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  1. References preceeded by an asterisk (*) are reprinted by permission from the Society of Range Management's Rangeland Glossary A full reference to this glossary is given in the references section at the bottom of this page.
  2. References preceeded by a double-asterisk(* *) are reprinted or modified by permission from the Canada Center for Remote Sensing's Glossary of Remote Sensing Terms A full reference to this glossary is given in the references section at the bottom of this page.
  3. Pellant, M., P. Shaver, D. A. Pyke, J. E. Herrick. 2005. Interpreting indicators or rangeland health, version 4. Technical Reference 1734-6. U.S. Department of the Interior, Bureau of Land Management, National Science and Technology Center, Denver, CO. BLM/WO/ST-00/001+1734/REV05. 122pp.
  4. Keeley, J. E. 2009. Fire Intensity, fire severity, and burn severity: a brief review and suggested usage. International Journal of Wildland Fire, 18: 116-126.
  5. Virginia Department of Forestry.
  6. National Wildfire Coordinating Group (NWCG). (2012). Glossary of Wildland Fire Terminology.



Non-living components of an ecosystem; basic elements and compounds of the environment. cf. biota, biomass. 1

Absorbed Photosynthetically Active Radiation (APAR)**

Solar energy (400 - 700 nm) consumed by green canopy in the photosynthetic process.2


The total number of individuals of a species in an area, population, or community. 1


The ease with which an area can be reached by people or penetrated and grazed by animals. The ease with which herbivores can reach plants or plant parts. 1

Acclimatized Species*

An introduced species which has become adapted to a new climate or a different environment and can perpetuate itself in the community without cultural treatment. cf. exotic, introduced species. 1

Acid Equivalent*

The amount of toxicant in a pesticide expressed in terms of the parent acid or the amount that theoretically can be converted to the parent acid. Abbr. a.e. 1

Active Ingredient*

That part of a pesticidal commercial product or spray mix which directly causes pesticidal effects, often expressed in percent, weight of toxicant per unit of measure or pounds per acre. Syn., in part, with acid equivalent. Abbr. a.i. 1

Active Remote Sensing**

A remote sensing system that transmits its own electromagnetic emanations at an object(s) and then records the energy reflected or refracted back to the sensor. Radar is an example of an active system. It sends out pulses of microwaves and then receives the echo reflected from the target.2


(1) The allocation of rights or privileges following a hearing of conflicting claims either by a court or a hearing board. May refer to grazing, water, or any other rights or privileges. (2) The apportionment of grazing use on public range among eligible applicants. 1


Change in animal numbers, seasons of use, kinds or classes of animals, or management practices as warranted by specific conditions. 1

Administrative Site*

Work center or other area reserved for administrative purposes. 1

Aerial Photograph*

A photograph of the earth's surface taken from airborne equipment, sometime called aerial photo or air photograph. 1

Aerial Photography**

Photographs taken from aircraft2


Forage available after harvest. 1


(1) A descriptive term to indicate the relative age of plants. (2) Refers to age and class of animal. 1


Land use system in which woody perennials are grown for wood production with agricultural crops, with or without animal production. 1


Land use system in which woody perennials are grown with agricultural crops, forage crops, and livestock production. 1

Air-Dry Weight*

The weight of a substance after it has been allowed to dry to equilibrium with the atmosphere. 1


The ratio of the radiation reflected from an object to the total amount incident upon it, for a particular portion of the spectrum.2

Alienated Land*

Land of one ownership enclosed within boundaries of another ownership. Often refers to land in private ownership within the boundaries of public land. 1


Chemical inhibition of one organism by another. 1

Allotment Management Plan*

A long-term operating plan for a grazing allotment on public land prepared and agreed to by the permittee and appropriate agency. 1


A rangeland and/or forestland area designated for the use of a prescribed number and kind of livestock under one plan of management. cf. community allotment. 1


Sediments deposited by streams, rivers, and moving waters. 1


Describes the false error rate, the Type II error.

Alternate Stocking*

The repeated grazing and resting of forage using two paddocks in succession. 1


A device for measuring altitude2


The process of paying initial costs plus sub- sequent interest costs over a payment period, usually in equal periodic installments. 1

Animal Substitution Ratio*

A numerical ratio of numbers, units or stocking levels of one animal species to another or in partitioning grazing capacity between two animal species. Such a ratio is site-specific since it is based on a unique set of environmental, forage, animal- herbage, and animal-area variables and requires knowledge of relative animal population levels. 1

Animal Unit Conversion Factor*

A numerical figure expressing the forage requirements of a particular kind or class of animal relative to the requirement for an animal-unit. A conversion factor is satisfactory with respect to the amount of forage required to maintain an animal, but may not be applicable in determining stocking rates for range use for particular kinds or classes of animals because of different grazing preferences. 1


One day's tenure upon range by one animal. Must specify kind and class of animal. Not synonymous with animal-unit month. 1


Energy requirement of ungulate herbivores based only on animal-related factors such as body size, stage of life cycle, production stage, etc. 1


A month's tenure upon range by one animal. Must specify kind and class of animal. Not synonymous with animal-unit month. 1


Considered to be one mature cow of about 1,000 pounds (450 kg), either dry or with calf up to 6 months of age, or their equivalent, consuming about 26 pounds (12 kg) of forage/day on an oven-dry basis. Abbr. AU. cf. animal-unit-equivalent1


The forage demand (amount of forage) on an oven-dry basis required by one animal unit for a period of one day. Abbr. ADD. 1


A number relating the forage dry matter intake ( oven-dry basis) of a particular kind or class of animal relative to one AU. If intake is not known, it can be estimated from the ratio of the metabolic weight of the animal in question to the metabolic weight of one AU (450 kg to the .75 power). Abbr. AUE.1


The amount of oven-dry forage (forage demand) required by one animal unit for a standardized period of 30 animal-unit-days. Not synonymous with animal month. Abbr. AUM. The term AUM is commonly used in three ways: (a) stocking rate, as in “X acres per AUM”; (b) forage allocations, as in “X AUMs in Allotment A”; © utilization, as in “X AUMs taken from Unit B.” 1


Equal to 12 AUMs. Abbr. AUY. 1

Annual Grassland*

California annual grasslands being managed as annual range and showing no trend in successional status. 1

Annual License or Permit*

A document which specifies the total authorized grazing for one year. cf. term license or permit1

Annual Plant*

A plant that completes its life cycle and dies in 1 year or less. 1

Annual Range*

Range on which the principal forage plants are self-perpetuating annual, herbaceous species. 1


The characteristic of a surface for which a physical property, such as reflectivity, varies in value with the direction in or along which the measurement is made.2

Apical Dominance*

Domination and control of meristematic leaves or buds located on the lower stem, roots, or rhizomes by hormones produced by apical meristems located on the tips and upper branches of plants, particularly woody plants. 1

Apparent Trend*

An interpretation of trend based on observation and professional judgment at a single point in time. 1


A geologic formation capable of transmitting water through its pores at a rate sufficient for water supply purposes. The term water-bearing is sometime used synonymously with aquifer when a stratum furnishes water for a specific use. Aquifers are usually saturated sands, gravel, fractures, caverns or vesicular rock. 1

Area Ignition (Firestorm)*

The practice of simultaneous ignition of fuel over an area planned to be burned under prescription or the natural occurrence/phenomenon of the same. 1


A term applied to regions or climates where lack of sufficient moisture severely limits growth and production of vegetation. The limits of precipitation vary considerably according to temperature conditions, with an upper annual limit for cool regions of 10 inches or less and for tropical regions as much as 15 to 20 inches. cf. semiarid. 1


The term used for large gully in Southwestern USA. Syn., coulee, gully. 1


(1) The visual first impression of vegetation or a landscape at a particular time or as seen from a specific point. (2) The predominant direction of slope of the land. (3) The seasonal changes in the appearance of vegetation. 1


Syn. plant association. 1

Atmospheric Absorption**

The process whereby some or all of the energy of sound waves or electromagnetic waves is transferred to the constituents of the atmosphere.2

Atmospheric Scattering**

The random dispersion of electromagnetic radiation by particles in the atmosphere. All radiation detected by remote sensors which observe the Earth, must first pass through some distance of atmosphere. The atmosphere transmits, absorbs, and scatters the electromagnetic energy.2


Decrease in the strength of a signal. Common causes of attenuation of an electromagnetic wave include losses through absorption and scattering as the wave travels through the atmosphere.2


Abbreviation for animal-unit. 1


Abbreviation for animal-unit-month. 1


A subdivision of ecology that deals with the relationship of individuals of a species to their environment. cf. synecology. 1


Syn. cattleguard. 1


A plant hormone promoting or regulating growth.1


Abbreviation for animal-unit-year.1

Available Forage*

That portion of the forage, expressed as weight of forage per unit land area, that is accessible for consumption by a specified kind, class, sex, size, age, and physiological status of grazing animal. cf. forage allowance, forage mass. 1

Available Water*

The portion of water in a soil that can be absorbed by plant roots. 1

Azonal Soil*

A soil lacking a well-defined profile.1



Ignition of a fire on the leeward (downwind) side of a burn area, resulting in a slow moving ground fire. cf. headfiring.1


A land type consisting of steep or very steep barren land, usually broken by an intricate maze of narrow ravines, sharp crests, and pinnacles resulting from serious erosion of soft geologic materials. Most common in arid or semiarid regions. A miscellaneous land type. 1

Balanced Operation*

A range livestock enterprise which provides sufficient feed and forage resources during each season to promote continuous satisfactory maintenance and production of its livestock and game. 1

Band Ratio**

An image created by dividing the values of pixels in two different images or bands within the same image for the same area. Ratios can help accentuate subtle differences as well as minimize unwanted information. System and processing effects must be considered when producing ratios since noise can be increased; noise should always be reduced before producing a ratio image. Ratio images must be scaled to produce an acceptable product for visual interpretation. Interpreting ratio images requires a knowledge of target reflectance illumination and ground conditions. Examples of ratio images include vegetation indices (NDVI, VI) and mineral colour composites. Using Landsat TM data, you can determine areas of iron oxide concentration using band 3/band 1, clay minerals using band 5/band 7, and ferrous minerals using band 5/band 4.2


Any number of sheep handled as a unit attended by a herder. cf. consolidated, drop, dry band, flock. 1


A selection of wavelengths recorded by a sensor2


Tenure by a band of sheep of a given size and class for one day. 1

Bare Ground*

All land surface not covered by vegetation, rock or litter. cf. ground cover1


(1) (n.) Any area devoid of vegetation or practically so. (2) (adj.) A term to describe a mature female animal which is incapable of producing offspring. 1


A physical obstruction which limits the movement of animals. 1

Basal Area*

The cross sectional area of the stem or stems of a plant or of all plants in a stand. Herbaceous and small woody plants are measured at or near the ground level; larger woody plants are measured at breast or other designated height.1

Basal Cover*

Syn. basal area, cover. 1

Base Map**

Fundamental map information used as a standard framework upon which additional map data are created.2

Base Property*

Those lands in a ranching enterprise which are owned or under long-term control of the operator.  1

Bed Ground*

An area where animals sleep and rest. 1


In-place, solid rock exposed at the surface of the earth or overlain by unconsolidated material. 1

Bench Mark*

(1) A permanent reference point. (2) In range inventory, it is used as a point where changes in vegetation through time are measured. (3) In soils, it is used to designate a major soil series which is representative of similar soils. (4) In economics, data that are used as a base for comparative purposes with similar data. (5) A surveyor's mark made on a permanent landmark that has known position and attitude. 1


A natural clay deposit which has high swelling capabilities when saturated; used to seal earthen stockponds.  1


A plant that lives for two years, producing vegetative growth the first year and usually blooming and fruiting in the second year and then dying. 1


