Common Earthworm Pests

Common Earthworm Pests

Earthworms need to live in a moist environment which may also attract other creatures to the bed or bin.


Centipedes are swift predators that will kill worms and need to be removed immediately. Be really careful, they will use the claws behind their heads to sting. Stingers possess poison glands that they use to paralyze small earthworms, insect larvae and small insects and spiders. Centipedes have one set of legs per segment on their bodies.


Earwigs are outdoor insects usually found under mulch, logs or dead leaves. They both need and are very attracted to moisture. Rapid runners, earwigs are easily identified by the prominent pincers on the end of the abdomen. The common earwig is a light, reddish brown flattened insect, up to one inch in length. Most species of earwigs are scavengers that feed on dead insects and decaying plant material. Some species are predators. Earwigs may try to pinch if handled carelessly, but are harmless to people.

Fruit Flies

A Fruit Fly has red eyes and a brownish colored body. They are attracted to decaying fruit and vegetable matter. Unfortunately, were there is rotting food, there are usually Fruit Flies. At least they are harmless, even if they are a nuisance. Microwave or freeze food before placing in the worm bin, as this destroys any eggs that exist in the food waste, to prevent infestations. Old fashioned, sticky fly strips work well to clear out adult Fruit Flies.

Fungus Gnats

Fungus gnats look like small reddish brown mosquitoes. They are harmless to people and earthworms. The larvae feed on fungus or plant roots. Adults attack houseplants. To reduce fungus gnat populations in your worm bin, let it dry out by keeping the lid off until the bedding dries out a bit.


Often called pill bugs, sow bugs, or roly-polies, Isopods look like tiny armadillos. They are really crustaceans with delicate gills along the abdominal surface. Isopods need to be kept moist or they will die. Isopods are vegetarians, and will not harm earthworms.

Land Planarians

Land Planarians, also called Flatworms, are iridescent slimy worms with a hammer or disk shaped head. They eat slugs, each other, and are voracious predators of earthworms. Much like slugs, they hide in dark, cool, moist areas during the day. Feeding and movement occur at night. Land Planarians are extremely destructive to earthworm populations and need to be removed and destroyed upon sight. Smashing will not destroy them, as they grow back from small pieces. Spray with orange oil or bleach, or collect to dry out in hot sun.


Millipedes are vegetarians that eat decaying plant tissue. They are harmless to earthworms. Millipedes move much more slowly than Centipedes and have a rounder body. Millipedes have two sets of legs per segment on their bodies.


Mites are the most common pests to show up in your earthworm beds or bin. Problems occur when mite population increases to high levels. See Dealing With Mites in Earthworm Beds or Bins.


Springtails are tiny, wingless insects, usually white in color. They feed on mold, fungi, bacteria and decomposing plant material so they are harmless to earthworms. Springtails can “jump” about 75 mm. They have a tiny spring-like structure under their bellies that shoots them into the air when the catch is triggered. Springtails are most numerous in wetter bedding, while numbers decrease as the bedding dries out.

White Worms

Sometimes called Pot Worms, White Worms are very small, white colored worms that reach about one quarter to one inch in length. People sometimes confuse them with baby earthworms. Higher concentrations of White Worms are likely to be found in acidic bedding. They eat dead organic material and are harmless to earthworms. White Worms are raised as food for aquarium fish.


  See our Earthworm page for our selection of domestic earthworms.  

Can you make money raising earthworms? Learn the answers to that and other questions in our 5-part article: There’s Pleasure and Profit in Raising Earthworms.


New York Worms, Long Island, New York