Organic matter resulting from the decomposition of plants and/or animals and/or their products.
A mixture of decayed vegetation on the forest floor.
Layer of organic matter resulting from decomposition of organisms and their parts.
The final product of rotting organic matter, whether of plant or animal origin.
In botany, a complex of incomplete decomposed organic materials in the soil.
Decomposed or decomposing organic material in the soil.
The organic content of soil, in nature derived mostly from fallen leaves, twigs, bark, and dead roots. These are broken down by insects and other ground fauna at the same time as they are being decomposed by fungi and bacteria. Earthworms are important in distributing humus throughout the topsoil. The humus content of soil can be enriched with many organic materials, including manure, compost, dead leaves, peat, and composted sawdust or pine bark. Humus returns nutrients to the soil and improves its texture and water retentiveness.