Watch Drones Drop Thousands of Moths on Crops

Swarms of sterile moths could be coming to a cotton farm near you

Using Moths To Control Crop Damage

Drones can swarm a military enemy, tour historical sites and even collect whale snot. Now, they are helping out cotton farms in a pilot program that is a new spin on crop dusting. Instead of chemicals, these drones drop hundreds of thousands of irradiated moths, Mary Beth Griggs reports for Popular Science.

Though seemingly bizarre, the USDA has strong motivation for the project: A plague of pink bollworms. Long considered an invasive species, these worms are a cotton field’s worst enemy. They lay eggs on cotton bolls, and their babies eat both cotton seeds and fibers, ruining crops and destroying their long-term viability. Even worse, the pink bollworms are largely resistant to many toxins.

The National Cotton Council estimates that these worms cost about $21.6 million in prevention, control and cotton loss every year—a cost so high, it has sparked a nationwide movement to devise new methods for bollworm elimination. 

So in a creative new effort, the USDA employed a fleet of drones to drop irradiated moths on infested cotton fields, writes Griggs.

But why irradiated moths?

Heidi Ledford explains for Nature: Scientists grow moths from bollworms in a lab and sterilize them with radiation. The moths are then dropped out of planes and mate with bollworm moths on the ground. The hope is that these sterile moths will overwhelm the cotton crop's moth populations, and since sterile moths can’t reproduce, there are no pesky baby bollworms to munch on the cotton.

This "risky approach" was was first tested in 2005 in Arizona, reports Ledford, by throwing the moths out of canvassing planes by hand. The program was a smashing success. After four years of moth drops, the irradiated bugs wiped out Arizona's infestation by 99.9 percent.

The USDA's Animal and Plant Health Inspection Service is now hoping to streamline the process, using drones to do the dirty work. Drones are more nimble and less expensive, quarantine deputy administrator Osama El-Lissy explains in the video.

If the pilot program goes well, the USDA hopes to implement the project on a wider scale, and everyone will need to pay a little more attention to the skies to stay out of the draft of these moth-dropping machines. 

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