A chemical toxic or lethal to living organisms. 1


Capable of being decomposed by natural processes. 1

Biogeochemical Cycle*

The cyclical system through which a given chemical element is transferred between biotic and abiotic components of the biosphere. 1


The total amount of living plants and animals above and below ground in an area at a given time. 1


A major biotic unit consisting of plant and animal communities having similarities in form and environmental conditions, but not including the abiotic portion of the environment. 1


All the species of plants and animals occurring within an area or region. 1


Refers to living components of an ecosystem, e.g., plants and animals. 1


A group of individuals within a population occurring in nature, all with essentially the same genetic constitution. A species usually consists of many biotypes. cf. ecotype. 1

BLM Grazing Allotment

The Bureau of Land Management (BLM) issues 2,400 grazing authorizations including permits, leases, and exchange-of-use agreements annually. The allotment refers to the tract of land administered by the BLM that is authorized to be grazed by a private party. An electronic Rangeland Administration System (RAS) is used to streamline the award process. The database is available to the public at


(1) An excavation in areas of loose soil, usually sand, produced by wind. (2) A breakthrough or rupture of a soil surface attributable to hydraulic pressure, usually associated with sand boils. 1


(1) (v.) To mark the skin or wool of an animal in a distinctive pattern, by use of a hot or cold iron, chemical, paint, or other means to designate ownership or to identify individual animals for registration or management purposes. cf. marking, tagging. (2) (n.) The mark so made.  1

Breeding Herd*

The animals retained for breeding purposes to provide for the perpetuation of the herd or band. Excludes animals being prepared for market.  1

Broadcast Seeding*

Process of scattering seed on the surface of the soil prior to natural or artificial means of covering the seed with soil. cf. drill seeding. 1

Browse Line*

A well-defined height to which browse has been removed by animals. cf. highlining. 1


(n.) The part of shrubs, woody vines and trees available for animal consumption. (v.) To search for or consume browse. 1


A lane built through a dense brushland or brush thicket to provide access by herbivores and man and/or to encourage browse rejuvenation. cf. sendero. 1

Brush Control*

Reduction of unwanted woody plants through fire, chemicals, mechanical methods, or biological means to achieve desired land management goals. 1

Brush Management*

Manipulating woody plant cover to obtain desired quantities and types of woody cover and/or to reduce competition with herbaceous understory vegetation, in accordance with ecologically sound resource management objectives. 1


A term encompassing various species of shrubs or small trees usually considered undesirable for livestock or timber management. The same species may have value for browse, wildlife habitat, or watershed protection. 1


An area covered primarily with brush, i.e., shrubland.1


A fence constructed of wooden poles fastened horizontally to wooden cross-members. Such fences withstand heavy snows in mountainous regions, and eliminate the need for digging holes for posts in rocky terrain. Also called buck-pole fence.  1

Bucking Range*

In certain localities, range selected for placing rams with ewes.  1

Buffalo Wallow*

A small natural depression of prairie occasionally containing standing water and having vegetation different from that of the surrounding area. 1

Bunch Grass*

A grass having the characteristic growth habit of forming a bunch; lacking stolens or rhizomes. cf. sod grass. 1


An area over which fire has recently passed. 1

Burn Severity

Also referred to as fire severity, burn severity is a measure of the loss of organic matter both above and below ground. 4


An isolated hill with relatively steep sides. cf. mesa. 1

Burn Severity

Aboveground and belowground organic matter consumption from fire. Sometimes subdivided into 'vegetation burn severity' and 'soil burn severity'.4


C-3 Plant*

A plant employing the pentose phosphate path- way of carbon dioxide assimilation during photosynthesis; often a cool-season plant. 1

C-4 Plant*

A plant employing the dicarboxylic acid pathway of carbon dioxide assimilation during photosynthesis; often a warm season plant. 1


The use of a large cable pulled between two large crawler tractors to pull down or uproot brush. cf. chaining. 1


A spiny, succulent plant of the Cactaceae family. 1

Calf Crop*

The number of calves weaned from a given number of cows exposed to breeding, usually expressed in percent, i.e., number of calves weaned + number of cows exposed x 100 = percent calf crop. cf. kid crop, lamb crop.  1


( 1) A layer in the soil horizon more or less cemented by secondary carbonates of calcium or magnesium precipitated from the soil solution. It may occur as a soft, thin soil horizon, as a hard, thick bed just beneath the solum, or as a surface layer exposed by erosion. Not a geologic deposit. (2) Alluvium cemented with sodium nitrate, chloride, and/or other soluble salts as in the nitrate deposits of Chile and Peru. 1

Camp Tender*

One who transports supplies to a herder and moves the supply camp from place to place on the range. 1

Camp Unit*

A subdivision of a sheep allotment on federally owned land. The camp tender may have the camp in one location several days to service the herder, who tents on a different bed ground each night with the camp unit. 1

Canopy Cover*

The percentage of ground covered by a vertical projection of the outermost perimeter of the natural spread of foliage of plants. Small openings within the canopy are included. It may exceed 100%. Syn. crown cover.1


(1) The vertical projection downward of the aerial portion of vegetation, usually expressed as a percent of the ground so occupied. (2) The aerial portion of the overstory vegetation. cf. canopy cover.1

Capability Area*

Syn. ecological response unit 1

Carrying Capacity*

The average number of livestock and/or wildlife that may be sustained on a management unit compatible with management objectives for the unit. In addition to site characteristics, it is a function of management goals and management intensity. 1

Catchment Basin*

Syn. raintrap. 1

Cattle Walkway*

Syn. walkway.1


A device or structure, at points where roads or railroads cross a fence line, that is so designed that vehicular travel is uninterrupted but crossing by all kinds of livestock is restricted. Syn. autogate.  1


A grazing arrangement comprised of numerous sub- divisions (paddocks or pastures) often formed by electrical fencing, with a central component to facilitate livestock management and movement to the various sub-divisions. Normally used to facilitate a form of controlled grazing. cf. paddock. 1


The use of a large ship anchor chain pulled between two large crawler tractors to pull down or uproot brush. cf. cabling. 1

Change Detection**

The sensing of environmental changes that uses two or more scenes covering the same geographic area acquired over a period of time. Change detection is useful for monitoring: urbanization, agricultural development, forest land management, ice forecasting, etc. The most widely used methods are: Difference Image, Ratio Image, Classification Comparison, and Change Vector Analysis.2

Change Vector Analysis**

A method of change detection that uses spectral or spatial differences to detect a change or disturbance.2


(1) A shrub community composed of sclerophyllous species. (2) A dense thicket of stiff or thorny shrubs or dwarf trees. 1


Breaking or loosening the soil, without inversion, with a chisel cultivator or chisel plow. A practice used for grassland or pasture renovation. cf. ripping. 1

Class of Animal*

Description of age and/or sex-group for a particular kind of animal. Example, cow, calf, yearling, ewe, doe, fawn, etc. 1

Classification Accuracy**

The extent to which a manual or automatic processing system correctly identifies selected classes.2


The assignment of items or concepts into classes based on similarity of selected attributes.1


A dense compact layer in the subsoil having a much higher clay content than the overlaying material from which it is separated by a sharply defined boundary; formed by downward movement of clay or by synthesis of clay in place during soil formation. Claypans are usually hard when dry and plastic and sticky when wet. They usually impede the movement of water and air. cf. hardpan. 1


The average or prevailing weather conditions of a place over a period of years. 1


(1) The final or stable biotic community in a successional series; it is self-perpetuating and in equilibrium with the physical habitat. 1


A group of plants, growing in close association, derived by asexual reproduction from a single parent plant. Such plants are therefore of the same genetic constitution. 1

Close Herding*

Handling a herd in a closely bunched manner, restricting the natural spread of the animals when grazing. 1

Closed Area*

Any area closed to certain types of use for management purposes. 1

Closed Range*

Any range on which livestock grazing or other specified use is prohibited. cf. livestock exclusion. 1

Cold Stratification*

Keeping seed in a cool, moist environment for a period of time to simulate overwintering thereby reducing dormancy and increasing seed germination. 1

Color Infrared (CIR)**

(1) Digital imagery that includes bands from the color and near infrared wavelengths. (2) A false colour film different from ordinary colour film in that the three sensitized layers are sensitive to green, red and infrared radiation instead of blue, green and red. A multi emulsion film at least one of whose emulsions is sensitive to infrared radiation.2


Capacity of a permittee's base ranch property to support permitted livestock during the period such livestock are off public land.  1

Commensurate Property*

Land or controlled livestock water which qualifies a person for a grazing privilege, permit, or 1

Common Use*

Grazing the current year's forage production by more than one kind of grazing animal either at the same time or at different seasons. cf. dual use. 1

Community (Plant Community)*

An assemblage of plants occurring together at any point in time, while denoting no particular successional status. A unit of vegetation. 1

Community Allotment*

An allotment upon which several permittees graze livestock in common. 1

Community Type*

An aggregation of all plant communities with similar structure and floristic composition. A unit of vegetation within a classification with no particular successional status implied. 1


A general term for an assemblage of plants and/or animals living together and interacting among themselves in a specific location; no particular successional status is implied. 1

Companion Crop*

A crop sown with another crop (perennial forage or trees or shrubs) that is allowed to mature and provide a return in the first year. cf. nurse crop. 1

Comparison Area*

An area with a documented history and/or condition that is used as a standard for comparison. 1


The interaction between organisms as a result of the removal or reduction of a common, required resource from the environment. Resources may include water, nutrients, light, oxygen, carbon dioxide, food and shelter. 1

Complementary Pasture*

Short-term forage crop (not necessarily annual) planted for use by domestic stock to enhance the management and productivity of the ranch.  1

Complete Protection*

The exclusion of all grazing animals from an area, usually for an extended period of time. 1


Syn. species composition 1

Concentrate Feed*

Grains or their products and other processed food materials that contain a high proportion of nutrients and are low in fiber and water.  1

Confusion Matrix**

see: Error Matrix2

Conservation District*

A public organization created under state enabling law as a special-purpose district to develop and carry out a program of a soil, water, and related resource conservation, use, and development within its boundaries. Usually a subdivision of state government with a local governing body and always with limited authorities. Often called a soil conservation district or a soil and water conservation district. 1

Conservation Plan*

The recorded decisions of a landowner or operator, cooperating with a conservation district, on how he/she plans, within practical limits, to use his/her land according to its capability and to treat it according to its needs for maintenance or improvement of the soil, water, and plant resources. 1


The use and management of natural resources according to principles that assure their sustained economic and/or social benefits without impairment of environmental quality. 1

Consolidated Band*

A band of sheep made up of several small bands.  1


The percentage occurrence of a species within a given community type. 1

Consumer's Accuracy**

It is a measure of the reliability of an output map generated from a classification scheme. It is a statistic that can tell the user of the map what percentage of a class corresponds to the ground-truthed class. Consumer's accuracy is calculated by dividing the number of correct pixels for a class by the total pixels assigned to that class.2


Heterotrophic organisms, chiefly animals, that ingest other organisms or particulate organic matter. 1


Dietary intake based on (1) amounts of specific forages and other feedstuffs, or (2) amounts of specific nutrients. 1

Contact Herbicide*

A herbicide that kills primarily by contact with plant tissue rather than as a result of translocation.1

Continuous Grazing*

The grazing of a specific unit by livestock throughout a year or for that part of the year during which grazing is feasible. The term is not necessarily synonymous with yearlong grazing, since seasonal grazing may be involved. A preferred term is continuous stocking. 1

Continuous Stocking*

A method of grazing livestock on a specific unit of land where animals have unrestricted and uninterrupted access throughout the time period when grazing is allowed. The length of the grazing period should be defined. cf. rotational stocking, set stocking. 1

Contour Furrow*

A plowed or listed strip, commonly 8 to 18 inches deep and wide, made parallel to the horizontal contour for the purpose of water retention and reduction of soil erosion. 1

