Common Compost Terms

Aerobic – having sufficient free oxygen to support respiration

Anaerobic – not having sufficient free oxygen to support respiration

“Brown” Materials – organic materials with a high carbon-to-nitrogen ratio such as dead leaves, dry hay, dry wood chips, and paper

Dripline – the ground directly below the farthest reach of a tree’s branches

Essential Plant Nutrients – elements that are necessary for the normal growth of plants

“Green” Materials – organic materials with a low carbon-to-nitrogen ratio such as green grass clippings, vegetable trimmings, and fresh manure

Macronutrients – essential plant nutrients that are used in relatively large quantities: nitrogen, phosphorus, potassium, calcium, magnesium, and sulfur

Micronutrients – essential plant nutrients that are used in very small amounts: iron, manganese, copper, zinc, boron, molybdenum, chlorine, and cobalt

Microorganism – a living thing that is only visible through a microscope

Organic – consisting of residues from living things, including dead leaves and branches, grass clippings, manure, and the products of the natural decomposition of these residues

Organism – living thing

pH – a measurement of the acidity or alkalinity of a material, on a scale from zero (maximum acidity to 14 (maximum alkalinity), with 7 representing neutral.