Sand bees are common ground-nesting insects that often spark concern when they appear in lawns or gardens. These are solitary species, unlike social bees such as honeybees, and use the ground for their life cycle. Only the females possess a stinger, and they are extremely unlikely to use it.
Identifying Sand Bees and Their Habitat
The common term “sand bee” typically refers to solitary species that nest in the soil, primarily belonging to the families Andrenidae (Mining Bees, Andrena species) and Colletidae (Plasterer or Cellophane Bees, Colletes species). These are medium-sized bees, generally ranging from 7 to 18 millimeters in length, and often appear fuzzy with bands of pale hair on their bodies.
Sand bees are master excavators, with each female digging her own individual vertical burrow in the ground. They prefer sites with bare, well-drained, and often sandy soil that receives morning sun exposure. The entrance to the nest is usually marked by a small, volcano-shaped mound of excavated dirt, similar to a small anthill but with a larger opening.
Although solitary, sand bees frequently nest in close proximity, forming large aggregations. This clustered nesting can give the false impression of a large, aggressive colony, but each burrow is the independent home of a single female raising her young. Their activity is usually concentrated in the early spring for a few weeks before the adults complete their life cycle and the next generation develops underground.
Understanding Their Stinging Behavior
Female sand bees are physically capable of stinging, but this is an absolute last resort, making them docile insects. Unlike social insects, such as yellow jackets, solitary sand bees have no complex hive to defend. A female’s survival is paramount, as she alone provisions her nest with pollen and nectar for her offspring.
This solitary life cycle means they are primarily focused on foraging and nest construction, and generally ignore humans and pets walking nearby. Stinging occurs almost exclusively when a female is physically trapped, such as if she is accidentally stepped on with a bare foot, squashed against the skin, or roughly handled.
Male sand bees, which are often seen actively flying low over the nesting area looking for mates, do not possess a stinger at all and are completely harmless.
Assessing the Sting Pain and Prevention
If a sand bee sting occurs, the experience is typically mild, causing only minor, localized irritation. The pain is often described as a brief pinprick sensation. Entomologist Justin O. Schmidt, who created a widely recognized pain index for insect stings, rated the sting of similar small, ground-dwelling bees at a Level 1.0, the lowest rating on his 4-point scale.
This minimal pain level is due to the small amount and weak nature of the venom compared to that of social bees or wasps. For prevention, the most effective strategy is simply to avoid disturbing the nesting sites during the few weeks the bees are active in spring.
Avoid walking barefoot in areas of bare or sparse soil where you see the small dirt mounds, and do not place hands or gardening tools directly into a burrow opening. If a sting does occur, the recommended immediate first aid is to gently scrape the stinger out with a fingernail or a blunt edge to avoid squeezing more venom into the skin. Washing the area with soap and water, followed by applying a cold compress or ice pack, will help reduce any minor swelling and provide comfort.