Ants are a sign of another issue

If you have those annoying little brown Argentine ants tracking up and down on your citrus trees it is usually a sign of another issue, the ants are just the messengers.

The very invasive little Argentine ant is an extraordinary survivor and a great deal maker.

Forming symbiotic relationships with other insects, ants will transport an insect from one plant to another for the return payment of collecting up the “honeydew” secreted by the insect. This is particularly evident in the relationship between ants and scale.

Scale can be very damaging to citrus trees if left unchecked, and it relies on ants to move it about.

The honeydew secreted by scale can also attract black sooty mould – These black dusty markings are another tell-tale sign that you have the insect, scale.

When you look closely at your tree, you’ll notice tiny spots or little round lumps, these are the scale insects, they can be black or brown or white. Usually, they gather in clusters and can be found on leaf, stem and on the fruit.

A simple and safe remedy is to spray with a pest oil, or a white oil, available in garden centres and departments. Follow the recommended amounts per litre and cover the tree thoroughly as directed. Importantly you must perform the at least three times at 10-day intervals to make sure that you’ve knocked off each cycle of the scale.

Older scale insects may remain on the tree even when they are dead, they’ll be dry and lifeless and cause no harm.

Tepid soapy water (use a pure soap) thrown over the tree, every so often will remove any black sooty mould and dead scale. The ants will have no reason to be travelling the citrus tree highway with their scaly companions gone, they’ll move on also.

If you have citrus in pots and ants are in the potting mix this is a sign that the pot is too dry. Ants will only nest in dry pockets, so please make sure you thoroughly water your pots.