Higher Apoidea activity on centipedegrass lawns than on dicotyledonous plants

The role of pollen from wind-pollinated plants as a food source for pollinators is often overlooked. Bees were observed foraging pollen in lawns from centipedegrass ( Eremochloa ophiuroides [Munro] Hack.; Poaceae). However, it remains unclear whether bees also forage on the flowers of dicotyledonous plants when centipedegrass lawns are in full bloom. Therefore, the objective of this study was to determine the foraging behavior of bees when both flowering centipedegrass and dicotyledonous plants are available simultaneously. In 2023, containers of flowering goldenrod ( Solidago canadensis L.; Asteraceae), butterfly bush ( Buddleja davidii Franch.; Scrophulariaceae), and lavender ( Lavandula angustifolia Mill.; Lamiaceae) were placed on flowering centipedegrass lawns that were producing pollen. Observations revealed that foraging bees visited only the centipedegrass spikes and did not visit the flowers of dicotyledonous plants. In 2024, containers of butterfly bush and coneflower ( Echinacea purpurea [L.] Moench; Asteraceae) were positioned on centipedegrass 1–3 d after mowing. Twelve days post-mowing, foraging bees were collected from both centipedegrass spikes and dicotyledonous plant flowers. Results indicated that a significantly greater number of bees were collected from centipedegrass spikes compared to the flowers of dicotyledonous plants. The bee species collected from centipedegrass were Bombus impatiens Cresson (Hymenoptera: Apidae), Apis mellifera L. (Hymenoptera: Apidae), Melissodes bimaculatus Lepeletier (Hymenoptera: Apidae), and Lasioglossum spp., (Hymenoptera: Halictidae), whereas only Halictus ligatus Say (Hymenoptera: Halictidae) and Lasioglossum were found on dicotyledonous plants. This suggests that flowering centipedegrass is a valuable resource for foraging bees, even when the flowers of dicotyledonous plants are also accessible.