Soils that are depleted or heavily leached are often acidic. Soils can also become acidic from the high use of chemical fertilizers. Acidic soil inhibits the bacteria that help organic matter to decompose. Acidic soil makes some nutrients less available to crops. A good soil has a lot of organic matter. Organic matter includes all living and dead material from plants and animals. The dead material that has been broken down into tiny particles of less than 2 millimetres is called the “particulate organic matter. Soils with many of these particles become soft, rich in nutrients, and can hold more water.