become active in early spring. 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.
More bees nest in the ground than anywhere else. These bees need bare patches so they can dig their nest tunnels. Unfortunately, adding mulch on top of these areas prevents bees from being able to nest there.
Ground or Digger Bees are beneficial insects that 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 excavate a nest in dry soil, and mound the loose soil around the nest entrance. She provisions the nest with pollen and nectar for her offspring.
Ground Bees are solitary bees. Each female digs and provisions her own burrow. However, 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 rarely do. These bees are not aggressive. However, they will sting in defense if threatened. Males of some species may behave aggressively around nesting areas, but they lack a sting. Sweat bees do have a somewhat startling habit of landing on people to lap up the perspiration from their skin; this behavior is, in fact, why they are called sweat bees. Should you swat at a sweat bee when it lands on you, it may sting you in self-defense.
How to Identify Ground or Digger Bee Nests:
Bumblebees also nest in underground burrows, though they typically use abandoned rodent burrows rather than excavate a new one. However, bumblebees live in social colonies. Observe the nest from a safe distance. Do you see a single bee coming and going, or multiple bees entering the nest? Social bees like bumblebees will aggressively defend their nests, so make sure you identify them before you take any action.
Yellow jackets also nest in the ground, and like bumblebees, often move into old rodent burrows.
Some solitary wasps are ground nesters, too. Make sure you know the differences between bees and wasps. Don't assume you have docile, ground type bees.
Mulch also kills bees that were developing underground in a bare patch before the mulch was added. Bees that mature to adulthood underground are unable to dig up through mulch to get free, so they basically die trying to get to the surface.
Ground or Digger Bees are beneficial insects and should be
left to do their thing.
However, if you must remove them, here are a few ideas:
. Use native plants, these will be adapted to winter temperatures and not need mulch to protect their roots in cold months.
. If you have to mulch your plants, leave some bare ground unmulched for bees to use.
. Devote an area in your yard to ground-nesting bees. The best place would be where you’ve seen bees nesting before. If you don’t have an area like this, you can create one by pulling up grass in an area that gets sun for most of the day.
. Another option is to make a soil pile in a similarly sunny area and allow bees to nest in it.
Bare patches for ground-nesting bees are becoming more difficult for them to find, so anything you can do is going to be beneficial!
How to Control These Ground Nesting Bees:
Before you decide to evict your bees, consider this.
These bees serve an important purpose as pollinators. They're not aggressive, and in most cases, you can still mow your lawn and continue your regular outdoor activities without fear of being stung. And nesting activity is limited to spring, so 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 or Digger Bees alone.
Ground and Digger Bees nest in dry soil, and avoid damp areas when choosing nest sites. The easiest and least toxic method of controlling digger bees is simply to water 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.
Pesticides are not recommended for the control of any Bees.
Attract Ground Bees and Other Pollinators
Bumble Bees Are Ground Nesters Too.
Orchard Mason Bees
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