Floral Enhancement of Turfgrass Lawns for the Benefit of Bee Pollinators in Minneapolis, Minnesota

Abstract

The turfgrass lawn is a common feature of urban and suburban communities, often accounting for the largest green spaces by area in these landscapes. Flowering species within turfgrass lawns have the potential to serve as a source of forage for bee pollinators in urban and suburban areas. We intentionally introduced low-growing flowers to turfgrass lawns to promote bee diversity and reduce inputs, while maintaining the traditional aesthetics and recreational uses associated with lawns. We compared bee communities on lawns with naturally-occurring blooms of Trifolium repens to bee communities on florally enhanced lawns that contained Prunella vulgaris ssp. lanceolata and Thymus serpyllum in addition to T. repens. T. repens supported both wild bee communities and A. mellifera colonies, as 56 species of bees were observed on T. repens, with A. mellifera as the most common species observed. We found that florally enhanced lawns supported more diverse bee communities than lawns with just T. repens. Furthermore, the bee communities supported by florally enhanced lawns were significantly different from the bee communities supported by lawns containing just T. repens based on presence-absence (Jaccard’s dissimilarity index). Our research indicates that A. mellifera colonies and wild bee communities can be supported by allowing T. repens to bloom in turfgrass lawns, and that further steps to promote the conservation of bees can be taken by land managers by intentionally introducing low-growing flowers to lawns.