Yellow jackets (genus Vespula) are social wasps known for their distinctive yellow and black markings and aggressive behavior. The answer to whether they nest in the ground is definitively yes; ground-nesting is a common habit for several species, including the Eastern and Western yellow jacket. Yellow jackets utilize existing voids in the landscape to establish their colonies, turning an inconspicuous hole into a bustling, hidden nest. This subterranean activity often leads to accidental and painful encounters for people working in their yards.
The Ground Nesting Habit
Yellow jackets select the ground for its inherent protection and insulation, establishing their colonies in pre-existing cavities rather than digging them from scratch. They commonly repurpose abandoned rodent burrows, such as those made by mice or chipmunks, or natural voids found beneath tree roots, logs, or retaining walls. These locations offer a confined space that helps regulate temperature and humidity, which is beneficial for developing larvae.
The entrance to a ground nest is typically a small, unadorned hole that is easily overlooked in lawns or dense landscaping. The most reliable way to identify a nest is by observing the constant, heavy traffic of workers flying in and out of this single opening. Unlike solitary ground-nesting bees, a yellow jacket colony exhibits a persistent, agitated stream of wasps near the entrance, especially during the warmer parts of the day. This “airport activity” signals the presence of a large, active social colony just below the surface.
Anatomy of a Subterranean Nest
The physical structure of a yellow jacket nest found underground is concealed entirely within the soil cavity. The wasps construct the nest using a paper-like material, known as carton, which is created by mixing chewed wood fibers with their saliva. This pulp is formed into a series of horizontal, multi-tiered combs that house the developing brood.
The subterranean location provides the crucial protection of the surrounding earth, allowing the workers to focus on expanding the internal structure. The nest starts small in the spring but grows rapidly throughout the summer, often reaching the size of a basketball or larger by late summer or early fall. The internal combs are enveloped in multiple layers of the papery carton, which provides insulation and helps maintain a stable microclimate. A mature nest can contain thousands of individual cells and workers, making late-season discoveries hazardous.
Identifying Yellow Jackets vs. Look-Alikes
Correctly identifying a yellow jacket is important because many other ground-nesting insects are frequently mistaken for them. Yellow jackets are characterized by their smooth, shiny bodies, which lack the dense hairiness found on bees. Their body tapers distinctly at the waist and displays a vivid pattern of yellow and black banding. This differentiates them from other wasps, such as the paper wasp, which has a more slender waist and dangles its legs in flight.
Behavior is another identifier, as yellow jackets are known for their aggressive, persistent flight pattern, especially when their nest or a food source is disturbed. Ground-nesting bees, often misidentified as “ground bees,” are solitary and docile, rarely stinging unless directly handled. If a small hole in the ground features a continuous, high-volume flow of agitated, sleek, black and yellow insects, it is highly likely a yellow jacket nest and should be avoided.