Control (1) [PLANT] Manipulation and management for reduction of noxious plants, a term of many degrees ranging from slightly limiting to nearly complete replacement*

(2) [RESEARCH] Term to designate the standard or no treatment in an experiment in order to evaluate treatment responses. 1

Controlled Burning*

Syn. prescribed burning. 1

Conversion Factor*

A factor by which stocking rates are partitioned according to the kind or class of animal based on energy requirements. cf. animal-unit. 1

Cool-Season Plant*

A plant which generally makes the major portion of its growth during the late fall, winter, and early spring. Cool-season species generally exhibit the C3 photosynthetic pathway. cf. warm-season plant. 1

Coordinated Resource Management Planning*

The process whereby various user groups are involved in discussion of alternate resource uses and collectively diagnose management problems, establish goals and objectives, and evaluate multiple use resource management. 1


A small enclosure for handling livestock.  1


The term used for a deep gulch or ravine in the northern USA. 1

Cover Type*

The existing vegetation of an area. 1


(1) The plant or plant parts, living or dead, on the surface of the ground. Vegetative cover or herbage cover is composed of living plants and litter cover of dead parts of plants. Syn. foliar cover. (2) The area of ground covered by plants of one or more species. cf. basal area. 1

Creep Feeding*

Supplemental feeding of suckling livestock in such a manner that the feed is not available to the mothers or other mature livestock. 1

Creep Grazing*

The practice of allowing juvenile animals to graze areas that their dams cannot access at the same time.  1

Critical Area*

An area which must be treated with special consideration because of inherent site factors, size, location, condition, values, or significant potential conflicts among uses. 1


Land devoted to the production of cultivated crops. May be used to produce forage crops. cf. forage crop. 1


A plant in any of the groups Thallophytes, Bryophytes, and Pteridiophytes-mosses, lichens, and ferns. 1

Cultivar (derived from cultivated variety)*

A named variety selected within a plant species. Distinguished by any morphological, physiological, cytological, or chemical characteristics. A variety of plant produced and maintained by cultivation which is genetically retained through subsequent generations. 1

Cumulative Herbage Disappearance*

The amount of herbage that disappears from the standing crop because of grazing, senescence, or other causes over some period of time. Unit: kg/ha, lbs./ herbage disappearance rate. 1

Cured Forage*

Forage, either standing or harvested, that has been naturally or artificially dried and preserved for future use. cf. stockpiling. 1


(1) (v.) To separate one or more animals from the herd or band. (n.) The animal(s) so separated. (2) To reduce livestock grazing, particularly on a public land allotment . 1


(1) Animals refused by a buyer because of failure to meet specifications. (2) Animals removed from a higher to a lower classification in sorting for a specific purpose. 1



Abbreviation of diameter at breast height of a tree. 1

Death Loss*

The number of animals in a herd that die from various natural and accidental causes. Usually expressed as a percentage. 1


Accumulated plant and animal remains. 1

Deciduous (Plant)*

Plant parts, particularly leaves, that are shed at regular intervals, or at a given stage of development, i.e. a deciduous plant regularly loses or sheds its leaves. cf. evergreen. 1


Heterotrophic organisms, chiefly the microorganisms, that break down the bodies of dead animals or parts of dead plants and absorb some of the decomposition products while releasing similar compounds usable by producers. 1


For a given plant community, those species that decrease in amount as a result of a specific abiotic/biotic influence or management practice. 1


The delay of grazing to achieve a specific management objective. A strategy aimed at providing time for plant reproduction, establishment of new plants, restoration of plant vigor, a return to environmental conditions appropriate for grazing, or the accumulation of forage for later use. cf. deferred grazing, rotational deferred. 1

Deferred Grazing*

The deferment of grazing in a non-systematic rotation with other land units. cf. deferment. 1


Any grazing system, which provides for a systematic rotation of the deferment among pastures. 1


The removal of plant leaves, i.e., by grazing or browsing, cutting, chemical defoliant, or natural phenomena such as hail, fire, or frost. 1

Degree of Use*

The proportion of current year's forage production that is consumed and/or destroyed by grazing animals. May refer either to a single species or the vegetation as a whole. Syn. use. 1


Numbers of individuals or stems per unit area. Density does not equate to any kind of cover measurement. 1

Dependent Property*

Property generally associated with other lands for year-round livestock operation. cf. commensurate property. 1


Land on which the vegetation is absent or sparse, often shrubby, and characterized by an arid climate. 1


The process by which an area or region becomes more arid through loss of soil and vegetative cover. The process is often accelerated by excessive continuous overstocking and drought. 1

Desirable Plant Species*

Species which contribute positively to the management objectives. 1

Desired Plant Community*

Of the several plant communities that may occupy a site, the one that has been identified through a management plan to best meet the plan's objectives for the site. It must protect the site as a minimum. 1


Fragmented particulate organic matter derived from the decomposition of debris. 1

Dietary Essentials (Nutrient)*

Nutrients that must be orally ingested, in contrast to those which can be manufactured or converted in the animal, such as through microbial symbiosis in the rumen. 1

Difference Vegetation Index (DVI)**

A vegetation index obtained by subtracting the red reflectance from the near-infrared reflectance. It is proportional to NDVI. DVI is simpler than NDVI but is prone to measurement errors in the NIR and red because it is not normalized by their sum.2

Differential GPS**

A GPS system that broadcasts corrected positions from a reference station. DGPS positions are accurate to less than 10m. The reference station is equipped with a high-quality GPS receiver, transmitter, and an antenna at a known, surveyed location. In-coming GPS signals are corrected and are then broadcasted locally on selected FM frequencies. The accuracy of the corrected positions can be as high as 1-5m, though it does decrease with increasing radial distance. Geostationary satellites are planned to broadcast wide-area DGPS corrections coverage.2

Digital Elevation Model**

A representation of the topography of the Earth in digital format, that is, by raster pixels that have real-world coordinates and numerical descriptions of altitude.2

Digital Number (DN)**

A number, between zero and 255 for example, assigned to each pixel in each band of an image representing that pixel's brightness for that band.2

Digital Terrain Model**

A representation of a surface's topography stored in a numerical format. Each pixel is has been assigned coordinates and an altitude. Digital Elevation Model (DEM) is the preferred term.2

Dipping Vat*

A trough made of concrete, wood, or metal for holding solutions in which animals are dipped. 1


(v.) Immersing animals in specific solutions to control insects or disease. 1


The process of determining the present value of a stream of future financial returns. 1


Active during daylight hours. 1


The distribution and abundance of different plants and animal communities within an area. 1


(v.) To surgically shorten an animal's tail.1


Syn. orphan. 1


(1) Plant species or species groups, which by means of their number, coverage, or size, have considerable influence or control upon the conditions of existence of associated species. (2) Those individual animals which, by their aggressive behavior or otherwise, determine the behavior of one or more animals resulting in the establishment of a social hierarchy. 1


(1) Animals composing the rear of a moving herd. (2) An implement used for control of vegetation, e.g., chain drag. 1


A natural watercourse, including the channel and adjacent areas on either side, which may occasionally overflow or receive extra water from higher adjacent areas; generally having intermittent flows associated with higher intensity rainfall. 1


(v.) Giving orally a forced dose of a specific solution to an animal, usually to control internal parasites. 1

Drift Fence*

An open-ended fence used to retard or alter the natural movement of livestock; generally used in connection with natural barriers. 1


(v.) (1) The movement of materials by wind or water. (2) the natural movement of animals. (n.) Vegetative material moved and deposited by wind and water. cf. spray drift. 1

Drill Seeding*

Planting seed directly into the soil with a drill in rows, usually 6 to 24 inches apart. cf. broadcast seeding. 1

Drip Torch*

Portable equipment for applying flammable liquids giving a residual flame upon ignition; primarily used in prescribed burning. 1


The moving of livestock under human direction. In cowboy parlance, the term drift is often used in lieu of drive when animals are slowly urged in a certain direction. 1


A strip of land specifically designated for the controlled movement of livestock. 1

Drop Band*

A band of ewes that is giving birth or is expected to give birth within a few days. 1

Drouth (Drought)*

(1) A prolonged chronic shortage of water, as compared to the norm, often associated with high temperatures and winds during spring, summer and fall. (2) A period without precipitation during which the soil water content is reduced to such an extent that plants suffer from lack of water. 1

Dry Band*

A band of ewes without lambs. 1

Dry Meadow*

A meadow dominated by grasses which is characterized by soils which become moderately dry by mid-summer. cf. meadow and wet meadow. 1

Dual Use*

Grazing the current year's forage production by two species of grazing animals at the same time. cf. common use. 1


(1) An artificially constructed depression that collects and stores water and differs from a reservoir in that a dam is not relied upon to impound water. cf. stock pond. (2) A large hole dug in the ground, frequently on the side of a hill, and often covered with logs and sod, used as a dwelling or shelter. 1


Ear Marking*

The process of removing parts of the ears of livestock so as to leave a distinctive pattern for the purpose of designating ownership and identification. 1


Establishment and development of a plant in the community. 1

Ecological Response Unit*

A unit of land that is homogenous in character such that similar units will respond in the same way to disturbance or manipulation. Syn. ecological site, ecological type. 1

Ecological Site*

A kind of land with specific physical characteristics which differs from other kinds of land in its ability to produce distinctive kinds and amounts of vegetation and in its response to management. Apparently synonymous with ecological type used by USFS. 1

Ecological Type*

Syn. of ecological site. 1


The study of the interrelationships of organisms with their environment. 1

Economic Enterprise*

Syn. economic ranch firm. 1

Economic Ranch Firm*

A ranch business of sufficient earning capacity to provide an accepted standard of living for a family. Syn. economic enterprise. 1


Organisms together with their abiotic environment, forming an interacting system, inhabiting an identifiable space. 1


A transition area of vegetation between two communities, having characteristics of both kinds of neighboring vegetation as well as characteristics of its own. Varies in width depending on site and climatic factors. cf. edge effect. 1


A locally adapted population within a species which has certain genetically determined characteristics; interbreeding between ecotypes is not restricted. cf. biotype.1


Refers to the soil. 1

Edge Detection**

Computer process to define boundaries on remote sensing imagery.2

Edge Effect*

(1) The influence of one adjoining plant community upon the margin of another affecting the com- position and density of the populations. cf. ecotone. (2) The effect executed by adjoining communities on the population structure within the margin zone. (3) The attraction of such an area to animals. 1

Edge Matching**

The process of eliminating locational and content discrepancies in the representation of features at the edges of adjacent map sheets or tiles when joining them into one coverage.2


The boundary of an object in a photograph or image, usually characterized by a rather drastic change in the gray shade value from the immediate interior of the boundary to the immediate exterior of the boundary.2

Effective Precipitation*

That portion of total precipitation that becomes available for plant growth. It does not include precipitation lost to deep percolation below the root zone or to surface runoff or to evaporation or which falls during the dormant season unless stored in soil for later use during the growing season. 1

Effective Rainfall*

Syn. effective precipitation. 1

Electromagnetic Spectrum (EMS)**

The total range of wavelengths or frequencies of electromagnetic radiation, extending from the longest radio waves to the shortest known cosmic rays.2

Emergency Feeding*

Supplying feed to range animals when available forage is insufficient because of heavy storms, fires or other such emergencies. cf. maintenance feeding, supplemental feeding. 1


An area fenced to confine animals. 1


Native to or restricted to a particular area, region or country. 1

Energy Budget*

The balance of energy input and utilization within an organism, community, or system. 1


The sum of all external conditions that affect an organism or community to influence its development or existence. 1

Environmental Information System (EIS)**

The computerized storage and manipulation of environmental data. This data may include a large proportion of geographical (spatial) information along with data specific to the description of plants, animals and their habitats. EIS are frequently derived from GIS.2


The bending or twisting of twigs or leaf petiole or blades; often used in diagnosis of herbicidal effects on plants. 1

Eradication (plant)*

Complete kill or removal of a noxious plant from an area, including all plant structures capable of sexual or vegetative reproduction. 1


(v.) Detachment and movement of soil or rock fragments by water, wind, ice, or gravity. (n.) The land surface worn away by running water, wind, ice, or other geo- logical agents, including such processes as gravitational creep. 1

Error Matrix**

A matrix or table that displays statistics for assessing image classification accuracy by showing the degree of misclassification among classes. The error matrix is also known as a confusion matrix, a contingency table or a classified error matrix. The error matrix is a means of comparing two thematic datasets (either two maps or a map and a set of ground-verified locations coded to the same thematic classes as the map). This is typically done in a tabular or array form. In remote sensing image analysis, the two thematic maps are often a “ground truth” map (the reference map) and a map derived from automated image classification (the classified map). The error matrix permits the calculation of a range of measures that describes the accuracy of the classified map with respect to the reference map. To generate the error matrix, thematic information is recorded from sample pixels that display the same ground area on the two maps. Calibration data are recorded from the reference map and validation data from the classified map.

