Metamorphosis – A basic change in form; for example, the changing of a grub to an adult beetle or caterpillar into an adult butterfly.

Microbial – Effects associated with the action or influence of microorganisms.

Microorganisms – Living plants or animals (such as bacteria, fungi, or protozoa) that are so small they can be seen only with the aid of a microscope.

Minerals – The inorganic materials that make up a portion of the soil derived from rocks; they are usually of specific composition and crystalline in form.

Mixture – As applied to turfgrasses, it is a combination of two or more plant species. For example, a mixture of Kentucky bluegrass and fine-leaved fescue seed.

Molt – To shed or cast off (such as skin, hair or feathers) followed by replacement through continued growth. Molting is often associated with the changes from immature to mature stages among the various insect groups.

Monocot (short for Monocotyledonae) – A class of seed plants distinguished by such plant features as narrow, parallel-veined leaves, fibrous root systems, seeds containing only one cotyledon (seed leaf). Grass plants are a common example.

Mowing – The periodic and usually regular cutting of a lawn area to a specified height for its intended use and function. Accomplished with mowers, either manual or power operated.

Muck – Soil-like material developed in a swamp-like environment, composed largely of well decomposed organic materials (humus).

Mulch – Non-living material used to cover the soil surface for purposes of controlling weeds, conserving moisture, reducing soil temperatures, and in some instances, improving appearance. Examples are woodchips, compost, and leaves.

Mulching Mower – Mowers specifically designed to finely chop grass clippings and forcibly direct them back into the lawn leaving a clean, uniform appearance to the surface.

Natural – The world of living things, material objects, and the forces and process which guide and shape living and nonliving things.

Natural Growth Cycle (Turf) – The sequence of grass root, shoot and flowering growth phases that occur naturally over the course of a growing season.

Natural Organic Nitrogen Fertilizer – A fertilizer product containing plant nutrients derived from various organic sources as contrasted with simpler inorganic sources. Common sources include composts, sludges, animal manures and various plant and animal processing by-products.

Net Weight (Fertilizers) – The actual weight of only the fertilizer nutrients contained in a package of fertilizer.

Nitrogen – An essential nutrient required for plant growth. It is a significant component of plant proteins. Adequate nitrogen produces good green color and vigorous plants. Shortages of nitrogen are usually indicated by yellowing leaves and poor growth. Excess nitrogen can result in unhealthy, lush growth making the plants more vulnerable to environmental stresses such as heat, drought, frost and, increased disease susceptibility. The primary communications center operated by the U.S. Coast Guard to receive reports of major chemical and oil spills and other hazardous substances into the environment. The NRC immediately relays reports to a predesignated federal On-Scene Coordinator.

Non-Selective – A term applied to a category of herbicides that does not discriminate in its effect on one type of plant over another. For example, both grasses and broadleaf plants would be injured or killed as opposed to selectively killing broadleaf plants without affecting the grasses in a lawn area.

Non-Target Organism – Plants (or other organisms) other than those attempted to be controlled by an application of a pesticide.

Noxious – Any plant declared by a state authority to be so objectionable that efforts will be directed at its eradication.

N-P-K – Chemical symbols for nitrogen (N), phosphorus (P) and potassium (K). On a container of fertilizer, these nutrients are always expressed as percentages contained in the package and are always shown in the order N-P-K.

Nutrients (Plant) – Mineral elements considered essential for plant growth. There are presently 16 minerals known to play essential roles in plant nutrition.

Nutrient Release Rate – The speed at which plant nutrients, especially N, become available for plant use following application to a lawn. This rate is often determined by the product, water and temperature conditions at the time of application.

Nymph – The immature stage between the egg and adult of some insect groups; nymphs look like the mature adult in form but do not have fully developed wings and are not able to reproduce.