Who would consider ants farmers? Farmer is not a vocation naturally assigned to these tiny insects. The fact is that they herd and care for aphids to keep a much-loved food in constant supply. Aphids and ants on plants are as interdependent as Idli & sambar. I saw this Camponotus Ant on the underside of the Rattlepod (Crotalaria pallida) leaf tending aphids. Here I have used Canon EOS 5DS R coupled with Canon EF 100mm f/2.8L Macro IS USM and 56mm Kenko extension tube It was illuminated with Godox Ving V860c E-TTL Li-ion Camera Flash With modified softbox.
Aphids are soft-bodied insects that use their piercing-sucking mouthparts to feed on plant sap. They usually occur in colonies on the undersides of tender terminal growth. Heavily infested leaves can wilt or turn yellow because of excessive fluid removal. While the plant may look bad, aphid feeding generally will not seriously harm healthy, established trees and shrubs.
A fungus called sooty mould can grow on honeydew deposits that accumulate on leaves and branches, turning them black. The appearance of sooty mould on plants may be the first sign of an aphid infestation.
Aphids feed on the sap of plants and secrete a substance called honeydew. This sticky sugary resin is a favourite food of ants, who actually “milk” the aphids for it by stroking their abdomen. That is why sometimes aphids are called “ant cows”. You can check the first photo where the ant is stroking the aphid to extrude the honeydew. The relationship between aphids and ants is symbiotic in that both receive some benefit from the arrangement. Animals and plants in a mutually symbiotic arrangement with ants are called Myrmecophiles.
The unique relationship between these two organisms provides protection for the aphids and food for the ants. Aphids protect ants from predators, such as lacewings and ladybugs. Ants have also recently been found to safeguard the aphids from a fungal outbreak that causes death, by removing the bodies of the infected aphids. Anytime you see a large number of ants on a tree or plant; it is likely you have a large infestation of aphids. Not all species of ant find this arrangement beneficial, but many of the more common species do indeed farm them.
Chemicals on ants’ feet tranquilise and subdue colonies of aphids, keeping them close-by as a ready source of food. The ants have been known to bite the wings off the aphids to stop them from getting away.
It is a fascinating arrangement where aphids and ants on plants live in close cooperative proximity. Farmed ants supposedly produce larger drops of honeydew and more offspring. The sweet sticky stuff is a favourite food for ants, who also take it back to feed larvae. Plants, where there are aphids farmed by ants, may appear to be overrun by insects.
If you want to control aphid menace, then you can take any one the following strategy. Managing ants are one way of controlling the aphid population. Ant bait stations are efficient because the ants take the bait and bring it back to the main colony. With fewer ants to defend them, aphid numbers will drop. A non-toxic method is to just wrap the plant or tree with sticky tape or netting which catches the ants and prevents them from tending to the aphids. In turn, the aphids get exposed to predators, and their numbers will dwindle. Conversely, you can focus your attention on the aphid population. Without aphids, the ants will be forced to move on for food. Horticultural soap sprays or neem oil work well for aphid control.
Check my earlier two blogs on the same topic – Camponotus Ants Tending Aphids & Camponotus Ant Tending Aphids