The hornet’s nest is a complex, self-contained structure built by social wasps in the genus Vespa and related species like the bald-faced hornet (Dolichovespula maculata). The primary purpose of this insect architecture is to serve as a protected nursery for the colony’s developing young, offering insulation against the elements and defense against predators. The nest is initiated by a single queen in the spring and is continuously expanded by worker hornets throughout the warm months. This temporary, single-season shelter is the central hub for all colony life, allowing the queen to focus on egg-laying while workers manage construction, foraging, and brood care.
The Outer Envelope and Construction Material
The exterior of a hornet’s nest is defined by its multilayered outer shell, often appearing as a large, grayish or tan, football-shaped structure hanging from a tree branch or tucked into a cavity. This paper-like material is a bio-composite created when worker hornets scrape and chew wood fibers from sources like dead trees, fences, or weathered lumber. The chewed wood pulp is then mixed with hornet saliva, forming a fast-drying paste that is applied in thin, overlapping strips. The resulting envelope is a brittle, laminated paper with a texture that is rough to the touch.
The color of the nest often shows subtle variations, appearing streaked with different shades of gray, tan, or brown, which reflects the different sources of wood used by individual hornets. This protective envelope is composed of multiple air-filled layers that provide insulation, helping to regulate the internal temperature and humidity for the developing brood. A single entrance hole, typically near the bottom, serves as the only access point, allowing hornets to fly in and out while keeping the interior secure.
The Tiered Internal Structure
Once the papery outer shell is breached, the interior reveals an organized, geometric arrangement of stacked combs. These internal brood combs are positioned horizontally, forming distinct, flat tiers separated by a noticeable air space. The combs are not attached directly to the outer envelope but are suspended and supported by strong, vertical pillars made of the same paper material, often called pedicels or petioles.
These supporting columns anchor the individual combs to the ceiling of the nest and to one another, creating a stable, multi-story structure. Each comb is composed of hundreds of tightly packed, hexagonal cells, all of which open downward. This downward orientation is a design feature that prevents debris and waste from accumulating in the cells and may help developing larvae adhere to the cell walls. The tiered arrangement allows the colony to maximize the number of brood cells within the enclosed space and facilitates movement of workers between levels.
Contents: The Brood Cells and Nursery
The hexagonal cells within the combs function as the individual cradles for the next generation of hornets. A single egg, which is tiny and white, is fixed to the base of each cell by the queen. After hatching, the larva progresses through several developmental stages as a legless, grub-like creature. These growing larvae are entirely dependent on the worker hornets, which feed them a protein-rich diet of chewed insects like flies and caterpillars.
When a larva is fully grown, it enters the pupal stage, undergoing metamorphosis inside its cell. At this point, the larva spins a silk cap over the cell opening, creating a sealed chamber for its transformation. The presence of capped cells indicates pupae developing into adult hornets, while open cells may contain eggs, larvae, or may be empty, awaiting a new egg. The adults eventually chew their way out of the silk cap to join the colony, where they immediately begin their work contributing to the nest’s upkeep and growth.