Several species of ground-nesting bees tunnel in well-drained soil in sunny areas, often near flowering trees. Most ground bees are 3/8 to 1/2 inch long and vary in color from solid black to bright metallic hues; all have relatively “hairy” bodies (Figure 1). These important wild pollinators are not aggressive and should be left alone.
Ground bees are very busy in late spring as blooms become available, and these insects can be seen entering and leaving pencil- diameter holes in the ground (Figure 2). The entrances are often surrounded by small mounds of fine soil particles. Many of these bees live in individual tunnels where they raise their young, but over time, sizeable communities can develop where conditions are favorable and nearby flowers are abundant. They can sting if handled or stepped on, but they do not aggressively defend their nests.
These ground bees thrive in areas that meet their requirements. While insecticide applications may have some temporary effect, the factors that make the sites attractive remain unchanged. The bees do not like moist soil so using a sprinkler to keep the nesting area moist is a way of forcing them to relocate.
By Lee Townsend, Extension Entomologist