Aeration - The exhange of air in the pore spaces of the soil with the air in the atmosphere.

Aerobic - Describes organisms living or occurring only when oxygen is present.

Clay Soil - Soil made up of very fine particles. Holds water and nutrients but does not drain well and can be hard to work.

Fertilizer - A natural or manufactured material added to the soil that supplies one or more of the major nutrients - nitrogen, phosphorus and potassium - to growing plants.

Humus – A dark colored, stable form of organic matter that remains after most of the plant and animal residues in it have decomposed.

Loam – The best texture for soil to have; it contains a balance of fine clay, medium sized silt and course sand particles.

Micronutrient – A nutrient plants need in very small quantities. Micronutrients include copper, chlorine, zinc, iron, manganese, boron, and molybdenum.

Organic – Materials that are derived directly from plants or animals.

Organic Matter – An organic soil substance that contains valuable nutrients.

pH – A measure of how acid or alkaline a substance is. The pH scale ranges from 1.0 to 14.0 with 7.0 indicating neutrality, below 7.0 acidity and above 7.0 alkalinity. Most soils fall in the range from 5 to 8.

Sandy Soil – Soil that contains 50 to 70 percent Sand, 0 to 30 % Silt, 15 to 20% Clay.

Silt – Refers to a soil particle of moderate size – larger than clay but not as large as sand.

Soil Amendment – A material added to the soil to make more productive by improving its structure, drainage, microbial activity, moisture retention or aeration.

Soil Structure – The physical arrangement of soil particles and interconnected pore spaces. The ease with which soil crumbles apart or stays together – friability.

Soil Texture – The measure of percent sand, silt and clay particles in soil. Determines the class name of the soil – Loam, Sandy Loam, Clay Loam, Silty Loam etc.

Top-dress – The action of applying soil material evenly over lawn areas or a bed of growing beds.

Tilth – The structure and friability of the soil; the ease of producing a desirable seedbed from the soil.