Ground-nesting bees represent a significant portion of bee diversity, with many species living solitary lives rather than forming large colonies like honeybees. Unlike the more commonly recognized social bees, these solitary insects construct individual nests in the soil. They are generally gentle and pose little threat, differing significantly from wasps in their behavior and nesting habits. Approximately 70% of the world’s 20,000 bee species nest underground.
Common Ground-Nesting Bee Species
Mining bees, belonging to the genus Andrena, are among the most frequently encountered ground-nesting bees. These bees are typically medium-sized, often appearing fuzzy, and exhibit a range of colors from dark metallic to reddish-brown, with some having noticeable hair bands on their abdomens. They are early spring active and are important pollinators of fruit trees and other flowering plants.
Digger bees, including genera such as Anthophora and Habropoda, are robustly built bees that can be identified by their rapid, darting flight patterns. Many species feature dense hair on their bodies, which can be black, brown, or even greenish-blue. They often have long tongues suited for collecting nectar from deep flowers.
Sweat bees, part of the Halictidae family, are diverse ground nesters, known for their attraction to human perspiration. These bees vary considerably in size and can be recognized by their often metallic coloration, ranging from bright greens and blues to coppery reds. Their nests are typically found in bare soil or sandy areas.
Cellophane bees (Colletes) are named for their unique ability to line their burrows with a waterproof, cellophane-like secretion. These medium-sized bees often have pale yellow or whitish bands on their abdomens and are important pollinators of various wildflowers and cultivated crops.
Characteristics of Their Burrows
Ground bee burrows typically appear as small, circular holes in the soil, about pencil-diameter. Around the entrance, a small mound of excavated dirt often accumulates, sometimes called a “tumulus” or “chimney.” These structures are created as the female bee removes soil from her tunnel.
These nests are commonly found in areas with bare or sparsely vegetated soil, particularly in sunny locations or on gently sloped ground. These spots offer optimal conditions for digging and offspring development. While many holes might be visible in an area, each opening usually signifies an individual nest constructed by a single female bee, not a communal dwelling.
Understanding Their Behavior and Role
Ground-nesting bees exhibit a solitary lifestyle, meaning each female bee constructs and provisions her own nest independently, without the cooperative efforts seen in social bee colonies. She creates individual brood cells within the burrow, provisioning each with an egg and a mixture of pollen and nectar to sustain the developing larva until it emerges as an adult.
These bees are generally docile and non-aggressive. They rarely sting, occurring only if directly threatened, such as being stepped on or squeezed. Their primary focus is on foraging and nesting, not on defending a communal hive. These bees serve as effective pollinators for a wide array of plants, including many native wildflowers, garden plants, and agricultural crops, contributing significantly to ecosystem health and food production.
Living Alongside Ground Bees
Coexisting with ground-nesting bees means understanding their harmless nature and environmental benefits. Allowing them to nest undisturbed effectively supports their populations. Their presence indicates a healthy ecosystem, and they contribute to the pollination of plants.
Educating others about their non-aggressive behavior helps alleviate fears. Avoiding the use of pesticides in areas where they nest is important, as these chemicals harm bees and disrupt their life cycle. Their nesting season is typically brief, lasting only a few weeks in the spring or summer, after which the adults complete their life cycle and the young develop underground.
Common Ground-Nesting Bee Species
Mining bees, belonging to the genus Andrena, are among the most frequently encountered ground-nesting bees. These bees are typically medium-sized, ranging from a few millimeters to the size of a small bumblebee, and appear hairy, often with pale bands of hair on their abdomens. Many species are active in early spring, making them important pollinators for early-flowering plants, including fruit trees like apples and blueberries.
Digger bees, including genera such as Anthophora and Habropoda, are robustly built bees that can be identified by their rapid, darting flight patterns. Many species feature dense hair on their bodies, which can be black, brown, or even greenish-blue, and they often have long tongues suited for collecting nectar from deep flowers. These bees often form turrets at their nest entrances and can be found in clay soils.
Sweat bees, part of the Halictidae family, are diverse ground nesters, known for their attraction to human perspiration. These bees vary considerably in size, typically ranging from 3 to 10 millimeters in length, and can be recognized by their often metallic coloration, ranging from bright greens and blues to coppery reds. Their nests are typically found in bare, well-drained soil.
Cellophane bees, or polyester bees (Colletes), are named for their unique ability to line their burrows with a waterproof, cellophane-like secretion. These medium-sized bees often have pale yellow or whitish bands on their abdomens and possess unique heart-shaped faces.
Characteristics of Their Burrows
Ground bee burrows typically appear as small, circular holes in the soil, often about the diameter of a pencil. Around the entrance, a small mound of excavated dirt, sometimes referred to as a “tumulus” or “chimney,” often accumulates. These structures are created as the female bee removes soil from her tunnel.
These nests are commonly found in areas with bare or sparsely vegetated soil, particularly in sunny locations or on gently sloped ground. Such spots offer optimal conditions for the bees to dig and for their offspring to develop. While many holes might be visible in an area, each opening usually signifies an individual nest constructed by a single female bee, not a communal dwelling.
Understanding Their Behavior and Role
Ground-nesting bees exhibit a solitary lifestyle, meaning each female bee constructs and provisions her own nest independently, without the cooperative efforts seen in social bee colonies. Her primary objective is to create individual brood cells within the burrow, where she deposits an egg and provisions it with a mixture of pollen and nectar. This food source sustains the developing larva until it pupates and emerges as an adult bee.
These bees are generally docile and exhibit a non-aggressive temperament. They rarely sting, and such an event typically occurs only if the bee feels directly threatened, such as being accidentally stepped on or squeezed. Their primary focus is on foraging and nesting, not on defending a communal hive. These bees serve as effective pollinators for a wide array of plants, including many native wildflowers, garden plants, and agricultural crops, playing a significant role in ecosystem health and food production.
Living Alongside Ground Bees
Coexisting with ground-nesting bees involves understanding their harmless nature and their benefits to the environment. Allowing them to nest undisturbed is the most effective way to support their populations. Their presence indicates a healthy ecosystem, and they contribute to the pollination of plants.
Educating others about the non-aggressive behavior of these bees can help alleviate unnecessary fears. Avoiding the use of pesticides in areas where they nest is important, as these chemicals can harm the bees and disrupt their life cycle. Their nesting season is typically brief, lasting only a few weeks in the spring or summer, after which the adults complete their life cycle and the young develop underground.