Compost Elements

Composting is a controlled aerobic process in which bacteria, fungi, and other microorganisms convert organic material into a stable humus-like product. Since microorganisms do most of the work, you must provide the best environment for them to live. To provide the best habitat for microorganisms the following is required:

• Good carbon to nitrogen (C:N) ratio: Animal carcasses are high in nitrogen so you must add large amounts of carbon. A C:N of 20:1 to 40:1 is reasonable, the preferred range is 25:1 to 30:1.  
• Adequate moisture: Microorganisms need water to move around and transport nutrients. A moisture content of 40 to 70% is reasonable, the preferred range is 50 to 60%.  
• Good aeration: Composting is an aerobic process, which means the microorganisms need air to compost properly. Oxygen levels should be maintained above 5%.   
• Controlled temperatures: The warmer the pile, the faster the microorganisms work. Temperatures between 43-65°C (110-150°F) are acceptable, but anything above 70°C (158°F) is too hot for the microorganisms to survive. The preferred range is 54-60°C (130-140°F). For effective pathogen and weed seed kill, all material must be exposed to temperatures greater or equal to 55°C.  For in-vessel systems, the pile must reach at least 55ºC for three consecutive days; whereas, windrow systems must reach at least 55°C for 15 days and turned a minimum of five times.  
• pH Levels: Composting is effective at pH levels between 5.5 and 9. The target pH is 7. 

The above five factors in combination are the key to making microorganisms happy and working hard. If you can achieve these things, then composting will be possible.