The presence of bees around bushes and shrubs is common in gardens and wild areas. When observed near shrubbery, bees are typically seeking food from flowers or utilizing the plant’s structure for shelter and reproduction. Bushes offer a unique combination of floral resources and physical architecture, making them valuable habitats for many different bee species. Understanding these behaviors helps identify which types of bees are present and highlights the important ecological role shrubs play in supporting local pollinator populations.
Bees That Use Shrubs for Nesting and Shelter
Many native bee species are solitary, meaning they do not live in large colonies, and depend on plant structure to create individual nests. Shrubs with hollow or soft, pithy stems provide ready-made cavities that bees can easily excavate and partition into brood cells. Small Carpenter Bees (Ceratina species) use their mandibles to hollow out the spongy center, or pith, of dead canes from plants like raspberry or elderberry. These tiny bees lay an egg on a pollen ball inside the stem and seal the cell before moving on.
Other cavity-nesting bees, such as Leafcutter Bees (Megachile species), prefer existing holes but will use stems of plants like roses or thistles if the diameter is suitable. They line and cap their nest chambers with precisely cut pieces of leaves, often taken from nearby shrubs.
The dense foliage of a bush also provides excellent cover for ground-nesting species, which account for nearly 70% of all bee types. The base of a bush offers a protected area of exposed soil ideal for solitary ground-nesting bees like Mining Bees (Andrena species) and Sweat Bees (Lasioglossum species). Bumblebees (Bombus species), which nest underground, frequently utilize abandoned rodent burrows beneath dense shrubs for insulation and predator protection. The bush canopy helps stabilize the soil and buffers against heavy rain or direct sunlight, maintaining necessary conditions for the underground nursery.
Bees That Forage Heavily on Flowering Bushes
Flowering shrubs are significant sources of pollen and nectar, especially during early spring when many other plants have not yet bloomed. The early flowering of woody plants, such as willows, blueberries, and California lilac (Ceanothus), provides essential resources for queen bumblebees and other species emerging from overwintering. These high-yield blooms attract generalist foragers like Honeybees (Apis mellifera) and most species of Bumblebees, which efficiently exploit large patches of flowers.
Some foraging relationships are specialized due to unique floral characteristics. Bumblebees are frequently observed on Rhododendron and Azalea bushes, which have deep, high-nectar flowers. They are particularly suited for these flowers, sometimes employing “buzz pollination” to release pollen tightly held within the anthers.
The nectar of some Rhododendron species contains grayanotoxin, a compound that bumblebees can tolerate but which is toxic to honeybees, influencing which visitors are present. The structure of shrub flowers also determines which bees visit; for example, long-tongued bees are drawn to the tube-shaped flowers of honeysuckle. Conversely, open, bowl-shaped blossoms are easily accessed by a wider range of short-tongued bees.
Visual Characteristics for Identification
To identify common bees found in and around bushes, observers should focus on size, hairiness, and pollen-carrying method.
Bumblebees
Bumblebees are the easiest to spot, being large, round, and densely covered in black and yellow hair, giving them a fuzzy appearance. They often exhibit a slow, deliberate flight and may be seen entering or leaving the ground beneath the bush canopy.
Leafcutter Bees
Leafcutter Bees are medium-sized, often black with pale hair bands, and possess a large head and powerful jaws used for cutting leaves. A key identifying trait is their pollen-carrying method: they carry bright yellow or white pollen on stiff hairs (scopa) on the underside of their abdomen, unlike honeybees which use hind leg baskets. If a bush shows small, perfectly semicircular cuts on its leaves, a leafcutter bee is the likely culprit.
Small Carpenter Bees
Small Carpenter Bees are tiny, slender bees, typically three to ten millimeters long, with a shiny, dark, metallic blue-green or black body that is sparsely covered in hair. Their abdomen is cylindrical, and they move quickly around the small, dead stems of bushes where they excavate their nests. They carry pollen on hairs on their hind legs, and their small size often causes them to be mistaken for flies.