Pests and diseases: Garden ants

Plants affected

• Garden ants rarely cause damage to plants. However, they feed on sugary foods, oily seeds, honeydew from aphid-infected plants, and other small insects. Heaps of earth around the nest entrance can be a nuisance in the lawn where they interfere with mowing, and they can also partly bury low-growing plants.

About Garden ants

• There are two main species of garden ants, the red ant Myrmica rubra and the black ant, Lasius niger.
• Queen ants fly in from neighbouring gardens all the time but are killed by ants from existing nests. Killing a queen and her nest simply makes space for another. For this reason it is best to focus on controlling only those nests that are causing real problems.
• Adult worker ants are all female, wingless, and around 5mm in length.
• Queens are significantly longer and fatter.
• Larvae are white legless grubs roughly 5mm long.
• Each colony can vary in size from as small as 500 individuals to many thousands.
• After over-wintering, females emerge in spring and lay eggs.
• The first brood will be fed by the queen for three to four weeks before pupating in the soil.
• Adult workers emerge after two weeks to maintain the nest and feed the queen and subsequent larvae.
• When adults find a food source they leave a trail of chemicals known as pheromones back to the nest for others to follow.
• Towards the end of summer winged males and females are produced.
• Between August and September mating takes place during flight.
• After mating, male adults die and females shed their wings and return to the soil to overwinter.

Treatment

Chemical

Products containing the following chemical ingredients are all effective on Garden ants

• Pyrethrins
• Pyrethroids
• There are a large number of pesticides available for ant control although these are mainly for indoor use.

Note: It is important to read manufacturer’s instructions for use and the associated safety data information before applying chemical treatments.

Organic

• Observe foraging ants and follow them back to the nest.
• Dig up nests where possible making sure to remove the queen.
• Encourage insectivorous birds by hanging bird boxes and feeders.
• Place tin cans over the ant hill in the morning. As it heats up, the ants take their eggs up into the can. In the afternoon slide a piece of cardboard under each can, and remove and dispose of the eggs. They make a tasty treat for birds, especially chickens.

Prevention

• Clean previously infested surfaces to remove pheromone trails.
• Use natural predators and parasites to control aphid populations.
• Dig up soil in the winter months to disturb overwintering females.
• Maintain pest-free plants.
• Clean honeydew from any infested plants with water.

Original Article Here