PATCHES OF PRAIRIE – 21

         By Dr. Valerie Wright

         March 2004

Compost Happens! on the Nature Trail

You may have seen and perhaps used the public sanitary facility on the Nature Trail, known to us simply as “The Potty”. It was installed in the fall of 2001 for the convenience of our visitors. It is a composting toilet, which is environmentally safe and inexpensive to maintain. Do you know how composting happens?

            An integral part of many gardening projects is composting, or decomposition and recycling of organic wastes. Although most people think of composting in the context of gardening, the breakdown of organic matter takes place all around us as a basic part of the “carbon cycle”, where nutrients are used, transformed, taken apart and reused again by living things. Without decomposition our world would be heaped with the remains of once living things and their excretions.

            Many kinds of organisms, such as bacteria, fungi, earthworms, and arthropods, feed on the bodies of dead plants and animals and their excrement. The final product is rich, dark humus, which becomes part of the soil. Adding organic matter to the soil not only increases its nutrient value but also causes the soil to hold more water longer. The tallgrass prairie utilizes this process in forming the rich soils of the Great Plains.

            The composting option for recycling human waste utilizes all the same processes but optimizes and accelerates them. Microorganisms break down the organic material in an aerobic system. Peat moss is added to create an easily aerated compost pile and helps to maintain the proper moisture content. Aeration allows oxygen to reach the microbes inside the pile and removes CO₂. Air movement also evaporates the water, which can be up to 90 percent of the waste. The ambient temperature must be above 55 degrees F., which is why “The Potty” is closed during the cold months. Reopening it in the spring depends on warm weather.

            There are no chemicals used in a composting toilet and there is no need for pumping out a tank and finding a place to dispose of the chemical soup. With your help our composting toilet will work well for many years. Please follow the instructions given inside and enjoy using “The Potty”!