Fungi and protozoans soon join the bacteria. Often, a white layer forms just beneath the surface of the compost. This is usually due to fungi and actinomycetes, a class of filamentous bacteria. Springtails, mites, and other small insects, as well as earthworms, also play a role in decomposition once the compost has cooled. Materials Anything growing in your yard is potential food for these microbes.
Microorganisms use the carbon in leaves or woody wastes as an energy source.
Nitrogen provides the microbes with the raw element of proteins and nucleic acids to build their bodies. This balance can be achieved by mixing. Table 1 can help you judge the ratio of your compost ingredients. Composts often are deficient in nitrogen when wood wastes are added to the mixture. This can be corrected by adding 1 pound of urea per cubic yard of compost mixture.