Errors of Commission**

Pixels incorrectly assigned to a particular class that actually belong in other classes.2

Errors of Omission**

Pixels incorrectly excluded from a particular class.2


A steep slope or ridge, terminating high lands abruptly, which was formed by erosion or by faulting. 1


A device used for maintenance and closure of an esophageal fistula. 1


A permanent, surgically established opening in the esophagus of an animal used for collecting diet samples. cf. esophageal-cannula. 1

Essential Element*

A chemical element which is necessary for the life of an organism. 1


The actual total loss of water by evaporation from soil, water bodies, and transpiration from vegetation, over a given area with time. 1

Evergreen (plant)*

A plant that has leaves all year round, and generally sheds them in a single season after new leaves of the current growing season have matured. cf. deciduous. 1


An area fenced to exclude animals. 1


The process of eliminating waste material from the body. 1

Exempt Stock*

Livestock which are permitted to graze on federal land free of charge. Usually confined to animals actually used for domestic purposes: saddle horses, milk cows, etc. 1


An organism or species which is not native to the region in which it is found. 1


Direction of slope with respect to points of a compass. 1

Extensive Grazing Management*

Grazing management that utilizes relatively large land areas per animal and a relatively low level of labor, resources, or capital. cf. intensive grazing management. 1

Extent (scale)*

The maximum area under consideration with an observation. Extent coupled with grain define the scale of an observation 1


False Color Composite**

An image produced by displaying multiple spectral bands as colours different from the spectal range they were taken in. By assigning three of the image bands to the fundamental colours red, blue and green, you can produce a colour image. The blue band in the original image is often affected by atmospheric effects such as haze, and is therefore usually left out. When the assigned image bands do not correspond to the frequencies of red, blue and green the output image will appear in colours that are not intuitive or natural. For instance, different types of vegetation might appear as blue, red, green or yellow. Intuitively, vegetation would appear green. Such an image is known as a false colour composite. It is useful for extraction information difficult to discern in the original imagery, variations in vegetation species or health, for example.2

False Color**

Using one colour to represent another. A colour imaging process which produces an image of a colour that does not correspond to the true colour of the scene (as seen by our eyes).2

Fattening Range*

Range devoted primarily to fattening of livestock for market. archaic. 1


The animal life of a region. A listing of animal species of a region. 1

Feces (Faeces)*

Waste material voided through the anus. 1

Feed Ground*

A designated place on a range where livestock are fed. 1

Feed Reserve*

Feed stored for future use. cf. forage reserve. 1


(n.) Any non-injurious, edible material having nutritive value when ingested (v.) The act of providing feed to animals. 1


Escaped from cultivation or domestication and existing in the wild. cf. acclimatized species. 1

Fibrous Root System*

A plant root system having a large number of small, finely divided, widely spreading roots, but no large taproots. Typified by grass root system. cf. taproot system. 1

Field of View**

The area or solid angle which can be viewed through an optical instrument2


A natural or man-made barrier used to prevent or retard the spread of fire, that is in existence or made before a fire occurs. It is usually created by the removal of vegetation. cf. fireline, fuelbreak. 1

Fire Front

The part of a fire within which continuous flaming combustion is taking place. Unless otherwise specified, the fire front is assumed to be the leading edge of the fire perimeter. In ground fires, the fire front may be mainly smoldering combustion. 6

Fire Intensity

The amount of energy released by a fire. Fire intensity can be measured in terms of reaction intensity, fireline intensity, temperature, heating duration, or radiant energy. 4


A narrow line, 2 to 10 feet wide, from which all vegetation is removed by soil sterilization, yearly maintenance, treatment with a suitable fire retardant, or clearing just before ignition of a prescribed burn. 1

Fireline Intensity

The product of the available heat of combustion per unit of ground and the rate of spread of the fire, interpreted as the heat released per unit of time for each unit length of fire edge. The primary unit is Btu per second per foot (Btu/sec/ft) of fire front; The rate of heat release per unit time per unit length of fire front. Numerically, it is the product of the heat yield, the quantity of fuel consumed in the fire front, and the rate of spread. 6

First-last grazing*

A method of utilizing two or more groups of animals, usually with different nutritional requirements, to graze sequentially on the same land area. Syn. leader-follower; preference-follower; top and bottom grazing. 1


Characteristics of a management plan which allow it to accommodate changing conditions. 1

Flight Path**

The path taken through the air by an aircraft, satellite, or other platform. Also known as Line of Flight.2

Image source: Canada Center for Remote Sensing


A group of sheep managed in fenced pastures and not herded. cf. band. 1


(1) The plant species of an area. (2) A simple list of plant species or a taxonomic manual.1


Improving the nutrition of female breeding animals prior to and during the breeding season to stimulate ovulation. 1


Pertaining to or produced by the action of a stream or river. 1

Fly Camp*

A secondary division of a main camp, generally more temporary than the central establishment. archaic. 1


The green or live leaves of plants; mass leaves, leafage. 1

Foliar Cover*

The percentage of ground covered by the vertical projection of the aerial portion of plants. Small openings in the canopy and intraspecific overlap are excluded. Foliar cover is always less than canopy cover; either may exceed 100%. Syn. Cover.1

Forage Accumulation*

The increase in forage mass per unit area over a specified period of time. This definition can be appropriately altered to be specific to herbage or browse by substituting these terms in place of forage. 1

Forage Allocation*

The planning process or act of apportioning available forage among various kinds of animals, e.g., elk and cattle. 1

Forage Allowance*

The relationship between the weight of forage dry matter per unit area and the number of animal units at anyone point in time; a forage-to-animal relationship. The inverse of grazing pressure. May be expressed as forage mass per animal unit (forage mass/animal unit at a specific time). This definition can be appropriately altered to be specific to herbage or browse by substituting these terms in place of forage. 1

Forage Crop*

A crop of cultivated plants or plant parts, other than separated grain, produced to be grazed or harvested for use as feed for animals. 1

Forage Inventory*

An estimate of available forage in each pasture and for the operating unit as a whole; used to project stocking rates and feed requirements for specific time periods (i.e., annually, grazing season, rotation cycle, etc.). cf. grazing inventory. 1

Forage Mass*

The total dry weight of forage per unit area of land, usually above ground level and at a defined reference level. This definition can be appropriately altered to be specific to herbage or browse by substituting these terms in place of forage. cf. available forage, herbage. 1

Forage Production*

The weight of forage that is produced within a designated period of time on a given area. The weight may be expressed as either green, air-dry, or oven-dry. The term may also be modified as to time of production such as annual, current year's, or seasonal forage production. 1

Forage Reserve*

Standing forage specifically maintained for future or emergency use. 1

Forage Use Factor*

An index to the grazing use that may be made for forage species that will maintain economically important forage species or to achieve other management objectives. 1


(n.) Browse and herbage which is available and may provide food for grazing animals or be harvested for feeding. (v.) To search for or consume forage. cf. (v.) browse, graze. 1


Any broad-leafed herbaceous plant other than those in the Poaceae, Cyperaceae and Juncaceae families. cf. legume. 1

Forest Grazing*

The use of forestland or woodland for both wood production and animal production by grazing.1

Forested Range*

Forestland that produces, at least periodically, sufficient understory vegetation suitable for forage and that can be grazed without significantly impairing wood production and other forest values. Syn. grazable woodland, woodland range. 1


Land on which the vegetation is dominated by trees or, if trees are lacking, the land shows historic evidence of former forest and has not been converted to other uses. 1

Forward Creep*

A method of creep grazing in which dams and offspring rotate through a series of paddocks with offspring as first grazers and dams as last grazers. A specific form of first-last grazing. cf. first-last grazing. 1

Fraction of Photosynthetically Active Radiation (fPAR)**

Fraction of Photosynthetically Active Radiation absorbed by a vegetation canopy.2

Free Range*

Range open to grazing regardless of ownership and without payment of fees. Not to be confused with open range. 1


Ability to roam or forage at will, unrestricted by fences. cf. open herding. 1


The ratio between the number of sample units that contain a species and the total number of sample units. 1

Fresh Mulch*

The primary layer of bulky, coarse, largely un-decayed herbage residuum. cf. mulch and humic mulch. 1

Fresh Weight*

The weight of plant materials at the time of harvest. Syn. green weight.1

Frontal Grazing*

A grazing method that allocated forage within a land area by means of a sliding fence that livestock can advance to gain access to ungrazed forage. 1


All the dead and living material that will burn. This includes grasses, dead branches and pine needles on the ground, as well as standing live and dead trees. Also included are minerals near the surface such as coal that will burn during a fire, and human-built structures.5


A strategically located block or strip on which existing flammable vegetation has been replaced by vegetation of lower fuel volume and/or flammability and subsequently maintained as an aid to fire control. cf. fireline. 1

Full Use*

The maximum use during a grazing season that can be made of range forage under a given grazing program without inducing a downward trend in range condition or successional status. 1

Fuzzy Logic**

A classification method that simulates the vagueness or uncertainty encountered in nature. It categorizes data according to non-discrete class struture; the belonging of an object to a class becomes a matter of degree.2


Game Cropping*

Use of game animals in a wild state through harvesting them to keep populations in check and to reduce extreme cycles in numbers. 1

Game Ranching*

Use of game animals under semi-domestication to control breeding, health, nutrition, and production as a ranch-based enterprise. 1

Game Range*

Range that is predominantly grazed or browsed by wildlife seasonally or year around. Especially pertinent with migratory big game herds, e.g., winter elk or deer range. 1

Game Refuge*

An area set aside as a sanctuary for game. 1


(1) Wild birds, fish, and other animals taken for sport or for use as food. (2) Wildlife species so designated by law and the harvest of which is regulated by law. cf. wildlife.1

Geographic Information System (GIS)*

A spatial type of information management system which provides for the entry, storage, mani-pulation, retrieval, and display of spatially oriented data. 1

Geostationary Orbit**

An orbit around the Earth whereby a satellite travels in the same direction and completes the orbit in the same time as the Earth completes a revolution. Hence, the satellite maintains a fixed position relative to the surface of the Earth. Communication and meteorological satellites are often placed in geostationary orbit since it is easier to transmit and receive radio signals from a satellite that stays in the same relative place in the sky, than from a satellite without a fixed location. Remote sensing satellites that are required to cover most of the Earth’s surface have to use non-geostationary orbits.2

