When we talk about locust swarms, we envision biblical plagues and famines in ancient societies. But locusts continue to be a serious problem around the world. Huge swarms of the insects can destroy crops across entire regions and cause massive economic losses.
Arizona State University is the site of a Global Locust Initiative that seeks to reduce the impact of the insects. Locusts are actually the Mr. Hyde version of the Dr. Jekyll form of certain grasshoppers. A small fraction of the world’s grasshoppers undergo a transformation under certain conditions that turns the green, ground-based, mostly solitary insects into massive swarms of winged locusts that travel long distances wreaking havoc wherever they go.
After 18 years of studies, the ASU researchers found that plants growing in nutrient-poor soil promote locust outbreaks. These are plants high in carbohydrates and low in protein. High protein plants are bad for locusts to eat; their bodies cannot handle the extra protein and they don’t get enough energy for their lengthy flights.
The researchers partnered with 100 farmers in Senegal where outbreaks of grasshoppers occur. By treating certain millet fields with nitrogen fertilizer to stimulate higher protein plants, they found three differences from untreated fields. There were fewer locusts, less crop damage, and doubled crop yields.
The farmers were funded by USAID, the program that was cancelled in early 2025 by the Trump administration. Going forward, these farmers cannot afford to obtain the nitrogen-rich fertilizer, but are doing composting to enrich their soil and reduce the severity of locust attacks.
