Department of Defense Calls for Biodegradable, Seed-Planting Ammo

These seed bombs could make Army training easier on the environment

Spent shell casings pile up as a soldier fires his weapon during a U.S. Army weapons qualification. U.S. Army/Sgt. Roman Hale - Flickr

Every year, the U.S. Army uses hundreds of thousands of rounds of bullets for training purposes. That means plenty of metallic waste—refuse that can take centuries to break down. But one day, that training trash could turn into environmental treasure. As PCMag’s Matthew Humphries reports, the Army wants to take that ammo and use it to plant seeds.

The Department of Defense recently made a request for biodegradable, seed-planting training ammunition, reports Humphries. The document lays out a plan to replace the current components used in training rounds with biodegradable materials that contain seeds that “grow environmentally friendly plants that remove soil contaminants." The report also notes, "animals should be able to consume the plants without any ill effects."

If the plan ever comes to fruition, it could help reverse the environmental damage wrought by Army training. The ammunition the Army seeks to replace with the biodegradable bullets include everything from mortars to artillery rounds—materials that, while ranging in size, can cause significant environmental contamination. The Army suggests that potential manufacturers use biodegradable polymers like those found in modern-day compostable plastics for the bullets.

It’s hard to pick up empty shells, especially in the field, and often cases and materials end up buried beneath the ground. There, they leach out chemicals that can contaminate soil and make their way into groundwater. The Army’s concept is to use the ammunition to, in effect, clean itself up thanks to seeds embedded inside the ammo that will eventually sprout when the structure biodegrades.

Wondering how the seeds will last long enough for their packaging to break apart? The Army has an answer for that: newly bioengineered seeds developed by the U.S. Army Corps of Engineers. At its Cold Regions Research and Engineering Laboratory, the Corps has already demonstrated seeds bioengineered not to germinate for several months. By the time they’re ready to grow, they’ll be inside the soil where they belong and presumably ready to sprout.

Despite the Army’s use of so much ammunition, it does have controls and guidelines in place that discourage the waste of training ammo. But even if the Army does eliminate the physical remnants of future training munitions, past training efforts have had an indelible effect on the environment. For decades, the Army has attempted to remediate and restore sites contaminated with hazardous chemicals from training facilities, but its efforts are far from complete. There’s no telling how long it will take to clean up the environmental effects of past training efforts—or whether research will someday yield a bullet that can biodegrade. Maybe, though, the Army of the future will do Earth a favor even as it prepares for war.

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