What Are the Fungi That Breakdown Organic Matter Called?

Lack of a General Term

• Fungi that derive all their nutrients from the breakdown of dead organic matter are usually known as saprophytes or saprophytic. Saprophyte is a general term for any plant that breaks down dead organic matter, not only fungi. However, the term is sometimes used incorrectly to describe animals, such as earthworms, that breakdown organic matter. Another type of fungi, known as mycorrhizal fungi, will also breakdown organic matter, but in addition they live in a symbiotic relationship with the roots of trees. Finally, many parasitic fungi will breakdown organic matter but may also extract nutrients from living organisms upon which they are parasitic.

Saprophyte or Decomposer

• The term saprophyte is often used interchangeably with that of decomposer. However, this is a mistake. Decomposer refers to the work that an organism must do -- the breakdown of matter. Saprophyte refers to the "wages" of this work, the absorption of nutrients from dead matter. All saprophytic fungi are decomposers, they absorb the nutrients from the things they breakdown. However, some decomposers may not be saprophytes. For example, some fungi, particularly those living in symbiotic relationships, like lichen, breakdown rock but do not receive nutrition directly from this process.

Saprophyte as an Outdated Term

• Saprophyte is the term that is generally used to describe organisms outside of the animal kingdom that breakdown dead organic matter. This refers almost exclusively to fungi and certain plants, principally orchids. However, researcher J.R. Leake argues in a 2005 paper "Plants Parasitic on Fungi" that the term "saprophyte" should be considered obsolete. It is a term associated with plants that feed on dead matter and as fungi are no longer considered part of the plant kingdom, the label does not apply to them. Furthermore, plants once thought to be saprophytes are now known to live off nutrients extracted by symbiotic fungi, hence there are no examples of saprophytes as the term was originally distinguished. Because fungi do not belong to the plant kingdom, Leaky argues that they should be described as "detritivores," or consumers of dead matter, rather than as saprophytes. However, the word is still commonly used.

Lignicolous Fungi

• Lignicolous fungi are those fungi that are capable of breaking down lignin and cellulose, which are the main components of wood. Taxonomically speaking, this is quite a disparate group, containing members of various distantly related classes and orders of fungi. However, they are grouped into this category for largely practical reasons: because of the threat they pose to woodland and wood products. Non-lignicolous fungi are refereed to, in this instance at least, as terrestrial.