There are, of course, some technical hurdles to overcome. The right kind of biodegradable composite would have to be tough enough to handle cycling through a firearm and the high temperatures it would be exposed to when fired, not to mention all the other forces exerted upon it on the way down the barrel and to the target. It would also have to be ballistically similar, if not identical, to the actual ammo individuals would be training to use. Plus they have to hold seeds, and protect those seeds from aforementioned high temperatures. That’s a pretty tall order.