A shortage of cotton and corn? Not quite. But Reebok’s NPC U.K. Cotton + Corn sneaker, which debuted in August, more than a year after the concept was first announced, quickly sold out. At $95, it is the first shoe certified by the U.S. Department of Agriculture as “biobased” and has a 100 percent cotton upper and corn-based rubber substitute sole, in addition to 100 percent recycled packaging. Reebok says the goal is to create shoes that can decompose in six months, rather than end up in landfills. So yes, they can be added to compost or buried for disposal.