Killing hornets is much like killing wasps except hornets are less aggressive towards people and eat insects making them beneficial. Wasps begin by eating insects and then change to eating sweet things making contact between them and people more often causing problems. Hornets only eat insects making contact between them and people less frequent. Hornets are also less aggressive and will only attack if they feel their nest is at risk of attack. However wasps will be a pain if you have food that they want. Killing hornets can be done pretty much in the same ways as wasps are killed. Locating their nest should be you first job. Nest are normally built in a hollow tree, wall cavity, chimney, loft space, eaves of a house etc. Products are available that can be sprayed from a distance into the entrance of the nest, killing the hornets. Before killing, protecting your self is very important. Make sure all your skin or as much as possible is covered by some form of clothing. Layers are also a good idea to help prevent a hornets sting reaching your skin. The best time to attack a nest is when the sun has gone down and before it rises again as they will all retreat to the nest then.