Animal waste, otherwise known as manure, is a valuable source of crop nutrients that can improve physical and biological properties of soil. Manure contains primary macronutrients—namely nitrogen, phosphorus, and potassium—meaning it can substitute for or complement commercial fertilizers. Manure also supplies secondary macronutrients such as calcium, magnesium, and sulfur, as well as micronutrients. In addition, manure provides organic matter and carbon, which makes it useful for improving soil health.