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Ants

Description

There are two species of ant commonly encountered in the UK:

• The Garden ant
• The Pharaoh’s ant

The Garden Ant has a black segmented body, the workers are 5mm in length and the queen is 15mm long and brown in colour.  Their nests are found in soil, lawns and close to buildings.

The Pharaoh’s Ant, which is of tropical origin, is a smaller species; the workers are only 2mm long, the queen 5mm long and both are yellow brown in colour, sometimes with a darker abdomen.

Distribution

The Garden Ant is found throughout Britain and will nest in gardens and around buildings often entering premises in search of food.  The Pharaoh’s Ant by contrast requires a very warm environment and has adapted itself to life in large heated buildings such as hospitals, hotels and flats.

Significance

The Garden Ant is a nuisance because of its foraging habit but it does not carry germs or spread disease.  Garden ants are attracted to sugary food; the presence of ants in food although unpleasant, does not in itself constitute a health risk.

Pharaoh’s ants are of greater significance as they carry harmful germs which they pick up when feeding on decomposing food, faecal matter and when coming into contact with drains and hospital dressings.  They are a particular problem in hospitals and are difficult to eradicate.

Life cycle

Garden ants mate in flight when winged males and females swarm between mid-July and mid-September.

After mating the male dies and the female loses her wings and buries herself in the soil over the winter.  In late spring the female lays eggs which hatch into white larvae in 3-4 weeks.  The larvae are fed by the queen and when fully grown pupate.  The worker ants which emerge from the pupae feed new larvae and the queen.

The life cycle is complete in two months and, in favourable conditions, the nest may persist for several years.  In contrast, the Pharaoh’s ant develops several colonies within each nest with many queens.  As the old nest becomes overcrowded, new colonies are formed by eggs and larvae carried by adults and workers.  The life cycle is the same as that of the Garden ant but the Pharaoh’s ant, which favours heated buildings, is not affected by seasonal changes.  The ants’ ability to form many colonies make them difficult to control.

Control

There are several measures that you can take to control Garden ants:

• Boiling water poured on the nest will control the infestation for a short time at least.
• Followed by puffing a residual insecticidal powder product into the hole. Select a powder product which lists ants on its label.
• Ensure that sugary foods are kept in sealed containers and all food spillages are cleared up.
• Flying ants should be controlled by using an appropriate insecticidal aerosol for flying insects.
• A residual insecticidal laquer can be applied around door thresholds, wall/floor junctions, windows, ventilators, ducts and drains, in fact anywhere you can see ants run. Attention should be given to small cracks.
• Some products cause the workers to destroy their own nests, for example sugar based liquid bait containing borax. The workers are attracted to the bait and carry the insecticide back to the nest.

Some products on the market are harmful to pets, others are not.  It is important that you read the label and follow the instructions taking all necessary precautions when applying the product.

An infestation of Pharaoh’s ants must be professionally treated.