Have you ever stopped to think about how much trash you throw out every year? At several bags a week, it’s no wonder that Americans generate about 210 million tons of trash each year. Sadly, most of that trash (57 percent) is ending up in municipal landfills. About 27 percent is recovered through recycling and composting. Recycling is the reusing of glass, paper products, plastics, or metals. Composting is used to deal with yard waste and organic material. Composting works by breaking down organic material in the presence of oxygen to the point where it can be safely stored, handled, and applied to the environment. The end result of composting produces finished compost, or humus, which can be used as a natural fertilizer for gardening and farming. So whether you’re studying composting for a science project, or you’re seriously considering applying it to your every day life, understanding the biology of composting is the first step.