Silage is a type of preserved forage made from green crops like grass, corn, or sorghum that are cut and stored under anaerobic (oxygen-free) conditions. This process, known as ensiling or fermentation, converts the sugars in the plant into acids (mainly lactic acid), which preserves the forage and retains its nutritional value for livestock feeding. The anaerobic environment is key, as it prevents spoilage by harmful microbes, allowing the silage to be stored for extended periods without significant degradation.