Wasps will usually nest in the ground, but will nest also in wall voids, railroad ties, and other above ground locations. Many homeowners see, "bees", flying around their hedges. These "bees", are usually Yellow Jackets, a type of wasp. In the Spring, most Yellow Jackets will feed on insects in and around the foliage. In the Fall, Wasp colonies have become the largest size, and foraging workers may be a serious nuisance as they search for food people eat or discarded food. If a colony is disturbed, they can become very aggressive and sting. For most a sting is temporary, put painful. For allergic individuals a single sting may result in a serious reaction, requiring medical attention.