Ground bees become active in early spring, and hardly sting. These bees dig nests in the ground, often in bare patches of the lawn or garden. If you find mounds of soil, similar to anthills but with larger openings, these may be ground bee nests. Watch for bees flying low over the ground and entering their burrows.
Did You Know?
Ground bees are non-aggressive, beneficial insects that rarely sting. In fact, the male bees lack a stinger entirely. Nesting season is limited to springtime. Unless you or a family member has an allergy, you can feel comfortable leaving the nest alone and letting the bees do their pollinating in peace.
What Are Ground Bees?
First and foremost, ground bees are beneficial insects which perform an important role as pollinators. Ground-nesting bees include the digger bees (family Anthoporidae), sweat bees (family Halictidae), and mining bees (family Andrenidae). Females are solitary creatures, excavating nests in dry soil. Each one will fastidiously mound the loose soil around her nest entrance, then provision her home with pollen and nectar for her offspring.
Despite their solitary nature, it's not unusual to find dozens of ground bee nests in one area if conditions are suitable for nesting. Males may fly over the burrows, patrolling for potential mates.
Do Ground Bees Sting?
Female ground bees can sting but, being non-aggressive by nature, rarely do. However, they will sting in defense if threatened. Males of some species may behave aggressively around nesting areas, but they lack a sting.
How to Identify Ground Bee Nests
Bumblebees also nest in underground burrows, though they typically use abandoned rodent burrows rather than excavate new ones. However, bumblebees live in social colonies.
Observe a bee nest from a safe distance. Do you see a single bee coming and going, or multiple bees entering the nest? Social bees such as bumblebees will aggressively defend their nests, so make sure you identify them before you take any action.
Yellowjackets also nest in the ground, and like bumblebees, often move into old rodent burrows. Some solitary wasps are ground nesters, as well. Make sure you know the differences between bees and wasps and never assume you have docile, ground bees.
How to Control Ground Bees
Before you decide to evict your ground bees, consider that these bees serve a valuable purpose as pollinators. They're not aggressive and, in most cases, you can still mow your lawn and continue regular outdoor activities without fear of being stung. Finally, nesting activity is limited to spring, so ground bees won't stay for long. Unless you have concerns for a family member with a bee venom allergy, it's usually preferable to leave ground bees alone.
Ground bees nest in dry soil, avoiding damp areas when choosing nest sites. Pesticides are not recommended for ground bee control. The easiest, least-toxic method of controlling ground bees is simply watering the area.
As soon as you see ground bee activity, start soaking the area with a full inch of water per week. This is usually enough to discourage the burrowing females and to make them relocate to drier ground. A thick layer of mulch on bare garden beds will also make ground bees think twice about nesting there.