PROBLEMS

Wasps can be regarded as generally useful insects, helping to control other pests and cleaning up dead insect carcasses. They can even act as pollinators, but in general they are regarded as nuisance pests and a threat to health. Many people have a genuine phobia against them, in some cases, with good reason.

Wasp stings may be unpleasant to most of us, but to some they can prove fatal. The ability of these social insects to inflict multiple stings means that for certain individuals, they can kill. Insects are no respecters of rank, the first recorded instance of a fatal wasp sting was the death of King Menes of Egypt in about 3000 BC.

CONTROL

Despite a high mortality rate, the need to control wasps is more and more obvious, especially as the number of infestations appears to be increasing. Requests for control come from two sectors, domestic and commercial and of course, the most pressing time is in the summer months when nests are at their largest. Historically, there have been nine principal ways to apply this control:

• Killing overwintering queens
• Nest destruction
• Insecticidal baiting
• Trapping
• Electric fly killers
• Contact insecticides
• Preventative measures
• Biological control
• Integrated wasp control

The surest way to treat wasps is by destroying the nest. Finding the nest can be a problem in itself although the client may well know its location. If not, a food source can be left as bait for foraging wasps who can then be followed back to the nests, if the nest is close to the food source.

TREATMENT

Ideally, nests should be treated early or late in the day when wasp activity is at a minimum and the nest is likely to contain a high population of workers. The application of an insecticidal dust in and around the entrance of the nest with a dust applicator is effective treatment and returning workers will carry dust further into the nest. They are convenient, ready-to-use insecticides that are white and odourless, ideal for use where people work and live or where food is stored or processed.