Wasps who build nests in the ground can be a particular nuisance, as it's easy to accidentally trample their nests during everyday outdoor activities such as mowing the lawn or gardening. While wasps can be environmentally beneficial, wasp nests in frequently used public areas pose a safety hazard and should be destroyed. Professional exterminators can be hired, though if you want to control wasps in a ground nest on your own, wait for cool weather and proceed with great care.
Observe the nest from a safe distance during the day. Be sure to note all the visible entrances. Mark the location of the nest with an object you'll be able to see easily in the dark, such as a bucket.
Purchase an insecticide suitable for use on lawns and gardens, dictated both by what varieties are permitted for use in your state and by personal preference. Powdered insecticides might be the most effective, as the particles can settle into wasp nests more extensively than liquids, but liquid aerosol formulas may be applied to the nest at a distance of up to 20 feet away. For anyone especially wary of being stung by wasps, this is a distinct advantage.
Venture out to the nest a couple of hours after sunset, as wasps are inactive at night. Approach quietly, make sure there are no bright lights around, and turn off your flashlight, as wasps will be drawn to it. Either sprinkle a powdered insecticide over the entrance to the nest, or stand back and spray an aerosol insecticide directly into the entrance.
Leave the area immediately. Don't stick around to see how the wasps react to the insecticide. Wasps are territorial and aggressive by nature; if they see you, they'll attack.
Scrutinize the nest for activity the next day. If any wasps remain around the entrance to the nest, repeat the process once more after nightfall.