Maize leftovers in the US Midwest are vital for making environmentally friendly biofuels. Researchers used a special model to predict how much biofuel we could make and how it affects greenhouse gases. By tweaking farming practices, like using cover crops, we could produce a lot more ethanol while still meeting eco-friendly standards. Right now, we can only make about 5.3 billion liters each year, but with some changes, we could hit 89 billion liters. Adjusting how we manage maize leftovers can boost biofuel production and help the environment at the same time.