“Why should I compost?”

“What’s the issue with throwing food in the trash,” you may be wondering,“doesn’t it decompose anyways?”

Unfortunately no, not really. Landfills are designed to store waste, not break it down. To create a landfill, a huge hole is dug, and the ground at the bottom is lined with clay and a flexible plastic. Once full, the landfill is covered with more clay, another plastic sheet, and several feet of dirt, soil, and plants. This creates a very dark, oxygen-free environment, which slows or completely prevents decomposition. It’s possible to find food at the bottom of landfills from decades ago that is still perfectly intact.

Food is organic matter, which means it requires bacteria, fungi, water, and oxygen to decompose. Most garbage arrives to landfills in plastic bags. Inside those bags, covered by many other plastic bags, most decomposers don’t receive enough oxygen to break down the food waste. Since the environment is oxygen free, the bacteria capable of breaking down the food waste must be able to function without oxygen.

This bacteria, the kind capable of functioning in oxygen-free environments, uses a process called anaerobic decomposition to get the job done, which usually results in methane gas production. Methane is a greenhouse gas that contributes enormously to global warming, and its effect on the atmosphere is 20–26 times greater than carbon dioxide. It is also highly flammable, and becomes dangerous when trapped underground. To combat this build up, some landfills release the gas into the air, or collect it to sell or burn for energy, none of which are good environmentally speaking.

Unlike decomposition in a landfill, composting is a aerobic process, meaning it involves the oxygen. This process does not produce methane gas because the microbes that release methane are not active. As the organic waste breaks down, it releases heat that kills any pathogens that may be present, and creates an end product which can be super useful for flower gardening, landscaping, or growing food. When you throw food into the trash, you get nothing in return.

While we should certainly be focusing on reducing our food waste in the first place, composting offers a great alternative to landfills when it comes to disposing of uneaten food and the removal of yard waste. Maybe someday there will be an even better option, but in the meantime, we should all be composting.