Bald-faced hornets (Dolichovespula maculata) are social wasps known for constructing large, distinctive paper nests. These insects, which are technically a type of yellowjacket, create impressive aerial structures that house their colonies throughout a single season.
The Nest Building Process
Nest construction begins in spring with a single overwintering queen. After emerging from hibernation, she selects a suitable location, often in trees, shrubs, utility poles, or under building eaves. The queen gathers wood fibers, typically from weathered or rotting wood, chewing them and mixing them with her saliva to create a paper-like pulp.
She uses this material to build a small, initial nest, roughly the size of a golf ball or tennis ball, containing a few hexagonal cells where she lays her first eggs. Once the first generation of sterile female workers emerges, they assume the primary duties of nest construction and foraging. This allows the queen to focus solely on laying more eggs, accelerating the colony’s growth. Workers continuously expand the nest, adding new layers of paper and tiers of hexagonal comb cells within a thick, layered outer shell.
Factors Influencing Nest Growth
Several elements influence the speed and ultimate size of a bald-faced hornet nest. A larger colony, with more workers, leads to faster and more extensive construction as the worker population increases. Resource availability also plays a significant role; nests require ample wood fiber and water for efficient building. Weather conditions are another determinant; warm, dry periods are ideal for rapid construction, while cold temperatures or excessive rain can slow building activity. Nest building is most rapid during late spring and summer, coinciding with peak colony expansion due to abundant resources and favorable temperatures.
Typical Nest Development Timeline
The development of a bald-faced hornet nest follows a distinct timeline throughout the warmer months. In the initial phase during spring, the queen works alone for several weeks, building the starter nest and raising the first brood. This early nest is small, often only a few inches long.
The rapid growth phase begins in early to mid-summer when the first generation of workers matures and takes over construction. During this period, the nest expands most quickly due to the increasing worker population, which can reach hundreds of individuals. Nests can grow significantly, with daily additions visible and an increase of several inches in diameter per week during peak activity.
By late summer or early fall, the nest reaches its maximum size before the colony declines with colder weather. A mature bald-faced hornet nest can become quite large, often reaching the size of a football or basketball. Typical dimensions can be up to 24 inches long and 18 inches in diameter, with some nests even reaching 3 feet in height. The entire process, from the queen’s initial work in spring to the nest’s peak size, typically spans from April or May through late summer or early fall, with nests being abandoned by winter.