Common Compost Insects & Worms

You have built your compost pile of materials with the proper mix of leaves, sticks and green matter. Now is the time for the work crew to enter the area and break the components down into rich organic fertilizer. Your compost will be host to a series of common, yet important, insects, worms and larvae.


Earthworms and the smaller redworm are common residents in a compost pile. They feed on the pile's rotting foods, fungi, mold and bacteria. Vermicomposting is a form of composting that is dependent on red worms. The worms feed on the materials and pass castings, or manure, which is rich in nitrogen, phosphorous and potassium. Redworms work well for small, contained compost bins and for school science fair composting projects. Earthworms keep busy tunneling and aerating the soil while feeding on dead insects and decayed plant matter. The night crawler is a cold-soil dweller that cannot survive in the heated contents of a compost bin.

Primary Consumers

When you start a new compost pile, you will soon notice that a series of insects and worms will begin to arrive to process the materials. Primary, or first responders, consist of slugs, snails, nematodes, earthworms, whiteworms, sowbugs, millipedes and some types of mites. The nematode represents the largest population of a compost bin. Species of the microscopic worms feed on decaying vegetation. Some nematodes suck the juice from plant roots and others feed on protozoa, bacteria, fungi and other nematodes in the compost. A single rotting apple can host 90,000 nematodes, according to Cornell University Department of Crop and Soil Science. Slugs and snails feed on fresh kitchen vegetation and plants; the sowbug slowly feeds on decaying vegetation. House flies and fruit flies, also known as vinegar flies, will show up in the early stages of decomposition. They lay eggs in the organic materials. Bury the fresh vegetable and fruit matter to control the fly population.

Secondary and Tertiary Consumers

Once organic matter goes through the beginning stages of decomposition and the processing from primary consumers, additional consumers arrive on the scene. The second group to infiltrate the feeding grounds are springtails, mites, earwigs, soil flatworms and feather-winged beetles. Tertiary consumers such as carabid beetles, predatory mites, rove beetles, fomacid ants and centipedes then join the compost banquet. Secondary and tertiary consumers feed on decaying matter. Springtails feed on nematodes and other arthropods and their droppings. They also eat fungi, decomposing organic matter, grain and pollen. Some of these insects, such as the large ground or rove beetle, feed on other consumers. Feather-wing beetles eat and break down fungal spores. Spiders, pseudoscorpions and earwigs are predators that invade the compost bin to feed on compost consumers. This helps control the insect population to maintain balance in your bin.

Keywords: vermicomposting, compost bin, compost consumers

About this Author
