The impact of weed management on wild bees

Flowering weedy plants are an often overlooked pollen and nectar resource for wild bees. These weedy plants may fill important resource gaps in heavily managed or disturbed ecosystems during times of the year when other flowering plants aren't available, such as before and after crop flowering in agricultural systems. We compared the wild bee abundance and diversity in corn fields under two management regimes in the early spring when other floral resources are limited. Eight total plots were sampled; four of which had a winter wheat cover crop planted for weed suppression, and the other four were left fallow after the previous year's harvest. We sampled fields for 6 weeks in the early spring, from the time temperatures were appropriate for bee activity until the termination of the cover crop for corn planting. We did not find a consistently strong correlation between total floral abundance and total bee abundance, but we did detect a significant amount of year-to-year and plot-to-plot variation in both bee and floral abundance.