Wasps get very bad press, but are a great asset in the garden as they feed on many of the bugs that damage our plants. They become a problem when they build their nests inside the house. Nests are usually found at a height, in the attic, under the eaves or in a hole or vent. They usually come indoors around September when there are fewer flowering plants available to feed on.

They don't carry diseases but they can be aggressive and sting people. They normally only sting as a defence when they feel threatened, and unlike bees, each wasp can sting several times.

Wasps have a painful sting, to which some individuals are more susceptible than others. Generally there is some pain and a small swelling. There are a small number of people who are allergic to bee and wasp stings; on rare occasions a sting can cause anaphylactic shock. A sting on the throat or mouth can be dangerous if the swelling blocks airways. On such occasions please seek immediate medical advice.

Wasps construct nests of a paper-like material, which is a mixture of finely chewed wood fragments and salivary secretions of the wasps. Nest can often be found in the eves of a building or the branches of a dense bush. After hibernating over winter, the fertilized queen wasp, starts her nest building in spring, and lays between 10 and 20 eggs.

Once through the larval stage, the new worker bees that emerge, continue to enlarge the nest and feed the new larvae. Workers prefer to feed on high-energy materials such as flower nectar and fruit. The size of the nest keeps increasing through the summer, as more wasps are added to the colony. Nests reach their peak size in September and can often contain up to 4 thousand individuals.

HOW TO TACKLE WASPS

Important! Wasps or bees should not be tackled without professional help or without a sound knowledge of the risks. Don't try to move a wasp's nest unless you have expert assistance - this is a time to call in the professionals.

Locate the nest by examining all protected areas in the vicinity of wasp activity. Simply removing the nest will not resolve the problem, because surviving wasps will reconstruct a new one. The best strategy is to treat the nest at night when all the workers and queen are present. Spraying into the nests should always be done in late evening or at night.

They are far less aggressive and are all at home. This tactic maximizes the effect of the pesticide application by killing most if not all of the wasps. If treatment is made at night, avoid shining a light directly on the nest or use a red filter on the flashlight. Complete the job by removing the nest, particularly if it is inside an attic, wall void, etc. This service prevents secondary infestations by dermestids or other pests.

It is essential that the paper envelope of the nest not be broken open during treatment or the irritated wasps will scatter in all directions, causing even greater problems. Wasps can be eliminated during the daytime provided you do not stand directly below the nest during treatment. Most wasp sprays cause insects to drop instantly when contacted by the insecticide. Standing directly below a nest increases one's risk of being stung.

SOME USEFUL TIPS

Do not try to pinch a wasp sting out with a tweezers. The sting should be scraped out with your fingernail or a credit card, and the area washed with soap and water.

Hairspray will immobilize bees and wasps; it stiffens their wings. That makes them easier to swat, but does not mean that you can throw caution to the wind when handling them in this condition. They are still quite capable of giving you a nasty sting. Wear gloves and be careful when disposing of these pests.

If you have fruit trees in your garden, consider removing them or regularly removing fruits that have fallen and begun to rot on the ground.

If you are stung in the mouth you should see a doctor immediately as the sting can cause swelling and result breathing problems.