Image source: Canada Center for Remote Sensing

Geosynchronous Orbit**

An orbit around the Earth whereby a satellite travels in a general west-to-east direction and completes the orbit in the same time as the Earth completes a revolution. A geosynchronous orbit has a period which is equal to the rotation of the Earth about its axis. It will have an altitude of approximately 35,800 kilometres in order to achieve that period. The orbit can persist above the equatorial line or have an inclination to the equatorial plane. In the later case, the orbit still maintains the same orbital period as the revolution of the Earth, but spends equal time north and south of the equator, tracing a figure eight relative to a point on the Earth’s surface (Graphic 1). The “geostationary” orbit is a special case of the geosynchronous orbit. It has a zero inclination to the equatorial plane, thus staying persistently over the equator and achieving no relative motion to the Earth’s surface.2

Image source: Canada Center for Remote Sensing

Global Positioning System (GPS)**

A satellite-based radio-navigation system comprised of a constellation of twenty-four satellites and their supporting ground stations, used to obtain precise positions of targets on, or near, the surface of the Earth.2

Image source: Canada Center for Remote Sensing


(1) In livestock breeding, an offspring resulting from mating a purebred with a non-purebred or from mating animals not purebred but having close purebred ancestors. (2) In livestock marketing, a classification based on three fundamentals-conformation, finish, and quality-such as prime, choice, good, standard, etc. (3) To evaluate live animals in relation to a standard of quality. 1

Grain (scale)

The finest level of observable detail. Grain coupled with extent makes up the scale of an observation. In an image, grain is often synonymous with pixels. 1


Grass or grass-like plant, such as Poa, Carex and Juncus species. 1


Members of the plant family Poaceae. 1


Land on which the vegetation is dominated by grasses, grass like plants, and/or forbs (cf. dominant). Lands not presently grassland that were originally or could become grassland through natural succession may be classified as potential natural grassland. 1

Grass-like Plant*

A plant of the Cyperaceae or Juncaceae families which vegetatively resembles a true grass of the Poaceae family. 1

Gravel, Cobble, Stones*

As defined in Soil Taxonomy (Soil Conservation Service 1975): Gravel (2 mm-7.5 cm or 3 inches), cobble (7.5-25 cm; 3-10 inches), stones (over 25 cm; 10 inches ). (Note: For standard range inventory procedures it is recommended that gravel smaller that 5 mm in diameter be classed as bare ground in cover determinations.) 1

Grazable Forestland*

Forestland on which the understory includes, as an integral part of the forest plant community, plants that can be grazed without detrimental impact to other forest values. Syn. grazable woodland, woodland range, forest range.1

Grazable Woodland*

Forestland on which the understory includes as an integral part of the forest plant community, plants that can be grazed without detrimental impact to other forest values. Syn. grazable forestland, forested range, woodland range. 1


(1) (vi.) The consumption of standing forage by livestock or wildlife. (2) (vt.) To put livestock to feed on standing forage. 1


A grazing animal. 1


A person who manages grazing animals.1

Grazing Animal Concentration Index*

The inverse of the grazing fraction, i.e., (1/GF). Abbr. GACI. 1

Grazing Behavior*

The foraging response elicited from a herbivore by its interaction with its surrounding environment. 1

Grazing Capacity*

The maximum stocking rate that will achieve a target level of animal performance, in a specified grazing method, based on total nutrient resources available, including harvested roughages and concentrates, that can be applied over a defined period without deterioration of the ecosystem. A description of the grazing capacity should include stocking rate, grazing method, targeted animal performance and non-grazed nutrient resources. 1

Grazing Cycle*

The time elapsed between the beginning of one grazing period and the beginning of the next grazing period in the same paddock where the forage is regularly grazed and rested. One grazing cycle includes one grazing period plus one rest period. 1

Grazing Distribution*

Dispersion of livestock grazing within a management unit or area.1

Grazing District*

(1) An administrative unit of Federal range established by the Secretary of Interior under the provisions of the Taylor Grazing Act of 1934, as amended. (2) An administrative unit of state, private, or other rangelands, established under certain state laws. 1

Grazing Event*

The length of time that an animal grazes without stopping. cf. grazing period. 1

Grazing Fee*

A charge, usually on a monthly basis, for grazing use by a given kind of animal. 1

Grazing Fraction*

The fraction of land in a single grazing system which is being grazed at any time. Abbr. GF. cf. grazing animal concentration index. 1

Grazing License or Permit*

Official written permission to graze a specific number, kind, and class of livestock for a specified period on a defined allotment or management area. cf. annual, temporary and term license or permit. 1

Grazing Management Plan*

A program of action designed to secure the best practicable use of the forage resources with grazing or browsing animals. 1

Grazing Management Unit*

The grazing land area used to support a group of grazing animals for a grazing season. It may be a single area or it may have a number of subdivisions. cf. paddock, pasture. 1

Grazing Management*

The manipulation of animal grazing in pursuit of a defined objective. 1

Grazing Method*

A defined procedure or technique of grazing management designed to achieve a specific objective(s). One or more grazing methods can be utilized within a grazing system. 1

Grazing Period*

The length of time that grazing livestock or wildlife occupy a specific land area. cf. grazing event. 1

Grazing Permit*

Syn. grazing license. 1

Grazing Preference*

(1) Selection of certain plants, or plant parts, over others by grazing animals. (2) In the administration of public lands, a basis upon which permits and licenses are issued for grazing use. cf. palatability, grazing privilege and grazing right. 1

Grazing Pressure Index*

An animal to forage relationship measured in terms of animal units per unit weight of forage over a period of time, i.e., AU/kg or ton. 1

Grazing Pressure*

An animal to forage relationship measured in terms of animal units per unit weight of forage at any instant, i.e., AU/kg or ton. 1

Grazing Privilege*

Permissive use of lands for grazing by livestock. cf. grazing right. 1

Grazing Right*

A right to graze specified lands, permanently vested in the beneficiary as specified by the terms of the law or contract. 1

Grazing Season*

(1) The time period during which grazing can normally be practiced each year or portion of each year. (2) On U.S. public lands, an established period for which grazing permits are issued. It may be the whole year or a very short time span, and is normally a function of forage mass and climate. In this context, the vegetative growing season may be only a part of the grazing season. 1

Grazing Survey*

The systematic collection of data pertaining to forage resources and other information pertinent to range management. May be either extensive or intensive grazing survey. cf. range survey, forage inventory. 1

Grazing System*

A specialization of grazing management which defines the periods of grazing and non-grazing. Descriptive common names may be used; however, the first usage of a grazing system name in a publication should be followed by a description using a standard format. This format should consist of at least the following: the number of pastures (or units); number of herds; length of grazing periods; length of non-grazing periods for any given unit in the system followed by an abbreviation of the unit of time used. cf. deferred grazing, deferred-rotation, rotation, rest-rotation, and short duration grazing. 1

Grazing Trespass*

The grazing of livestock on a range area without proper authority, and resulting from a willful or negligent act. cf. unauthorized use. 1

Grazing Unit*

An area of land, public or private, which is grazed as an entity. 1


(vt.) To graze. 1

Grazingland Management*

The manipulation of the soil- plant-animal complex of the grazing land in pursuit of a desired result. The definition may be applied to specific kinds of grazing land by substituting the appropriate term, such as grassland in place of grazing land. 1


Any vegetated land that is grazed or that has the potential to be grazed by animals. 1


The difference between normalized near infrared (0.7-1.1 microns) and visible (0.5-0.7 microns) radiances of vegetation representing the state of growth of a crop.2

Ground Control**

A system of points with positions and/or elevations established by ground surveys and used in positioning and correlating map features.2

Ground Cover*

The percentage of material, other than bare ground, covering the land surface. It may include live and standing dead vegetation, litter, cobble, gravel, stones and bedrock. Ground cover plus bare ground would total 100 percent. 1

Ground Datum*

A point on the earth's surface used as reference for measuring the height of aerial photography and for calculating photo scale. 1

Ground Reflectance**

The ratio of the intensity of reflected radiation from the ground surface to that of the radiation incident on the ground surface.2

Ground Resolution**

(1) the real-world dimensions of a single pixel from an image. (2) a measure of the resolving power of a sensor when expressed as cycles per unit length on the ground from a given altitude.2

Ground Truth*

Measurements or observations made on the ground for the purpose of verifying interpretations made from aerial photography or remote sensing. 1

Ground Truth**

Information acquired by field study for the purpose of calibration and/or verification of remotely sensed data.2

Ground Water*

Subsurface water that is in the zone of saturation. The top surface of the ground water is the “water table.” Source of water for wells, seepage, springs. 1

Growing Season*

In temperate climates, that portion of the year when temperature and moisture permit plant growth. In tropical climates it is determined by availability of moisture. 1

Growth Form*

The characteristic shape or appearance of an organism. 1

Growth Regulator*

An organic substance effective in minute amounts for controlling or modifying plant processes. 1


The act of removing roots, whether woody or herbaceous, by man or animal. 1


A furrow, channel or miniature valley, usually with steep sides through which water commonly flows during and immediately after rains or snow melt. cf. arroyo and coulee. 1


A device for collecting and storing precipitation for use by wildlife or livestock. Usually, consists of an impenetrable water collecting area, a storage facility and a trough from which animals can drink. Syn. raintrap, catchment basin. cf. trick tank. 1


Habitat Type*

The collective area which one plant association occupies or will come to occupy as succession advances. The habitat type is defined and described on the basis of the vegetation and its associated environment. The concept was developed by Rexford Daubenmire. Habitat type is similar in concept to ecological site. The difference depends mainly on how specifically plant associations are defined. Habitat type is often misused to refer to classification of vegetation or wildlife habitat rather than a land classification. 1


The natural abode of a plant or animal, including all biotic, climatic, and edaphic factors affecting life. 1


A perennial plant with a woody base whose annually produced stems die each year. 1

Hard Seed*

A physiological condition of seed in which some viable seeds do not immediately absorb water or oxygen and germination is delayed when a favorable environment is provided. Non-synonymous with seed dormancy.1


The ability to survive exposure to adverse conditions. 1


A hardened soil layer in the lower A or in the B horizon caused by cementation of soil particles with organic matter or with materials such as silica, sesquioxides, or calcium carbonate. The hardness does not change appreciably with changes in moisture content, and pieces of the hard layer do not crumble in water. cf. caliche. 1


Removal of animal or vegetation products from an area of land. 1


Ignition of a fire on the windward (upwind) side of a burn area, resulting in a fairly rapid moving fire. cf. backfiring. 1

Heavy Grazing*

A comparative term which indicates that the stocking rate of a pasture is relatively greater than that of other pastures. Often erroneously used to mean overuse. cf. light and moderate grazing. 1


A term used to describe the appearance of woody plants that have been repeatedly browsed so as to appear artificially clipped. 1


The persistent browsing of terminal buds of browse species causing excessive lateral branching and a reduction in main stem growth.1


Any flowering plant except those developing persistent woody stems above ground. 1


Non-woody plant growth. 1

Herbage Allowance*

Weight of forage available per unit animal on the land at any instant. 1

Herbage Disappearance Rate*

The rate per unit area at which herbage leaves the standing crop due to grazing, senescence or other causes. Unit: kg/ha/d, or lbs/ac/d. 1

Herbage Growth Rate*

The rate of addition of new mass per unit area to the standing crop. Unit: kg/ha/d or lb/ac/d. 1


The aboveground material of any herbaceous plant. 1


A phytotoxic chemical used for killing or inhibiting the growth of plants. 1


An animal that subsists principally or entirely on plants or plant materials. 1


An assemblage of animals usually of the same species. 1


One who tends livestock on a range. Usually applied to the person herding a band of sheep or goats. 1


The handling or tending of a herd. cf. close, open and trail herding. 1


Syn. browse line.1

Historical Climax*

The plant community considered to best typify the potential plant community of an ecological site prior to the advent of European man. May no longer be one of the potential plant communities for the site. 1

