In biology, detritus or is dead particulate organic material, as distinguished from dissolved organic material. Detritus typically includes the bodies or fragments of bodies of dead organisms, and fecal material. Detritus typically hosts communities of microorganisms that colonize and decompose it. In terrestrial ecosystems it is present as leaf litter and other organic matter that is intermixed with soil, which is denominated "soil organic matter". The detritus of aquatic ecosystems is organic substances that is suspended in the water and accumulates in depositions on the floor of the body of water; when this floor is a seabed, such a deposition is denominated "marine snow".
Horse feces and straw are forms of detritus, and are used as manure.
Sequoiadendron giganteum (giant sequoia) cones and foliage, sugar pine and white fir foliage, and other plant litter constitute the duff layer that covers the ground of Mariposa Grove in Yosemite National Park, United States.
Feces are the solid or semi-solid remains of food that was not digested in the small intestine, and has been broken down by bacteria in the large intestine. Feces contain a relatively small amount of metabolic waste products such as bacterially altered bilirubin, and dead epithelial cells from the lining of the gut.
A pet waste station in Tucker, Georgia, US
Cyclosia papilionaris consuming bird droppings
Horse feces
Sign ordering owners to clean up after pets, Houston, Texas, 2011