Why are worms important?

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Worms live in the soil, where it is dark and moist. Worms are photophobic, meaning they do not like the light. They will always stay inside the soil unless it is rainy, when the environment is wet and relatively dark. This is why you sometimes see worms on the sidewalk after a rain!

There are over 9,000 different species of earthworms! About 187 of those species have been identified in the United States.

Worms will eat a wide variety of organic materials such as paper, manure, fruit and vegetable waste, grains, coffee grounds, and ground yard wastes. 

A worm has a very basic anatomy (or body parts) with a simple digestive system. They have a brain, but no eyes! Check out this diagram to see the basic anatomy of a worm.

Worms have a head end and a tail end. In earthworms, if they are split in half at the clitellum (middle), only the tail end will regenerate, and the head end will not. In some cases, though, the tail end will generate another tail end by mistake, and the worm will not survive. A worm must have a head end and a tail end to survive!

The vast majority of worm species are actually parasitic worms, not earthworms. Parasitic worms infect people and animals in a harmful way. Parasitic worms definitely cannot be used for composting. In addition, not every earthworm is good for composting! More than 9,000 species of earthworms have been identified, but only seven species are suitable for vermicomposting. Only one is typically used in North America: Eisenia fetida (one common name is red wiggler).

Most decomposers are microscopic organisms, including protozoa and bacteria. Other decomposers are big enough to see without a microscope. They include fungi along with invertebrate organisms sometimes called detritivores, which include termites and millipedes.

Worms are incredibly important decomposers in soil, meaning they break down organic matter and turn it into nutrients for plants to grow. Worms also help aerate the soil by burrowing holes for air and water to move in the soil. If there were no worms, our soils would be depleted of nutrients, drier and more compact. All of these things would make soil less suitable for plant growth, which is vital to every living thing.

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