Holding Ground*

An area where livestock are often held during roundups. 1

Holistic Management*

Holistic Management is a practical, goal-oriented approach to the management of the ecosystem including the human, financial and biological resources. Holistic Management entails the use of a management model which incorporates a holistic view of land, people and other resources. Holistic Management is now the correct name for the approach formerly called Holistic Resource Management.1

Home Range*

The area over which an animal normally travels in search of food. 1

Humic Mulch*

Decayed and fragmented residuum of fresh mulch. cf. mulch, humus. 1


The organic fraction of soil in which decomposition is so far advanced that its original form is not distinguishable. 1

Hurdle System*

A term sometimes applied to the method of handling sheep by means of a wolf-proof fence. archaic. 1

Hybrid Vigor*

The increased performance (rate of gain) associated with Fl crossbreeding.1


Offspring of a cross between genetically dissimilar individuals. 1


Ice-Cream Species*

An exceptionally palatable species sought and grazed frequently by livestock or game animals. Such species are often over utilized under proper grazing. 1

Illumination Angle**

The angle at which incident electromagnetic waves, more significantly those in the visible and infrared bands, strike the surface of an object. Illumination angle affects the degree of shadowing in an image.2


The amount of light energy a surface recieves per unit area2

Image Classification**

Grouping image pixels into categories or classes to produce a thematic representation. Classification can be used in thematic maps or can be further incorporated into digital analysis. It can be performed on single or multiple image channels to separate areas according to their different scattering or spectral characteristics. Digital image classification procedures are differentiated as being either supervised or unsupervised (clustering).2

Image Correction**

The adjustment of an image for errors: geometric, radiometric, etc…2

Image Differencing**

An image created by subtracting the mean value of parcels of pixels in two different images of the same area. This operation results in either a positive or a negative value where change has occurred. Zero values indicate parcels where no change has occurred. When interpreting difference images, you must consider the threshold boundaries between change and no-change.2

Image Interpretation**

Study of images for the purpose of identifying and judging the significance of selected features.2

Image Processing**

Encompasses all the various operations which can be applied to photographic or image data. These include, but are not limited to image compression, image restoration, image enhancement, preprocessing, quantization, spatial filtering and other image pattern recognition techniques.2

Image Registration**

Matching of points on two or more different images overlapped to correspond with ground points. The process of geometrically aligning two or more sets of image data such that resolution cells for a single ground area can be digitally or visually superposed. Data being registered may be of the same type, from very different kinds of sensors, or collected at different times.2

Image Resolution**

Size of the smallest detail identifiable on an image. See also Spatial Resolution, Ground Resolution2


(1) The counterpart of an object produced by the reflection or refraction of light when focused by a lens or mirror. (2) The recorded representation (commonly as a photo-image) of an object produced by optical, electro-optical, optical mechanical, or electronic means. It is generally used when the electromagnetic radiation is emitted or reflected from a scene is not directly recorded on film. For radar, the image tones represent the radar reflectivity of the scene.2


For a given plant community, those species that increase in amount as a result of a specific abiotic/biotic influence or management practice. 1

Indian Allotment*

Land held under the Indian Allotment Act of 1910, either patented or held in trust for an Indian by the government. 1

Indicator Species*

(1) Species that indicate the presence of certain environmental conditions, seral stages, or previous treatment. (2) One or more plant species selected to indicate a certain level of grazing use. cf. key species. 1


Born, growing, or produced naturally (native) in an area, region, or country. cf. endemic. 1


Invasion by large numbers of parasites or pests. 1

Infiltration Rate*

Maximum rate at which soil under specified conditions can absorb rain or shallow impounded water, expressed in quantity of water absorbed by the soil per unit of time, e.g., inches/hour. 1

Infiltration Velocity*

The actual rate at which water enters the soil at any given time. It may be less than infiltration rate because of limited supply of water. Expressed in same units as infiltration rates. 1


The flow of a fluid into a substance through pores of small openings. It connotes flow into a substance in contradistinction to the word percolation. 1


Nutritive materials consumed by the animal.1

Instantaneous Field of View**

For scanning sensors (e.g., Landsat), it is the field of view of the scanner with the scan motion stopped. When expressed in linear or area units such as meters or hectares, it is an altitude dependent measure of the ground resolution of the sensor. When expressed in degrees or radians, this is the smallest angle over which an instrument is sensitive to radiation. 2

Intensity, Hue and Saturation (HIS) Colour Space**

A system of producing colour imagery that is adapted to human vision. Intensity is the colour brightness, hue is the actual colour and saturation defines the purity or “greyness” of the colour. The IHS colour space can be represented by a cone. The intensity is measured along the vertical or height axis where 0% is black, the apex of the cone, and 100% is white, the center of the base of the cone. Hue is measured along the circumference of the base of the colour cone by degree. For example, red is 0°, yellow is 60°, green is 120°, cyan is 180°, and blue is 240°. Saturation is measured along the horizontal axis, the radius of the cone. No colour, 0%, is a point at the center of the cone and full colour, 100%, is a point on the circumference of the base of the cone.2

Intensive Grazing Management*

Grazing management that attempts to increase production or utilization per unit area or production per animal through a relative increase in stocking rates, forage utilization, labor, resources, or capital. Intensive grazing management is not synonymous with rotation grazing. Grazing management can be intensified by using any one or more of a number of grazing methods that use relatively more labor or capital resources. cf. extensive grazing management. 1

Intermittent Grazing*

A method that imposed grazing for indefinite periods at irregular intervals. 1


Interpolation refers to a process of estimating the value or size of something at unknown locations based on measurements taken from surrounding points. Interpolation can be used to estimate continuous variables like precipitation, percent shrub cover, or temperature from a set of sample points. (ESRI 2006)


Seeding into an established vegetation cover. Often is planting seeds into the center of narrow seedbed strips of variable spacing and prepared by mechanical or chemical methods. 1

Introduced Species*

A species not a part of the original fauna or flora of the area in question. cf. native and resident species. 1


Plant species that were absent in undisturbed portions of the original vegetation of a specific range site and will invade or increase following disturbance or continued heavy grazing. cf. increaser.1


The migration of organisms from one area to another area and their establishment in the latter. cf. ecesis. 1

Isolated Land*

Land of one ownership enclosed within boundaries of another ownership. Often refers to land in private ownership within the boundaries of public land.1



Kappa Coefficient**

A statistical measure of the agreement, beyond chance, between two maps (e.g. output map of classification and ground-truthed map). It is represented by the symbol kappa hat or k hat. Correctly assigned pixels may have been assigned by chance and not based on the classification decision rule. The kappa value indicates how accurate the classification output is after this chance, or random, portion has been accounted for.2


Surface composed of blocks of limestone separated by narrow fissures. archaic. 1


A limestone plateau marked by sinks, or karst holes, interspersed with abrupt ridges and irregular protuberant rocks; usually underlain by caverns and underground streams. archaic. 1

Key Area*

A relatively small portion of a range selected because of its location, use or grazing value as a monitoring point for grazing use. It is assumed that key areas, if properly selected, will reflect the overall acceptability of current grazing management over the range. 1

Key Management Species*

Plant species on which management of a specific unit is based. 1

Key Species*

(1) Forage species whose use serves as an indicator to the degree of use of associated species. (2) Those species which must, because of their importance, be considered in the management program. 1

Kid Crop*

The number of kids produced by a given number of does, usually expressed in percent kids weaned of does exposed. cf. calf crop, lamb crop. 1

Kid House*

A small structure designed to give shelter to a newborn kid. The doe is staked so that she cannot abandon the kid. 1

Kind of Animal*

An animal species or species group such as sheep, cattle, goats, deer, horses, elk, antelope, etc. cf. class of animal. 1


Kriging is a method of using the observed values at sample locations to make predictions at unsampled locations. Kriging takes advantage of the first rule of geography - that things close together are more similar than things that are far apart. It is one of a series of spatial statistical techniques that depends on samples being related to each other in space - in other words samples are not independent. Predictions can be made via kriging with only field data, but it is commonly used in conjunction with remote-sensing data in a proceedure called Regression Kriging. Kriging


Lamb Crop*

The number of lambs produced by a given number of ewes, usually expressed in percent of lambs weaned of ewes exposed. cf. calf crop, kid crop. 1

Lambing Ground*

Range reserved for grazing during lambing period. 1

Land Capability*

Land capability, as originally used in the United States, is an expression of the effect of physical land conditions, including climate, on the total suitability for use without damage for crops that require regular tillage, for grazing, for woodland, and for wildlife. Land capability involves consideration of (1) the risks of land damage from erosion and other causes and (2) the difficulties in land use owing to physical land characteristics, including climate. 1

Land Use Incentives*

A method for implementing land use plans in which a governmental unit offers inducements, usually monetary, to private landowners for adopting certain land uses or practices. 1

Land Use Planning*

The process by which decisions are made on future land uses over extended time periods that are deemed to best serve the general welfare. Decision-making authorities on land uses are usually vested in state and local governmental units, but citizen participation in the planning process is essential for proper understanding and implementation, usually through zoning ordinances. 1


The total natural and cultural environment within which production takes place; a broader term than soil. In addition to soil, its attributes include other physical conditions, such as mineral deposits, climate, and water supply; location in relation to centers of commerce, populations, and other land; the size of the individual tracts or holdings; and existing plant cover, works of improvement, and the like. Some use the term loosely in other senses; as defined above but without the economic or cultural criteria; especially in the expression “natural land”; as a synonym for “soil”; for the solid surface of the earth; and also for earthly surface formations, especially in geomorphological expression “land form.” 1


The relative degree of toxicity of pesticides to warm-blooded animals defined as the single dosage by mouth that kills 50 percent of test animals, expressed as mg/kg of body weight. 1

Leaf Area Index (LAI)*

The ratio of the total upper leaf surface of the plant community to the corresponding ground area expressed as a proportion. LAI may exceed 1. 1

Leaf Area Index (LAI)**

Ratio of green leaf area per unit soil area. Leaf Area Index is an important parameter used in remote sensing to quantify many biological and physical processes such as primary productivity, plant respiration, transpiration, photosynthesis and nutrient cycles. LAI can also help in identifying land features such as areas that have been affected by forest fires or deforestation. Leaf area index (LAI) is defined as half the total leaf area per unit ground surface area. More specifically, for broad leaf trees such as aspen or maple, it is the one-sided leaf area while for coniferous trees such as jack pine and black spruce, it is half the total needle area. For example, LAI = 3 indicates that if all the leaves or needles were removed from the trees and laid flat on the ground, they would cover 3 times the ground area above which the leaves were growing. Hence, on these satellite images of LAI, areas with LAI = 0 are usually roads or lakes.2


Members of the plant family Fabaceae. 1


One who has specified rights or privileges under lease. Syn. permittee. 1


One who leases specified rights or privileges. 1


See grazing license or permit. 1


Characteristic form or appearance of a species at maturity, e.g., tree, shrub, herb, etc.1

Light Detection and Ranging (LiDAR)**

LIDAR is an active remote sensing system that uses a LASER light beam (instead of a microwave radar beam as used in RADAR) to measure vertical distance.2

Light Grazing*

A comparative term which indicates that the stocking rate of one pasture is relatively less than that of other pastures. Often erroneously used to mean under use. cf. heavy and moderate grazing. 1


(1) Calcium oxide. (2) All limestone-derived materials applied to neutralize acid soils.1

Limiting Factor*

Any environmental factor which exists at suboptimal level and thereby prevents an organism from reaching its full biotic potential. 1


A double-wing plow, the shares of which throw the soil in opposite directions, leaving the land with a series of alternate ridges and furrows. Lister bottoms are commonly used to open a furrow for interseeding native range. 1


The uppermost layer of organic debris on the soil surface; essentially the freshly fallen or slightly decomposed vegetal material. 1

