Pollination by native bees is economically and ecologically vital to agro-ecosystems and nature. The majority of wild bee species in North America rear their offspring below ground. When residing in agro-ecosystems, physical manipulations of the soil associated with tillage in row crop systems may pose a serious threat. Tillage methods vary but are generalized as belonging to either a conventional or conservation tillage regime. Conventional tillage is associated with high intensities of soil disturbance compared to the latter; however, conservation tillage also differs by purposefully manipulating ground cover through the buildup of surface residues. Here, we investigated the effects of common tillage practices employed in the South Eastern United States on ground nesting bees by intensively sampling with soil emergence traps. The sampling took place within four treatment groups: (1) Conventional tillage, (2) Conservation tillage, (3) Reduced tillage scheme, and (4) Field Edge. Soil emergence traps were deployed weekly from spring to early fall in 2021 and 2022 for a total of 48 sampling rounds and 4,608 individual trap deployments. Results from emergence trap collections revealed that ground nesting bee incidence, abundance and diversity were comparable among all of the tilled in-field treatments, while the field edge displayed statistically higher bee incidence, abundance and diversity. Our results suggest that bee nesting is diminished in cultivated fields regardless of tillage type. The implications of these results are relevant to conservation efforts aimed at mitigating the loss of bee biodiversity, especially in landscapes dominated by agricultural activity.
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