Hornets, belonging to the Vespidae family, are large social wasps known for their defensive nature, especially when their nest is threatened. Species like the Bald-faced or European hornet often build colonies near human activity, prompting the need for control. Since chemical pesticides pose risks to the environment and beneficial insects, many seek effective, non-chemical alternatives. These methods focus on natural techniques to prevent, incapacitate, and safely remove hornets.
Safe Identification and Prevention
Accurate identification is the first step, as hornets are often confused with less aggressive bees or other wasps like yellowjackets. Hornets are generally larger and have smoother, less hairy bodies compared to fuzzy bees. The Bald-faced hornet, which is actually a type of yellowjacket, has black and white markings, while the European hornet has a reddish-brown and yellow pattern. Understanding the species helps determine the appropriate control strategy.
Preventative measures focus on making the surrounding area less appealing to discourage new nests. Hornets are attracted to food sources, so securing outdoor garbage cans with tight-fitting lids removes a significant draw. Promptly collecting fallen fruit from trees eliminates a sugary food source that sustains foraging individuals.
Exclusionary tactics can deter them from nesting in or on structures. Sealing cracks, crevices, and unsealed entry points to attics, sheds, or wall voids prevents them from establishing a sheltered colony. Hanging a decoy nest, such as a simple paper bag, may also discourage hornets from building nearby, as they are territorial and avoid nesting close to an existing colony.
Direct Contact Killers
A highly effective non-chemical method for instantly incapacitating hornets involves a simple solution of liquid dish soap and water. This mixture works by physical means, making it safe to use around gardens and food sources. The soap acts as a surfactant, breaking the water’s surface tension, allowing the solution to penetrate the insect’s protective waxy exoskeleton.
Once the soap solution coats the hornet, it clogs the spiracles, the small external openings used for breathing. This physical obstruction prevents the insect from taking in air, leading to rapid suffocation and death. A common ratio involves mixing about two tablespoons of dish soap for every two cups of water, applied with a spray bottle or pump sprayer for distance. Apply this substance at dusk or dawn when the insects are less active and most are inside the nest.
For nests located in the ground or concealed in wall voids, food-grade diatomaceous earth (DE) can be used as a contact killer. This fine white powder is composed of the fossilized remains of diatoms, which are microscopic, sharp-edged particles. When a hornet crawls through the dust, the sharp particles lacerate its waxy outer layer, causing abrasion. The powder simultaneously absorbs the oils and fats from the exoskeleton, leading to fatal dehydration.
Passive Lures and Traps
Passive traps are useful for managing the foraging population and are effective for capturing individual worker hornets away from the main nest. A common approach involves creating a DIY trap from a two-liter plastic bottle by cutting off the top section and inverting it into the base to form a funnel. The hornet enters through the funnel, but the design makes it difficult for the insect to find its way back out.
The bait used in these traps should be adjusted according to the season, reflecting the hornets’ dietary needs. In the spring and early summer, hornets primarily seek protein to feed their developing larvae, making baits like meat scraps or tuna effective lures. As the season progresses into late summer and fall, the adults switch their preference to high-energy sugar sources. Sweet liquids serve as better attractants for worker hornets during this time. Adding a drop of dish soap to the liquid bait ensures that any hornets entering the trap quickly drown, as the soap reduces the water’s surface tension.
Non-Chemical Colony Eradication
Eliminating an entire hornet colony requires the safe removal of the nest structure itself, not just killing individual insects. The safest time for this action is at night, as hornets are cold-blooded and become sluggish in cooler temperatures, reducing their activity and aggression. Using a flashlight covered with a red filter is recommended, as hornets are less sensitive to red light and are less likely to be disturbed.
For aerial nests that are accessible and not excessively large, a physical removal technique can be employed. This involves placing a heavy-duty cloth or plastic bag over the entire nest, quickly tying it off at the top, and severing the attachment point from the structure. The sealed bag containing the nest can then be submerged in water to ensure any survivors are drowned, a clean and chemical-free method.
Ground nests, often the work of yellowjackets, can be eradicated by flooding the entrance. This involves pouring a large volume of soapy water directly into the entrance hole to quickly drown the inhabitants and saturate the nest material. After the hornets are confirmed inactive, the entrance can be permanently sealed with dirt or cement. If the nest is large, difficult to reach, or involves a highly aggressive species, calling a professional pest control service is the safest course of action.