Livestock Exclusion*

Range that is closed to grazing by livestock. Syn. closed range. 1

Livestock Flexibility*

The ability to alter the number, kind, or class of animals within a livestock enterprise as warranted by variability in forage, economic, weather, or other conditions. 1

Livestock Management*

Application of technical principles and business methods to livestock production. 1

Livestock Production*

(1) The weight, number of animals, etc, that a particular range, seeded pasture, or management system produces. (2) The business of producing livestock. 1


Domestic animals. 1


Maintenance Burning*

The use of prescribed burning to maintain vegetation in a desired condition. 1

Maintenance Feeding*

Supplying feed to range animals when available forge is too limited to meet their minimum daily requirement. Usually necessitated by overuse or inclement weather. cf. emergency feeding and supplemental feeding. 1

Management Area*

An area for which a single management plan is developed and applied. 1

Management Objective*

The objectives for which range- land and rangeland resources are managed which includes specified uses accompanied by a description of the desired vegetation and the expected products and/or values. 1

Management Plan*

A program of action designed to reach a given set of objectives. cf. grazing management plan. 1

Management Site Potential*

The kinds or levels of productivity or values of a range site that can be achieved under various management prescriptions. 1

Management Unit*

A subdivision of a management area. 1

Map Scale**

The ratio of distances on a map to the actual distances they represent.2

Marginal Land*

Land of questionable physical or economic capabilities for sustaining a specific use. 1


(1) A colored or otherwise marked sheep in a range band. (2) Dye, foam, or paper strips to indicate area covered in earlier pass of sprayer. (3) An infertile (vasectomized) male animal, often equipped with a dye marker, used to identify ovulating females for artificial insemination. 1


Any method, other than branding, of placing a sign on an animal for the purpose of identification. For example: ear slits, tags, wattles, etc. cf. brand, earmarking and tagging. 1

Marsh (land)*

Flat, wet, treeless land usually covered by water and dominated by marsh grasses, indigenous rushes, sedges, or other grass-like plants. 1


Fruits and seed of shrubs, woody vines, trees, cacti, and other non-herbaceous vegetation available for animal consumption. 1

Mature Soil*

A soil with well developed characteristics produced by the natural processes of soil formation, and in equilibrium with its environment. cf. soil. 1


A tract of grassland where productivity of indigenous or introduced forage is modified due to characteristics of the landscape position or hydrology. May be characterized as: hay meadow, native meadow, mountain meadow, wet meadow, or other designations. cf. grassland, pasture, pastureland, rangeland. 1


A flat-topped mountain or other elevation bounded on at least one side by a steep cliff. Local in Southwest. 1


Ancillary data characterizing a data set (i.e. date of production, instrument type, etc.).2


One that moves from place to place. Syn. nomadic. 1

Minimum Detectable Difference (MDD)

The smallest amount of change detected between years for a single plot. This is an absolute term; if the desired detectability of change is from 10 to 15 percent, the MDD=0.05.

Mixed Grazing*

Grazing by two or more species of grazing animals on the same land unit, not necessarily at the same time but within the same grazing season. 1

Mixed Pixel**

Those pixels having a signature representative of more than one class (as with boundary pixels) or pixels saturated by strong reflectance or emittance of a sub-pixel size feature.2

Mob Grazing*

In the management of a grazing unit, grazing by a relatively large number of animals at a high stocking density for a short time period. 1

Moderate Grazing*

A comparative term which indicates that the stocking rate of a pasture is between the rates of other pastures. Often erroneously used to mean proper use. cf. heavy and light grazing. 1


The orderly collection, analysis, and interpretation of resource data to evaluate progress toward meeting management objectives. This process must be conducted over time in order to determine whether or not management objectives are being met. 1


The form and structure of an organism, with special emphasis on external features. 1


An assemblage of overlapping aerial or space photographs or images whose edges have been matched to form a continuous pictorial representation of a portion of the earth surface.2


Variation of coloration in soils as represented by localized spots, patches, or blotches of contrasting color. Commonly develops under alternating wet and dry periods with associated reduction and oxidation environments. Mottling generally indicates poor aeration and impeded drainage. 1


(n.) (1) A layer of dead plant material on the soil surface. cf. fresh and humic mulch. (2) An artificial layer of material such as paper or plastic on the soil surface. (v.) Cultural practice of placing rock, straw, asphalt, plastic or other material on the soil's surface as a surface cover. 1

Multiple Use*

Use of range for more than one purpose, i.e., grazing of livestock, wildlife production, recreation, watershed and timber production. Not necessarily the combination of uses that will yield the highest economic return or greatest unit output. Syn. multiple land use. 1

Multispectral Camera/Imager**

Camera or imaging system, which is capable of taking two or more images of a scene simultaneously, each image being taken in a different spectral band.2

Multitemporal Imagery**

A collection of images of the same area, obtained at different times.2



A single point, or locus of points on the surface of the Earth directly below a sensor as it progresses along its line of flight.2

Native Species*

A species which is part of the original fauna or flora of the area in question. Syn. Indigenous cf. introduced and resident species. 1

Natural Pasture*

Syn. range. One U.S. technical agency defines this term as formerly forested land that has been allowed to revert to native forage species and is managed primarily for production of native plants for grazing. 1

Natural Potential*

Occasionally used as a synonym for climax with reference to range vegetation. 1

Naturalized Species*

A species not native to an area but which adapted to that area and has established a stable or expanding population. Does not require artificial inputs for survival and reproduction. Examples: cheatgrass, Kentucky bluegrass, starling, etc. 1

Near Infrared (NIR)**

Infrared radiation extending approximately from 0.7 to 1.3 micrometers and being part of the radiative infrared.2

Net Primary Production*

The net increase in plant biomass within a specified area and time interval, i.e. primary production minus that used in metabolic processes. 1


The ecological role of a species in a community. 1


Pertaining to the habit of wandering from place to place, usually within a well-defined territory. Syn. migrant.1

Non-Selective Grazing*

Utilization of forage by grazing animals so that all forage species and/or all plants within a species are grazed. cf. mob grazing. Non-selective grazing is generally attempted by using high stocking rates or high stocking densities during short time periods. In practice, non-selective grazing is achieved rarely. 1


(1) Absence of grazing use on current year's forage production. (2) Lack of exercise, temporarily, of a grazing privilege on grazing lands. (3) An authorization to refrain, temporarily, from placing livestock on public ranges without loss of preference for future consideration. 1

Normalized Difference Vegetation Index (NDVI)**

An index calculated from reflectances measured in the visible and near infrared channels. It is related to the fraction of photosynthetically active radiation.2

Noxious Species*

A plant species that is undesirable because it conflicts, restricts, or otherwise causes problems under management objectives. Not to be confused with species declared noxious by laws concerned with plants that are weedy in cultivated crops and on range. 1

Nurse Crop*

A temporary crop seeded at or near the time primary plant species are seeded to provide protection and otherwise help to insure establishment of the latter. cf. companion crop, preparatory crop. 1


Any food constituent or ingredient that is required for or aids in the support of life. 1


Ingestion, digestion or assimilation of food by plants or animals. 1

Nutritive Value*

Relative capacity of a given forage or other feedstuff to furnish nutrition for animals. In range management, the term is usually prefixed by high, low or moderate. 1


Oblique Imagery**

Images that are taken when the camera or imaging sensor is not pointed at nadir (i.e., straight down).2

Open Herding*

Allowing a herd to spread naturally while grazing. cf. free ranging.1

Open Range*

(1) Range which has not been fenced into management units. (2) All suitable rangeland of an area upon which grazing is permitted. (3) Untimbered rangeland. (4) Range on which the livestock owner has unlimited access without benefit of land ownership or leasing. 1

Opening Date*

(1) The date on which an established grazing season begins. (2) The date on which a legally established hunting or fishing season begins. 1

Operating Unit*

Syn. ranch. 1

Opportunistic Species*

A species adapted for utilizing variable, unpredictable or transient environments; tends to be characteristic of ephemeral plants. 1

Opportunity Cost*

The financial returns given up by not putting a factor of production, particularly capital, to a different use. 1


Any living entity; plant, animal, fungus, etc.1


An offspring whose mother has died. 1


A photograph derived from a conventional perspective photograph by simple or differential rectification so that image displacements caused by camera tilt and relief of terrain are removed.2


The exposure of bedrock or strata projecting through the overlying cover of detritus and soil. 1

Oven-Dry Weight*

The weight of a substance after it has been dried in an oven at a specific temperature to equilibrium. 1

Overall Accuracy**

The percentage of correctly classified pixels.2

Overgrazed Range*

A range which has experienced loss of plant cover and accelerated erosion as a result of heavy grazing or browsing pressure. 1


Continued heavy grazing which exceeds the recovery capacity of the community and creates a deteriorated range. cf. overuse. 1

Overland Flow*

Surface runoff of water following a precipitation event. cf. runoff. 1


Placing a number of animals on a given area that will result in overuse if continued to the end of the planned grazing period. 1


The upper canopy or canopies of plants. Usually refers to trees, tall shrubs and vines. 1


Utilizing an excessive amount of the current year's growth which, if continued, will result in range deterioration. cf. overgrazing. 1



(1) A grazing area that is a subdivision of a grazing management unit, and is enclosed and separated from other areas by a fence or barrier. (2) A relatively small enclosure used as an exercise and saddling area for horses, generally adjacent to stalls or stable. cf. grazing management unit, pasture. 1


The relish with which a particular species or plant part is consumed by an animal. 1

Pan (Soils)*

Horizon or layer in soils that is strongly compacted, indurated, or very high in clay content. cf. caliche, claypan, hardpan. 1


A panchromatic sensor or a panchromatic band that is sensitive to all of the wavelengths in the visible light spectrum. It is commonly presented as a black-and-white image.


(1) A relatively small opening of grassland in a forest. (2) A land area reserved and managed to protect an outstanding landscape and to make it available for public enjoyment. 1

Partial Budgeting*

A limited budgeting procedure used to evaluate a proposed investment in an existing earning enterprise requiring only that additional costs and returns associated with the investment be considered; results often expressed in terms of an internal rate of return. 1

Partido System*

In the southwestern United States, a form of operation in which sheep or cattle owned by the patron are let out on shares to a partidero, who cares for them and returns part of the increase or income to the owner. archaic.1

Passive Remote Sensing**

A sensing system that detects or measures radiation emitted or reflected by the target.Typically, the energy detected with passive remote sensing is reflected sunlight or emitted heat. 2

Pasture Planting*

Establishing adapted herbaceous species on land to be treated and grazed as pasture.1


(1) A grazing area enclosed and separated from other areas by fencing or other barriers; the management unit for grazing land. (2) Forage plants used as food for grazing animals. (3) Any area devoted to the production of forage, native or introduced, and harvested by grazing. (4) A group of subunits grazed within a rotational grazing system. (5) v. To feed on pasture; to use as pasture. 1


Grazing lands, planted primarily to introduced or domesticated native forage species, which receive periodic renovation and/or cultural treatments such as tillage, fertilization, mowing, weed control and irrigation. 1


A condition where the soil has eroded from around individual plants or other objects such as small rocks, leaving them on small pedestals of soil. Sometimes the result of frost heaving. 1

Percent Use*

Grazing use of current growth, usually expressed as a percent of the current growth (by weight) which has been removed. cf. degree of use. 1


The flow of liquid through a porous substance. 1

Perennial Plant*

A plant that has a life span of 3 or more years.1

Period of Occupation*

The length of time that a specific land area is occupied, whether by one animal group or by two or more animal groups in succession. cf. first-last grazing, forward creep grazing, period of stay. 1

Period of Stay*

The length of time that a particular animal group occupies a specific land area. Period of occupation and period of stay differentiate between the total time a specific land area is utilized and the time that a particular group of animals is using said land area. The term is useful in describing grazing methods such as first-last grazing. cf. first-last grazing, forward-creep grazing, period of occupation. 1

