Compost Glossary

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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.
To aerate soil is to introduce air into the soil. This can be accomplished by many methods including plowing, roto-tilling, using a pitch fork or pole to punch holes into the earth.
A compost pile that is not turned (static), but is aerated through ventilation pipes that run through the pile. These may be PVC pipes with holes drilled into them.
Containing air, containing oxygen.
A mass or body of individual units or particles. Healthy soil has good aggregation. As microorganisms and worms feed, they form polysaccharides which act like glue to hold individual soil particles together, creating groups, or aggregates, of particles. This loose formation allows soil to hold both water and air, and does not restrict the growth of roots.
Air temperature, i.e., the temperature of the air around the pile and not affected by the heat of the pile.
Lacking air, lacking oxygen.
substances found in places such as plant sprouts and human urine which stimulates growth in plant tissues promoting root formation.

Microorganisms that break down organic materials in the first stages of composting. It is bacteria that generate the heat associated with hot composting. The three types of bacteria are psychrophilic, mesophyllic, and thermophilic.
Manure, i.e., excretions, of bats.
An entire cubic-yard pile is built at the same time, and finishes decomposing at the same time. This is the opposite of the "add as you go"method. 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.
Able to be broken into simpler chemical compounds by microorganisms. Organic materials are biodegradable.
In an environments created solely by nature, there is a variety of plant and animal life, ranging from the very small to the very large. Nature has created a natural system for post and disease control. However, when we only incorporate limited variety in our landscapes, the system of checks and balances breaks down. In general, the more diverse we can make our gardens, the healthier they will be.
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.

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.
Macroorganisms that feed on other animals. Includes ant, beetle, centipede, enchytraed, fly, mite, mole, scorpion, slug, snail, spider, springtail.
Manure, i.e., excretion, of earthworms. Earthworm castings are high in nutrients for plants and microorganisms.
In science, chemicals are elementary substances such as oxygen, hydrogen, nitrogen, etc. In the context of home composting, however, the word "chemical" is often used to describe a philosophy considered to be in opposition to the organic philosophy. In general, the chemical philosophy encourages people to force nature to do what they want by applying synthetic pesticides and fertilizers which may get the temporary results they want, but may harm or not enhance the general soil condition and environment.
Soils with clay particles and small air pores. Water retention is high creating poor drainage conditions.
Blades of grass cut off during the mowing process.
When less attention is given to providing and maintaining optimum conditions for compost piles, the resulting environment that will attract psychrophilic bacteria, possibly mesophyllic bacteria, but not thermophilic bacteria. As the psychrophilic bacteria work, the compost pile will reach about 55 degrees 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 occassionally turning the pile. This type of compost piles requires the least effort.
Compaction of soil is a lack of air or oxygen. Particles of soil are pressed together so tightly that there is insufficient air space. The obvious way this may occur is when a great weight is present, i.e., during construction when large trucks are daily rolled over the land. However, chemical overuse and poor irrigation are more common causes. In healthy soil, natural processes provide aeration, notably the presence of earthworms burrowing their way through the soil.
Completely decayed organic matter. It is dark, odorless, and rich in nutrients.
Organic compounds acting like hormones in plants. Stimulates or alters cellular RNA resulting in a modification to plant development. Generally acts by affecting cellular division and differentiation into roots and shoots. This inhibits aging in the plant.

Decay. Rot. The breaking down of organic materials into smaller particles until the original material is no longer recognizable.
Macroorganisms that eat decaying matter. Includes ant, beetle, centipede, cricket, earthworm, earwig, enchytraeid worm, millipede, mite, scorpion, slug, snail, spider, springtail, termite, woodlice.
The ground that lies directly below the outermost reaches of a trees branches.

Manure, i.e., excretion, of earthworms. Earthworm castings are high in nutrients for plants and microorganisms.

Easily crumbled. Healthy soil is friable, so if you hold up a handful of soil and wiggle your fingers the particles of soil should fall out of your hand.

Leaving grassclippings on your lawn to break down and add nutrients. You must mow a little more often so only short clippings are left on the lawn.
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.
Manure, i.e., excretions, of bats and birds. Can be purchased after being dried and composted.

Removing compost from the composting environment for use in the landscape, lawn or garden.
Macroorganisms that eat plants. Includes insect and beetle larva, grub, mouse, slug, snail, termite, woodchuck.
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 cubit 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 degrees 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.
Decomposed organic matter. Healthy soil will consist of about 3.5 to 5% of this organic matter. Humus is soft, sweet-smelling, shapeless dark and crumbly and smells like the forest floor (more correctly, the forest floor smells like humus because that is what is naturally there).

It is this stage of the decomposition process which provides nutrients for plant life. It contains about 30% each of lignin, protein, and complex sufars. It contains 3 - 5% nitrogen and 55 - 60% carbon. Humus is the slow-release food source for microorganism development. It is constantly being transformed into acids, enzymes and minerals and, therefore, must be constantly replenished for proper vegetative nutrition.

Dominant microorganisms which may be added to a compost pile. Generally, these are not necessary as there are microorganisms living on all organic matter, so your pile already has these in it.

There are currently no terms under "J".

There are currently no terms under "K".

Pleasant term for a garbage dump which is located in a cavity in the ground so that, when full, it may be covered up and look like part of the land. Today's landfills are sanitary and require special technology to eliminate methane gas and toxic leachate produced by the garbage.
An operation to excavate and process solid wastes which were previously landfilled.
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.
Lime is sometimes added to compost piles to increase pH. However, unless you are seeking a high-pH compost it is unlikely you need to add lime. Compost piles become acidic in the initial stages as organic acids are formed. However, as the composting process continues, the pH returns to a balanced state. If you add lime, an odor may occur because of the formation of ammonia gas.

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  1. ** Glossary **
  2. Calculate C : N Ratio
  3. FAQ on Composting
  4. Compost Ingredients

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