Do Earthworms Eat Vegetable Roots?

Earthworm Diet

• The earthworm (Lumbricus terrestris) depends on the abundance of decaying plant matter and soil for its survival. Its primary diet consists of anything organic, including decomposing plant materials such as leaves, stems and roots. The worms help the process along by breaking the already decayed matter down into even smaller bits, digesting them and redepositing them in the soil. While earthworms consume mainly dead and decaying vegetable plant roots, they do eat live red clover (Trifolium pratense). In addition to dirt, other earthworm delicacies include animal manure and dead animals, as well as the dead leaves of trees such as maple (Acer), birch (Betula) and ash (Fraxinus).

Food Availability

• Earthworm populations are capable of consuming 2 tons of organic refuse per acre in a year. For that to be possible, though, organic materials must be present in sufficient amounts and of a certain quality to sustain them. In soils that contain too much carbon and not enough nitrogen, vegetation takes longer to break down, providing less material for earthworms to process. Adding manure to the soil improves digestibility and makes it more appealing to the worms.

Types of Earthworms

• Earthworms are classified into three major groups: anecic, or subsoil dwellers; epigeic, or topsoil dwellers; and endogeic, or litter dwellers. Among the subsoil dwellers, the nightcrawler is the most common. The large reddish-brown worms grow to 6 inches, eat fresh organic matter near the soil's surface and redeposit their excrement, or castings, in tunnels that sometimes measure 9 feet deep. They constantly reincorporate decomposed litter and minerals into the soil, aerating it and facilitating drainage in the process. Topsoil dwellers, feeding solely on above-ground litter, exist in full view, and their bodies are camouflaged for their own protection. Litter dwellers live exclusively under logs or shallow layers of litter and are a whitish gray color. They process leaves or other organic debris, resulting in beneficial blends of these materials with minerals found in the soil's upper layers.

Benefits

• An earthworm has a mouth but no teeth, and it uses its mouth along with its pharynx, or throat, to grab onto leaves and pull them into its body. The leaves are moistened with saliva, then moved through the esophagus to the crop, where they are stored before being moved to the gizzard. Here they are ground up. The intestines finish the job before redirecting some of the leaves into the worm's bloodstream and the rest out as castings, which fertilize the soil. Earthworm activities stimulate the development of soil microbes that break organic matter down into a size that is readily absorbed by plants. The tunnels that earthworms create make it easier for plant roots to develop, creating pathways for the roots to travel as they elongate.