Composting is an aerobic process, which means it occurs in the presence of oxygen. Oxygen is provided in two ways:
Microorganisms need water, just like you or I. Ideally, the moisture content should be between 40 and 60 percent. Too wet, and anaerobic conditions result; too dry, and the decomposition process will slow way down.
Bacteria, fungi, and other microorganisms get their energy from carbon sources, such as leaves, brush, or wood chips. Nitrogen is required for population growth, but excess nitrogen can generate ammonia and other odors, and can pollute runoff water. If high nitrogen materials such as grass clippings are used, they must be thoroughly mixed with a carbon source. Surface area is also important in this relationship, asthe carbon in leaves is much more available than the carbon in a large wood chip.
As the microorganisms are working away, decomposing waste, they generate heat. When temperatures rise above 140° F, the organisms start to die. Turning the pile when temperatures reach this point will prevent overheating, which can result in drastic population fluctuations and odors.
Eventually, the microorganisms will use up most of the readily decomposable waste, and the composting process will slow. Temperatures drop, and the compost takes on a dark, granular texture. At this point, the compost can be placed in large stockpiles to cure, and will continue to improve until it is ready for use.
|Carbon:Nitrogen||30 : 1|
|"Fact Sheet #2, Compost Ingredients"||
||"Operator's Fact Sheets, Table of Contents"|
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This page was created on August 24, 1995
This page was last updated October 2000
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