The U.S. Army is investigating ways to build biodegradable bullets that will sprout into plants.
In mid-January 2017, numerous news outlets reported on a Department of Defense solicitation for research proposals for the development of “biodegradable training ammunition loaded with specialized seeds to grow environmentally beneficial plants that eliminate ammunition debris and contaminants”. The grant was announced through the DoD’s Small Business Innovation Research (SBIR) program and posted publicly on 30 November 2016.
This grant stems from legislation requiring federal agencies to reserve a fraction of their research funding for small businesses, as described on the program’s website:
The Small Business Innovation Research (SBIR) program is a United States Government program, coordinated by the Small Business Administration, and currently authorized through September 30, 2017, in which all federal agencies with extramural research budgets in excess of $100 million have a percentage reserved for contracts or grants to small businesses.
In the solicitation for the proposal, the DoD states that the requirements apply only to training rounds and not ammunition used in actual combat. They argue that the frequent use of training rounds been an environmental problem for the Army:
Some of these rounds might have the potential corrode and pollute the soil and nearby water. The solution sought by this topic is naturally occurring biodegradable material to replace the current training round materials, eliminating environmental hazards.
This SBIR effort will make use of seeds to grow environmentally friendly plants that remove soil contaminants and consume the biodegradable components developed under this project. Animals should be able to consume the plants without any ill effects.
Though the DoD has not stated specifics, there are a number of methods by which plants can remove toxins from the ground (a collection of processes known as phytoremediation). The DoD solicitation closes on 8 February 2017.