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Multiple use can be effected in three ways:

different uses of adjacent sub-areas which together form a composite multiple use area;
the alternation in time of different uses on the same areas; and
more than one use of an area at one time.

In multiple use planning, where differing resource uses are conducted at the same time on the same area and conflicts between users will occur, one resource is determined to be the dominant use and all other secondary uses are integrated only in-so-far as they are compatible with the first. Often multiple use planning sacrifices the production of the individual resources in favour of the over-all mix of resource uses that brings the greatest social and economic benefits.

	Major culvert: a stream culvert having a pipe diameter of 2000 mm or greater, or a maximum design discharge of 6 m3/sec or greater.
	Managed forest land: forest land that is being managed under a forest management plan utilizing the science of forestry.
	Management plan: a management plan or management and working plan approved under a tree farm licence, woodlot licence, pulpwood agreement or forest licence. Contains inventory and other resource data.
	Management area: stands or forest types that require similar management practices and can be grouped for treatment as a management unit.
	Management assumptions: approximations of management objectives, priorities, constraints and other conditions needed to represent forest management actions in a forest planning model.
	Management option: a prescription of management activities over time that will achieve specified management objectives.
	Management plan: detailed long-term plan for a forested area. Contains inventory and other resource data.
	Management unit plan: the third level of planning in the Ministry of Forests hierarchical planning system. A plan prepared for a Timber Supply Area which takes into account regional goals and land use interactions. Management unit plans provide a basis for Forest Service programs. The annual allowable cut for the management unit is calculated on the basis of the management unit plan.
	Management zone: the outer portion of a riparian management area situated adjacent to a stream, lake, or wetland and established to conserve and maintain the productivity of aquatic and riparian ecosystems when harvesting is permitted.
	Map folio: a series of maps bound together, often produced as overlays of information, e.g., soils, fish, water, forest, and wildlife.
	Marine-sensitive zones: For the purposes of the Forest Practices Code of British Columbia Act Operational Planning Regulation it includes herring spawning areas, shellfish beds, march areas, aquaculture sites, juvenile salmonid rearing areas and adult salmon holding areas.
	Mass wasting: movement of soil and surface materials by gravity.
	Mature: trees or stands that are sufficiently developed to be harvestable.
	Mature timber: stands of timber where the age of the leading species in a stand is greater than the specified cutting age. Cutting ages are established to meet forest management objectives. Usually stands with lodgepole pine or a deciduous species as the leading species are classified as mature timber when the stand age is greater than 80 years. Otherwise, all stands having conifers other than lodgepole pine and whitebark pine as the leading species are mature when the stand age is greater than 120 years.
	Maximum density: the maximum allowable stand density above which stands must be spaced to a target density of well-spaced acceptable stems to achieve free-growing status.
	Mean Annual Increment (MAI): the average annual increase in volume of individual trees or stands up to the specified point in time. The MAI changes with different growth phases in a tree's life, being highest in the middle years and then slowly decreasing with age. The point at which the MAI peaks is commonly used to identify the biological maturity of the stand and its readiness for harvesting.
	Mechanical site preparation: any activity that involves the use of mechanical machinery to prepare a site for reforestation.
	Mechanized access and use: refers to access and use by, for example, mountain bikes and other bicycles, hang gliders, and other human-powered mechanized equipment. Associated facilities include aircraft landing facilities, boat docks, and heliports.
	Mechanized stand tending treatment: any stand tending activity that involves the use of mechanical machinery to treat a stand.
	Memorandum of understanding (MOU): an agreement between ministers defining the roles and responsibilities of each ministry in relation to the other or others with respect to an issue over which the ministers have concurrent jurisdiction.
	Merchantable timber: a tree or stand that has attained sufficient size, quality and/or volume to make it suitable for harvesting.
	Merchantable volume: the amount of sound wood in a single tree or stand that is suitable for marketing under given economic conditions.
	Meridian line: a north-south reference line often appearing on maps. Meridian lines are also etched into the bearing plate on a compass.
	Microclimate: generally the climate of small areas, especially insofar as this differs significantly from the general climate of the region. Stands often create microclimates.
	Microsite: a small area which exhibits localized characteristics different from the surrounding area. For example, the microsites created by a rock outcrop with thin soils, or the shaded and cooled areas created on a site by the presence of slash.
	Mineral soil: soil consisting predominately of, and having its properties determined by, inorganic matter. Usually contains less than 20 percent organic matter.
	Minimum utilization standard: included in every licence authorizing the harvesting of timber, a standard which is expressed as a maximum stump height, diameter at stump height, and top diameter and which can vary by species and timber supply area (and supply blocks within timber supply areas).
	Mixed stand: a stand composed of two or more tree species.
	Modified burning zone: a zone within or adjacent to a smoke-senstive area that requires special considerations and burning techniques, even under favourable conditions, to maintain air quality within a smoke-sensitive area.
	Monoculture: in general, even-aged, single-species forest crops.
	Mortality: death or destruction of forest trees as a result of competition, disease, insect damage, drought, wind, fire and other factors (excluding harvesting).
	Motorized access and use: refers to access and use by, for example, float planes, helicopters, fixed-wing aircraft, motorboats, motor bikes, all-terrain vehicles, snowmobiles, and motorized equipment.
	Multiple use: a system of resource use where the resources in a given land unit serve more than one user.
	Multiple Use Sustained Yield Calculation (MUSYC): a linear programming forest planning model developed by the United States Forest Service. MUSYC is currently used as the British Columbia Forest Service's standard forest planning model for carrying out TSA timber supply computer analysis.
	Mycorrhiza: a rootlet of a higher plant modified through integral association with a fungus to form a constant structure which differs from either component but is attached to the root system and functions somewhat as a rootlet. It is usually considered to be beneficial to the associated plant.