Earthworm

A common name referering to a segmented worm, Phylum Annelida?, class Oligochaeta?, order Opisthopora?. There are over 2,200 species known worldwide, existing everywhere but artic and arid climates. They range in size from two centimeters (about one inch) to over three meters (eleven feet). A common type of earthworm is brownish red, with one thick band of flesh, total length a few centimeters.

Earthworms live by burrowing underground in soil? containing organic materials, which they help to decompose. The worm eats soil as it burrows. The soil is ground up, digested, and the waste deposited behind the worm. This process aerates and mixes the soil, and is often considered greatly helpful by gardeners and farmers. Because a high level of organic matter is associated with soil fertility, an abundance of earthworms is a happy sight for a gardener.

Earthworms are hermaphrodite?s, but cross-fertilize, and lay cocoons giving birth to small but otherwise adult earthworms.

Various species of earthworms are used in vermiculture?, the practice of feeding organic waste to earthworms to decompose (digest) it, a form of composting by the use of worms.

One often sees earthworms come to the surface in large numbers after a rainstorm. They are not leaving the ground to escape drowning as the popular misconception holds, for earthworms do not drown easily. They come to the surface to mate.

External References

http://www.sarep.ucdavis.edu/worms/

http://www.encyclopedia.com/articles/03910.html