While shadowing a 5th grade field trip, a student asked me “Why does everyone look down at the ground when they hike?” I suggested perhaps it was due to the rough trails, maybe taking care to not step on small wildlife, or wanting to keep an eye out for animal tracks and other hard-to-spot features.
However, some features don’t require a sharp eye or focus and attention to detail to be spotted. Consider the mounds built by Allegheny mound ants: approximately 36 inches in diameter and about one foot high, these mounds are hard to miss. The large, bare piles of dirt, housing around 6,000 ants, can tell us a lot about the landscape.
The dirt is bare for an important reason. The sun’s warmth is necessary for Allegheny mound ants and their eggs to thrive, so ants clear away any plants encroaching on their space. Just like us, ants manage their lawns, removing surrounding vegetation by injecting the stems with formic acid; we use lawn mowers and weed killer to manage our green spaces.
We humans clear and change the land on a variety of scales, from basic lawn care to industrial agriculture. Farmers remove vegetation from an area to use the land for growing crops or grazing livestock. When the field is no longer in use, or gets abandoned, Allegheny mound ants take advantage of the sunny location and move in. The Parklands provides great habitats for the ants, such as mown trail shoulders and open, sunny fields. Eventually, cedar trees will outpace the ants’ landscaping efforts, blocking the sunlight and causing the ants to leave their sprawling underground galleries and mound in search of sunnier pastures.
But the life of the ant mound is not over so soon. The bare dirt slowly takes on a hint of green as moss creeps its way over the surface. The abandoned ant hill will remain intact for many decades, a mossy mound on a shaded forest floor.