Garden Ants - Advice for identifying and controlling

What do they look like?

The worker garden ant is a large ant 3-5 mm in length and dark brown to black in colour.  The Queen is about 12mm long and slightly lighter in colour.

How can you spot them?

The black garden ant is the most common and is found in almost all parts of the country. The ant is an active insect and nests outside, in grass, walls and under paving.  It enters buildings in search of food.

How do they affect humans?

Foraging worker ants cause a nuisance as they travel widely in search for food, usually following well-defined trails and clustering around a food source.  Ants may cause considerable nuisance by invading food prepared for human consumption.

The Life Cycle

Ants live for about two months, but in good conditions a nest can last for years.  Flying ants are the reproductive males and females.  These mating ants are winged and have a nuptial swarming flight (which is a nuisance but harmless) which occurs during only a few days in July or August.

After mating the male dies and the female loses her wings and buries herself in the soil over 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 forming the well-seen ant eggs.  The worker ants which emerge from the pupae feed new larvae and the queen.  The entire cycle takes about 2 months to complete and under favourable conditions a nest may persist for several years.

How do you control them?

In many cases where ants are a problem indoors it is because they have either established a nest beneath the foundations or very close to an outside wall and are finding their way into the building.

The nest entrances are identified by small piles of earth pellets or they can be located by watching the ants moving back and forth from nest to food.  Boiling water poured on the nest will control the infestation for a short time.  Follow this by puffing an insecticidal powder product into the hole.  Select a powder product which lists ants on its label.

Other ways to control ants includes applying a contact insecticide, e.g. ant powder, or use a gel placed on, for example, a small piece of glass, which the worker ants feed on and take back to their brood within the nest.  If persistent, the gel may eventually destroy the nest.  If you decide to use a powder it should be applied to cracks and crevices along and under skirting boards where ants are a problem.  A small amount of powder should be applied to the floor and using a small paint brush, dusted into cracks and crevices.

Practical Advice

Read the label of any container or box before using an insecticidal powder or gel.  Do not apply insecticide on the outside walls of properties as the colony may be underneath the foundations.  This could stop the ants foraging in the garden and so compound the problem indoors.

Ensure that sugary foods are kept in sealed containers and all food spillages are cleared up.  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 the necessary precautions when applying the product.

Treatment

North Shropshire District Council does offer a service for the treatment of ants (inside house only).

For people receiving the following benefits:

• Income Support
• Income Based Job Seekers Allowance
• Working Tax Credit
• Benefit
• Council Tax Benefit
• Pension Credit (Guarantee Element)

the charge is £20.00.  If you do not receive any of the above benefits, the charge is £40.00.

Related Documents

The Control of Ants

Cluster Flies leaflet - 2008/09