Worms are soft, long, cold-blooded animals without any legs or spine. Some worms are so small you can't see them without a microscope; others grow many feet long. Most worms live in the soil. It's possible to confuse the larvae of certain insects with worms, because they look something like them when they're young. Pin-like worms found in your garden might be true worms, or they might be the larvae of beetles or flies.
Potworms or whiteworms are small, threadlike, white-segmented worms that are related to earthworms. They eat bacteria and fungus and don't damage plants. They often appear in compost piles and earthworm farms.
The larvae of fungus gnats have dark heads and threadlike white bodies that are only ¼ inch long. These wormlike creatures eat fungi and decaying organic matter. Sometimes the larvae are present in large numbers that look like "ropes" that may be several feet long.
Root maggots are only ¼ to 1/3 inch long. These small, legless yellowish or white larvae of flies have tapered or pointed heads and a blunt back end. Root maggots cause a lot of damage to vegetable crops.
Symphylans are small wormlike creatures that grow to be around ¼ inch in length. They can be white or cream-coloured; sometimes they look translucent. Their bodies are flat and segmented. They have long antennae and up to 12 legs. Garden symphylans can damage seedlings and new roots.
Wireworms, or beetle larvae, attack a variety of vegetable crops. The larvae have hard bodies and are darker than maggots. Their colour ranges from tan to copper, and their size ranges from 4/10 inch to over 1½ inches in length.