A research study involving harvester ants was recently conducted in Spain. The results were highlighted by Penn State with full results of the study published in the January 2019 issue of Biological Control. If the known facts are any indication, organic farmers may have additional practices to establish for a more sustainable operation.
The study was designed to determine what differences were occurring in harvester ant populations between tilled and no-tilled fields. Although the findings are not necessarily new concepts, they are confirmation of what most environmental scientists and farmers have already suspected.
In the no-tilled fields, the ant nests were more evenly distributed and larger in size. This combination has allowed the harvester ants to feed their colonies while greatly reducing weed pressure. Every time a field is tilled, weed seeds get pushed deeper into the soil making it harder for ants to retrieve them. Tilling also reshapes or destroys colonies, leaving smaller population numbers in concentrated areas. With fewer ants to remove the weed seeds, there will be more green weeds to remove from a given field.
While it’s ideal to adopt a complete no-till method to farming, it’s sometimes unavoidable. With that in mind, this study suggested tilling one time a year; in the fall. This time period allows the ants to harvest weed seeds and establish generously sized colonies.
Although flying insects help to achieve plant pollination, they shouldn’t be of exclusive focus. The insects in and on the ground also play an important role in the health of our food and ecosystems.