In the fall, yellow jacket and hornet colonies can become quite large in size. If a nest is disturbed, they can become very aggressive and sting.
To control these stinging critters you will need to do several things. First, locate the nest. A yellow jacket nest resembles an airport. The bees take off and land in an almost straight up flight. You can see them zooming in and out as you stand from a distance. Hornet nests will be located in a tree or shrub. Their gray paper nest resembles a football or basketball in size in the summer months. The entrance hole is near the bottom of the structure. Yellow jackets may have several ground entry holes in the area - make sure you find them all. Any treatments should be done at night, because the insects are less active when it gets cooler. Your chances of being stung are greatly reduced with a nighttime assault. Wear protective clothing and try not to use any lights.
Treat the nest with an aerosol wasp and hornet spray that says it sprays up to 20 feet. Most of these products contain a pyrethrum that forms a gas that will fill the cavity, killing the yellow jackets or hornets. Check the nest the following day to see if the yellow jackets or hornets are indeed dead. You can tell this by a lack of activity around the entrance holes. It may be necessary to repeat treatment.
Pouring gasoline on a nest is NOT the way to control yellow jackets. Gasoline will sterilize the soil, get into groundwater, and evaporate into the air we breathe. Gasoline is a mixture of materials, some of which are known carcinogens. When gasoline gets on you it is readily absorbed through the skin, which can also cause a chemically burn. Gasoline has become a popular cure for yellow jackets, with some people pour gasoline into a yellow jacket nest and then light it. One gallon of gasoline has the explosive force equal to 83 sticks of dynamite, which is not good for our environment or our health. Please never attempt to control yellow jackets with gasoline!