Kidnocker: With the monsoon comes ants

Each year during the monsoon we seem to be inundated with ants of various sizes, colors and dispositions. Most are tolerable, but some are a real nuisance especially around the house and garden.

During the summer rainy season certain ants grow wings and form swarms. They fly about looking for the right place to establish a new colony. Ant clouds can be seen around lights at night.

Although sometimes referred to as “white ants”, termites belong to an entirely different order of insects. Termites are light colored, while most common swarming ants are dark. Termite bodies consist of two sections, the head and the body. Ants have three segments: the head, the thorax, and the abdomen separated by an apparent waistline.

Both ants and termites have four wings which are shed soon after swarming. Front and back wings of termites are equal in size and at least as long as the body. The fore wings of ants are long, but do not exceed body length.

There are as many as 20 ant species in Pima County. Much like earthworms in other parts of the country, they are valuable for aerating and turning the soil and helping decompose organic matter. Low on the food chain, ants are important to the diet of birds, lizards, spiders, and many other insects.

It is incredible how fast a troop of ants can devour food spills and dead insects, helping to clean up the environment. They may also be predators, eating live insects, again making them beneficial in the garden.

Harvester ants are among the most common. They form trails, carrying bits of leaves, seeds, pieces of stems, and other plant materials. Primarily seed eaters, these ants work during the daylight hours.

Nests of harvester ants are flat with a noticeable entry in the center. A large area around the nest is cleared of plant material, with empty seed casings stacked nearby. When disturbed, harvesters can cause a painful sting.

Leafcutter, or farmer ants, are among the most frustrating in the garden. They harvest leaves at night, after selecting a favored plant from which to work. The stolen leaves are not eaten by the ants, but are used as a form of fertilizer for their “fungus farm.”

The food source for leafcutter ant colonies is a specialized fungus that is grown in the nest area. They pick a shrub or tree perhaps several hundred feet from the nest and begin their harvest. Worker ants swarm over the plant and cut circular pieces from the leaves. The circles are then dropped to the ground, where the “transportation workers” are waiting to carry the leaf pieces back to the colony.

It is possible for leafcutters to completely strip a shrub or small tree in one night. In the nest the leaf pieces are cut into even smaller pieces and added to their “garden of fungus.”

At The Arid Garden, leafcutters have for several years chosen the same thorny Crucillo tree as their favorite. On summer mornings a bright green trail of leaf parts is evident as it winds its way toward the nest entrance 10 feet away. By the time folks arrive in the garden, there is not a leafcutter in sight, only the remains from a hard night’s work. So far, the older tree has been able to withstand the periodic harvest of its small leaves.

Leafcutter ant colonies produce crater-shaped mounds which surround their entrance. Some nests have been recorded to contain more than 1 million ants and go as deep as 15 feet underground.

Tiny fire ants do not have a defined nest. If accidentally disturbed, they will repeatedly sting, causing an intense long-lasting burning and itching. These natives are different from the tiny “pharaoh” ants that often invade our homes, but neither sting nor bite. Pharaoh ants are searching for sugars and fats that we and our pets consume.

To get rid of ants, there are a number of commercial products available, many containing boric acid and pyrethrum. Consult a local hardware and carefully follow package instructions. Licensed pest control operators can also be consulted.

To do it yourself, cayenne pepper, lemon juice, coffee grounds, citrus oil, tree tea oil or diatomaceous earth may be applied at colony entry points. Contact sprays may also be made from these items, or mint extract, Tabasco sauce, and organic bio-degradable soapy water.

Getting rid of all ants is unlikely, so plan to simply manage the numbers. Many will disappear when the rainy season does, so be patient!

Mary Kidnocker is a Master Gardener who writes frequently about the subject from a local perspective. Her columns are featured each Sunday.