Compost Fundamentals

Biology & Chemistry

Organisms to Look For

A compost pile is a zoo of critters! All of the organisms, microbial and non microbial, have a dramatic effect on the soil food web. Although it is common to divide creatures into “good” and “bad” bugs, in the compost pile, every organism has a specific role to play. The larger organisms visit the pile when it has cooled down and feast on the former inhabitants. Here are just a few samples of what creatures you will find if you look closely in your pile:

Actinomycetes: Primarily decomposers common in early stages of compost. They produce the grayish cobwebby growths throughout compost and give it an earthy smell, similar to a rotting log. They prefer woody material, and survive in a wide range of temperatures.
Fungi: They are also primary decomposers. Fungi send out thin mycelia fiber like roots, far from their spore forming reproductive structures. Mushrooms are most common. They’re not as efficient as bacteria, since they can’t live in the cold.
Nematodes or roundworms: They are the most abundant invertebrates in soil. Less than one millimeter in length, they prey on bacteria, protozoa, fungal spores and each other. Most nematodes in the soil are beneficial.
Mold Mites
Fermentation mites or mold mites: These transparent bodied creatures feed primarily on yeast in fermenting masses or organic debris. They can develop into seething masses over a fermenting surface such as a winery, but are not pests in compost.
Springtail: Along with nematodes & mites, they share numerical dominance among soil invertebrates. They feed on fungi, nematodes and small bits of organic detritus. They help control fungi.
Wolf spiders: They build no webs, but run freely hunting prey. They prey on all sizes of arthropods, invertebrate animals with jointed legs and segmented bodies
Centipede: They prey on almost any type of soil invertebrate near their size or larger.
sowbugs & Pillbugs
Sow bugs: They feed on rotting woody material and leaf tissues.
Ground Beetle
Ground beetles: Most feed on other organisms but some feed on seeds and other vegetable matter.


Aerobic Decomposition

Anaerobic Fermentation

Organisms Involved

Organisms to Look For

Acid/Alkalinity Issues

Why Compost | Biology & Chemistry | Compost Needs
Composter's Needs | Benefits & Uses | Conclusion

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