text: Compost Questions and Answers 
  **What is compost?**
  Compost is a natural humus-like soil amendment that results from 
  the controlled aerobic (with oxygen) decomposition of organic 
  materials. Compost is not soil – it should be mixed with soil. It is 
  not fertilizer, although it contains many slowly released nutrients. 
  
  **What materials (“feedstocks”) are used to make compost?**
  Compost facilities in Washington recycle a variety of organic 
  materials, including yard debris, food scraps, manure, biosolids, 
  forest residuals like sawdust and bark, construction wood, and 
  agricultural residues. All of these materials can be used to produce 
  high quality compost. Your supplier can tell you which materials 
  they compost. 
  
  **How do I know I’m getting safe, quality compost?**
  Fortunately, in Washington we have strict permitting and production 
  standards for compost facilities, that include both time and 
  temperature requirements and contaminant limits. 
  
  **What about weed seeds, plant diseases or pesticide residues?**
  The controlled time, aeration, and temperature process required in 
  Washington has been shown to kill weed seeds and plant diseases. 
  That same process breaks down most pesticide residues. There are 
  a few agricultural pesticides that are not easily broken down, and 
  permitted Washington compost manufacturers carefully watch their 
  feedstocks to keep those materials out of the composting process. 