Around the world, humans have had significant impacts on our landscapes …clearing vast areas for agriculture, extracting natural resources, and building cities, houses, roads, and much more.
However, we’re not the only species that purposefully alters its surroundings to meet our needs.
In the rain forests of South America, clearings called “Devil’s Gardens” can be found that contain only one to three species of trees. Other examples from around the world can be found where in order to thrive, a plant is able to make it’s surroundings unsuitable for other species of plants to grow; essentially weeding out any competition.
However, in our case of the Devil’s Gardens, a study co-authored by Deborah Gordon at Stanford University determined that there was another, six-legged force behind these mysterious forest openings.
Lemon Ants prefer to build their homes in the stems of the tree species that survive in Devil’s Gardens. As it turns out, this is not a coincidence. In the eyes of a Lemon Ant, other trees not suitable for housing their kin just get in the way and take up valuable real estate.
To make their surroundings more suitable for the continued existence and growth of their colony, it’s the Lemon Ants that rub out any rival vegetation.
To accomplish their role as plant exterminator, worker Lemon Ants will inject the leaves of any undesired shrubbery with formic acid. Within 24 hours the injected plants begin to die. While many ant species carry formic acid as a defense, Lemon Ants are the only known insect to use formic acid as an herbicide.
Researchers estimate that the largest Devil’s Garden observed, was over 1,300 square meters in size and is around 800 years old.