Bees are often misunderstood regarding their diet and interaction with wood. A common misconception is that bees consume wood, similar to termites. However, bees do not eat wood; their dietary needs are entirely different. This distinction is important for understanding their behavior and identifying potential pest issues.
Bees’ Actual Diet
Bees primarily rely on two plant-derived substances for their nutrition: nectar and pollen. Nectar, a sugary liquid from flowering plants, serves as their main source of carbohydrates, providing energy for flight and daily activities. Pollen is a crucial source of proteins, fats, vitamins, and minerals, essential for the growth and development of adult bees and their larvae.
Worker bees collect both, transporting them back to the hive. Nectar is converted into honey, serving as a stored food source for the colony. Royal jelly, a secretion from young worker bees, is fed to all larvae initially and exclusively to the queen bee throughout her development.
Why Bees Interact with Wood
The misconception that bees eat wood often stems from observing carpenter bees (genus Xylocopa) interacting with wooden structures. Unlike social bees, carpenter bees are solitary. They are commonly found near untreated wood on homes, decks, or outdoor furniture.
Their presence, marked by visible holes, can lead homeowners to mistakenly associate them with wood-destroying pests. However, these bees do not consume the wood; their interaction is solely for nesting purposes. They create tunnels within wood to lay their eggs and raise their young.
How Bees Utilize Wood for Nesting
Female carpenter bees bore into wood to create nesting galleries. They prefer soft, untreated, or weathered woods such as pine, cedar, cypress, or redwood. The process begins with the bee chewing a circular entrance hole, typically about 0.5 inches (1.27 cm) in diameter, which penetrates about 1 to 2 inches (2.5 to 5 cm) into the wood. After this initial boring, the bee turns at a right angle and excavates a tunnel that runs parallel to the wood grain, often extending 6 to 12 inches (15 to 30 cm).
These tunnels are then divided into individual cells, each provisioned with a “bee bread” mixture of pollen and nectar for the developing larvae. An egg is laid in each cell, and the cell is sealed off with wood shavings and a sticky secretion. The wood shavings produced during tunneling are pushed out of the entrance hole, often forming small piles of sawdust below the activity site; these shavings are never consumed by the bees. While a single tunnel typically causes minimal structural concern, repeated tunneling by multiple generations or the expansion of existing tunnels over several years can sometimes weaken wooden elements.
Differentiating Bees from Wood-Eating Insects
Distinguishing carpenter bees from true wood-eating pests is important for proper identification and management. Termites, unlike bees, actually consume wood. Subterranean termites often create mud tubes on surfaces as protected pathways and leave wood hollowed out from the inside, sometimes with a honeycomb-like texture. Drywood termites, common in warmer climates, produce small, pellet-shaped fecal droppings known as frass, which can be found near tiny “kick-out” holes.
Powderpost beetles are another type of wood-destroying insect that feed on wood. Their presence is indicated by very small, round exit holes, typically 1/16 to 1/8 inch (0.16 to 0.32 cm) in diameter, and fine, powdery wood dust (frass) that resembles flour, often found near the holes or on surfaces below. The larvae of these beetles tunnel through wood for months or years, weakening its integrity.
Carpenter ants, similar to carpenter bees, do not eat wood but excavate it to create nests. Their tunnels are typically smooth and clean, without sawdust or frass, as they push excavated wood out of their galleries. Carpenter ants often prefer moist or decaying wood, and their larger size and social colonies further differentiate them from solitary carpenter bees. The key difference remains that bees use wood for shelter, while termites and powderpost beetles consume it, and carpenter ants excavate it for nesting without consuming it.