips containing a variety of flower species could increase pollinator abundance and promote pollination of nearby crops. The wildflower buffers provided pollinators and bee foragers to crops in the early season, indicating the potential to increase pollination in crop fields throughout the growing season.