Glossary
Activator—Activators are additives to the compost pile which contain a nitrogen source or sugars. Their purpose is to increase microbial activity. Generally, adequate nitrogen organic waste is the only activator needed. If you have insufficient nitrogen, a substance like cottonseed meal may be added to encourage decomposition.
Active Composting (hot composting)—Optimum conditions for compost piles, including 30:1 Carbon-to-Nitrogen ratio, 1" or smaller particles of various sizes and textures, moisture, air, volume of 3 cubic feet, produce an environment that will attract psychrophilic, mesophyllic, and then thermophilic bacteria. As the thermophilic bacteria work, the compost pile will reach as high as 170°F. This is the fastest method of creating compost from a backyard pile, and can take as little as 3 weeks if the pile is monitored and turned each time the temperature starts to fall.
Aerobic—Containing oxygen; referring to an organism, environment, or cellular process that requires oxygen.
Ambient temperature—Air temperature.
Anaerobic—Lacking oxygen; referring to an organism, environment, or cellular process that lacks oxygen and may be poisoned by it.
Batch processing—An entire cubic-yard pile is built at the same time, and finishes decomposing at the same time. This is the opposite of the continuous or "add-as-you-go"processing. Because the entire pile is built at one time, factors such as moisture, C:N ratio, variety of textures and sizes, etc. can be more closely controlled for fast decomposition.
Biodegradable—Able to be broken into simpler chemical compounds by microorganisms. Organic materials are biodegradable.
"Browns"—The term "browns" is used to denote organic materials high in carbon, more specifically, materials whose carbon to nitrogen ratio is higher than 30:1. (Materials high in nitrogen are referred to as "greens"). Achieving a carbon-to-nitrogen ratio of about 30:1 is one factor in creating favorable conditions for backyard pile composting.
Carbon-to-nitrogen ratio (C:N)—The relative amount of carbon to nitrogen, e.g., a 2:1 ratio means that there is twice as much carbon as nitrogen. Bacteria, like all living organisms, require quite a bit of carbon and comparatively less nitrogen. By providing them with materials that provide these elements in the correct proportion, they thrive, grow, and multiply. Therefore, they can decompose your compost pile at their highest speed. Achieving a carbon-to-nitrogen ratio of about 30:1 is one factor in creating favorable conditions for backyard pile composting.
Castings—Earthworm feces;earthworm castings are high in nutrients for plants and microorganisms.
Compost—A humus or soil-like material created from aerobic, microbial decomposition of organic materials such as food scraps, yard trimmings, and manure. Compost is organic material that can be used as a soil amendment or as a medium to grow plants.
Composting—The controlled biological decomposition of organic material in the presence of air to form humus-like material. Controlled methods of composting include mechanical mixing and aerating, ventilating the materials by dropping them through a vertical series of aerated chambers, or placing the compost in piles out in the open air and mixing it or turning it periodically.
Decompose, decomposition—Decay;rot; the breaking down of organic materials into smaller particles until the original material is no longer recognizable.
“Greens”—The term "greens" is used to denote organic materials high in nitrogen, more specifically, materials whose carbon to nitrogen ratio is lower than 30:1. (Materials high in carbon are referred to as "browns"). Achieving a carbon-to-nitrogen ratio of about 30:1 is one factor in creating favorable conditions for backyard pile composting.
Landfill—Modern landfills are well-engineered facilities that are located, designed, operated, and monitored to protect the environment from contaminants which may be present in the solid waste stream. Municipal solid waste landfills (MSWLFs) receive household waste. MSWLFs can also receive non-hazardous sludge, industrial solid waste, and construction and demolition debris.
Leachate—Liquid "run-off". Leachate from the compost pile contains nutrients generated in the composting process. In contrast, as groundwater and rain flow through a landfill, they pick up weak acids created by decaying organic matter. As these acids react with other garbage, the leachate can become toxic which may contaminate streams and groundwater unless the landfill is properly constructed to contain the run-off.
Macroorganism—Living organisms in the soil which are large enough to be seen with the naked eye. Includes mite, millipede centipede, snail, slug, spider, ant, beetle, cut worm, earthworm, rodent.
Mesophilic: This group of bacteria species works to break down organic matter under "warm" conditions of 40°F up to 110°F. The ideal temperature of their environment is 70°F to 90°F.
Mulch—Covering for soil. Mulch should not generally be mixed into the soil, it is not a fertilizer or soil amendment. There are many types of mulch, including partially decomposed compost, bark, wood chips, hay, nut shells, pine needles, and others. The point is to cover bare ground so that top soil is not washed away, soil temperature is buffered, and weeds are reduced from lack of light. A good organic mulch will also supply nutrients to the earth as it decomposes.
Municipal Solid Waste (MSW)—Commonly known as trash or garbage.
Organic—Literally refers to something derived from plant or animal matter. It includes anything that is or was living, made from something living, or excreted from something living. The term "organic" also is used to describe a philosophy of working within the laws and systems existing in nature to achieve a healthy environment that is bountiful long-term. Healthy soil is the foundation of this philosophy; therefore, the term comes up frequently in discussions of home composting.
Passive Composting (cold composting)—When less attention is given to providing and maintaining optimum conditions for compost piles, the resulting environment that will attract psychrophilic bacteria, possibly mesophilic bacteria, but not thermophilic bacteria. As the psychrophilic bacteria work, the compost pile will reach about 55°F. This is the slow method of creating compost from a backyard pile, and can take as long as 6 months to 2 years to create compost. However, there is little maintenance other than occasionally turning the pile. This type of compost piles requires the least effort.
Psychrophilic—Cold-loving (e.g., microorganisms that grow best at low temperatures.) This group of bacteria species work to break down organic matter under "cold" conditions of 0°F up to over 55°F. They generate low levels of heat.
Recycling—Sorting, collecting, and processing materials to remake them into similar or dissimilar products and sell them as new products. Common examples are newspapers, glass, plastic, steel, and aluminum.
Reduction, source reduction, reduce (as part of "reduce, reuse, recycle")—Practices which result in the reduction of wastes without additional energy expended for recycling, composting, disposal, etc. Examples are: minimal packaging, lowering demand for disposable products, leaving grass clippings and leaves on the lawn, and learning to read/write/review data online without printing it onto paper.
Reuse—Practices which find alternate uses or alternate avenues for use of an item rather than expending energy to dispose it or alter its form by recycling or composting. Examples would be donating used books and magazines to a nursing home, using the fronts of greeting cards to make new cards, using plastic margarine tubs to hold leftovers or craft supplies, donating clothing to charity.
Solid waste—Any garbage or refuse, sludge from a wastewater treatment plant, water supply treatment plant, or air pollution control facility and other discarded material, including solid, liquid, semi-solid, or contained gaseous material resulting from industrial, commercial, mining, and agricultural operations, and from community activities.
Source reduction—Altering the design, manufacture, or use of products and materials to reduce the amount and toxicity of what gets thrown away.
Source separation—In homes or commercial operations, waste is separated into categories for recycling, composting, or landfilling. This is the technical term for separating your newspapers, glass, yard wastes, plastic bottles, etc. into separate containers or piles for waste processing.
Thermophilic—Heat-loving bacteria species that work to break down organic matter under "hot" conditions of 104°F up to 170°F. This type of bacteria can perform the greatest decomposition in the shortest amount of time.
Vermicomposting—Through this method, special composting worms—not nightcrawlers or field worms found in gardens—are placed in bins with organic matter in order to break it down into a high-value compost called castings.
Waste combustors—Facilities that burn MSW at a high temperature, reducing waste volume and generating electricity.
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