Permanent Water*

A watering place which supplies water at all times throughout the year or grazing season. 1


One who holds a permit to graze livestock on state, federal, or certain privately owned lands. Syn. lessee. 1


Any chemical agent such as herbicide, fungicide, insecticide, etc., used for control of specific organisms. 1


The study of periodic biological phenomena which are recurrent such as flowering, seeding, etc., especially as related to climate. 1


The physical appearance of an individual as contrasted with genetic makeup or genotype. 1

Phenoxy Herbicide*

Syn. translocated herbicide. 1

Photo Interpretation*

The art and science of identifying objects and conditions from photographs. 1

Photo Scale*

Photo scale, or representative fraction (RF), is the ratio of the distance measured on the photograph to the distance measured at the ground datum. Photo scale can also be defined as the ratio of the focal length of the camera to the height of the lens above the ground datum at the moment of exposure. 1


Measurements made from aerial photographs including area measurements, distance, direction, height or differences in elevation or slope and the processes of mapping. 1


An identified point from which photographs are taken at periodic intervals. 1


A non-contagious disease resulting from the abnormal reaction of light-colored skin to sunlight after a photodynamic agent has been absorbed through the animal's system. Grazing certain kinds of vegetation or ingesting certain molds under specific conditions causes photosensitization. 1


The origin and evolution of higher taxa. 1


Total amount of plants (including dead attached parts) above and below ground in an area at a given time. cf. biomass. 1


One modular unit of a plant; consisting of the leaf, sheath (or petiole) and internode. 1


Toxic to plants. 1

Picture Point*

A point that can be exactly identified on an aerial photograph. 1

Pioneer Species*

A plant or animal capable of establishing itself in a bare or barren area and initiating an ecological cycle. 1


Making shallow pits or basins of suitable capacity and distribution on range to reduce overland flow from rainfall or snowmelt. 1


“Picture element” is the ground area corresponding to a single element of a digital image data set. A two-dimensional ensemble of pixels forms the geometric grid on which an image is built. The fundamental parameter describing this grid is the inter-pixel spacing in each of the two image directions. (To confuse matters, pixel spacing is often referred to as “pixel” or “pixel size” in the literature. Pixel “size” is to be avoided.)2


A broad stretch of relatively level treeless land. 1

Plant Association*

A kind of climax plant community consisting of stands with essentially the same dominant species in corresponding layers. 1

Plant Community Type*

See community type.1

Plant Community*

An assemblage of plants occurring together at any point in time, thus denoting no particular successional status. A unit of vegetation. 1

Plant Succession*

Vegetation change.1

Plant Symbol*

An abbreviation used to indicate the genus and species of a plant. 1

Plant Vigor Index*

An estimate of plant vigor based on measurement of one or more attributes. 1

Plant Vigor*

Plant health. cf. plant vigor index. 1


The vehicle which carries a sensor. i.e. satellite, aircraft, balloon, etc…2


Abbreviation for pure live seed.1

Poisonous Plant*

A plant containing or producing sub- stances that cause sickness, death or a deviation from the normal state of health of animals. cf. toxic plant species. 1


An anti-foaming agent fed to prevent legume bloat in ruminants.1

Potential Natural Community*

See potential natural vegetation. 1

Potential Natural Vegetation*

A historical term originally defined by A. W. Kuchler as the stable vegetation community which could occupy a site under current climatic conditions without further influence by people. Often used interchangeably with Potential Natural Community. 1

Potential Plant Community*

One of usually several plant communities that may become established on an ecological site under the present environmental conditions, either with or without interference by man. 1


The probability of concluding that a change has occurred when there really has been a change.


Nearly level or rolling grassland, originally treeless, and usually characterized by fertile soil.1


Condensation from the atmosphere, falling as rainfall, snow, hail or sleet. 1


See grazing preference. 1

Preferred Species*

Species that are preferred by animals and are grazed by first choice. 1

Premature Grazing*

Grazing before range readiness; may be allowable if done infrequently and followed by adequate rest. 1

Preparatory Crop*

A residue-producing temporary crop utilized as part of seedbed preparation to provide mulch into which forage plants can be direct seeded. 1


Initial stages of data processing where the image is corrected for various errors and degradation.2

Prescribed Burning*

The use of fire as a management tool under specified conditions for burning a predetermined area. cf. maintenance burning. 1

Primary Production*

The conversion of solar energy to chemical energy through the process of photosynthesis. It is represented by the total quantity of organic material produced within a given period by vegetation. 1

Primary Productivity*

The rate of conversion of solar to chemical energy through the process of photosynthesis. 1

Primary Range*

Areas which animals prefer to use when management is limited. Primary range will be overused before secondary range is fully used. 1

Prior Use*

Grazing use preceding a specific time. 1

Priority Use*

The order of right or privilege to use land based on occupancy, use prior to a certain date, need or other criteria. 1


A state of ecological stability or condition existing in the absence of direct disturbance by modem man. 1

Problem Area*

An area which is difficult to manage because of its shape, size, accessibility or other limiting factors. 1


An organism that can use radiant energy to synthesize organic substances from inorganic materials,e.g. green plants. 1

Producer's Accuracy**

A measure of the accuracy of a particular classification scheme. It shows what percentage of a particular ground class was correctly classified. It is calculated by dividing the number of correct pixels for a class by the actual number of ground truth pixels for that class.2


The rate of production per unit area, usually expressed in terms of weight or energy. 1


Any part of an organism, produced sexually or asexually that is capable of giving rise to a new individual. 1

Proper Grazing*

The act of continuously obtaining proper use. 1

Proper Stocking*

Placing a number of animals on a given area that will result in proper use at the end of the planned grazing period. Continued proper stocking will lead to proper grazing. 1

Proper Use Factor*

An index to the grazing use that may be made of a specific forage species, based on a system of range management that will maintain the economically important forage species, or achieve other management objectives such as maintenance of watersheds, recreation values, etc. 1

Proper Use*

A degree of utilization of current year's growth which, if continued, will achieve management objectives and maintain or improve the long-term productivity of the site. Proper use varies with time and systems of grazing. Syn. proper utilization, proper grazing use, cf. allowable use. 1

Proper Woodland Use*

Grazing, where woodland grazing is a planned use, at an intensity that will maintain adequate cover for soil protection and maintain or improve the quantity of trees and forage. 1

Pure Live Seed*

Purity and germination of seed expressed in percent; may be calculated by formula: P.L.S.= % germination x % purity + 100, e.g. 91 x 96 = 87.36%. Abbr., PLS or P.L.S. cf. seed purity. 1001

Put-and-Take Stocking*

The use of variable animal numbers during a grazing period or grazing season, with a periodic adjustment in animal numbers in an attempt of maintain desired sward management criteria, i.e., a desired quantity of forage, degree of defoliation, or grazing pressure. 1



A temporary resting phase characterized by reduced activity, inactivity or cessation of development. 1



A measure of the energy radiated by the object together with the frequency distribution of that radiation.2


The emission of energy that travels in waves through space or some other medium2

Radiometric Correction**

Calibration of recorded radiance values reflected from (or emitted by) the ground scene. Procedure calibrates and corrects the radiation data provided by sensor detectors.2

Radiometric Resolution

The number of discrete values used by an imaging sensor to record radiance. Radiometric resolution is typically described in terms of the amount of computer memory required to represent each discrete value (i.e., digital number). For example, an image with 8-bit radiometric resolution can have 28=256 values (i.e., values range from 0 to 255). As each pixel takes as much computer memory to store as its radiometric resolution, lower radiometric resolutions save computer memory. However, higher radiometric resolutions have better capability to discriminate smaller differences in radiance. This can be very important when dealing with images with extensive shadows. Low radiometric resolution imagery may record shadows as all one value; whereas high radiometric resolution imagery may recognize enough variation within the shadows to allow for classification of land cover in shadowed areas.

Rain Shadow*

The region of diminished rainfall on the lee side of a mountain range, where the rainfall is noticeably less than on the windward side. 1


Syn. guzzler; catchment basin; cf. trick tank. 1


An establishment or firm with specific boundaries together with its lands and improvements, used for the grazing and production of domestic livestock and/or wildlife. 1


One who owns, leases or manages a ranch. 1

Range Administration*

The conduct of the affairs of a range. 1

Range Appraisal*

The classification and valuation of rangeland from an economic or production standpoint. 1

Range Condition Class*

One of a series of arbitrary categories used to classify range condition as that term has been variously defined. See range condition.1

Range Condition*

Historically, has usually been defined in one of two ways: (a) a generic term relating to present status of a unit of range in terms of specific values or potentials. Specific values or potentials must be stated. (b ) the present state of vegetation of a range site in relation to the climax (natural potential) plant community for that site. It is an expression of the relative degree to which the kinds, proportions, and amounts of plants in a plant community resemble that of the climax plant community for the site. This term is being phased out. Preferred terms are successional status and range similarity index. 1

Range Degradation*

The process that 1eads to an irreversible reduction in capability of an ecological site to produce vegetation. 1

Range Discipline*

A branch of knowledge pertaining to the use and management of range. Syn. range management.1

Range Examiner*

A person who collects and compiles information pertaining to range management and who prepares grazing management plans. Syn. range manager, range conservationist. archaic. 1

Range Forage*

Forage produced on rangeland. cf. forage, cured forage. 1

Range Improvement*

Any activity or program on or relating to rangelands which is designed to improve production of forage, change vegetation composition, control patterns of use, provide water, stabilize soil and water conditions, or provide habitat for livestock and wildlife. 1

Range Lambing*

Permitting females to drop their offspring on the range under approximately natural conditions of shelter and forage. cf. shed lambing. 1

Range Management*

A distinct discipline founded on ecological principles and dealing with the use of rangelands and range resources for a variety of purposes. These purposes include use as watersheds, wildlife habitat, grazing by livestock, recreation, and aesthetics, as well as other associated uses. 1

Range Plan*

Syn. management plan. 1

Range Readiness*

The defined stage of plant growth at which grazing may begin under a specific management plan without permanent damage to vegetation or soil. Usually applied to seasonal range. 1

Range Research*

A systematic, critical inquiry seeking facts and knowledge pertinent of range. 1

Range Reseeding*

Syn. range seeding. 1

Range Resources*

Syn. related resources. 1

Range Science*

The organized body of knowledge upon which the practice of range management is based. 1

Range Seeding*

The process of establishing vegetation by the artificial dissemination of seed. 1

Range Site*

Syn. of ecological site on rangeland. 1

Range States*

In the U.S., generally considered as the seventeen western states excluding Alaska and Hawaii. In these states, the major portion of the land is used for the production of livestock from range. 1

Range Type*

An historical term that refers to, and only to, the 18 standard range vegetation types recognized by the 1937 Task Force (Interagency Range Survey Committee, 1937). 1

Range User*

The individual or organization using rangeland for a specific purpose. Most commonly associated with one having a permit to graze livestock on public land, but a hunter may also be considered a range user. 1


(n.) Land supporting indigenous vegetation that either is grazed or that has the potential to be grazed, and is managed as a natural ecosystem. Range includes grassland, grazable forestland, shrubland and pastureland. Range is not a use. (adj.) Modifies resources, products, activities, practices, and phenomena pertaining to rangeland. cf. rangeland, forested range, grazable woodland, shrubland, pastureland.1

Rangeland Health*

The degree to which the integrity of the soil, the vegetation, the water, and air as well as the ecological processes of the rangeland ecosystem is balanced and sustained. Integrity is defined as: Maintenance of the structure and functional attributes characteristic of a particular locale, including normal variability. 1

Rangeland Hydrology*

The study of hydrological principles as applied to range ecosystems. 1

Rangeland Inventory*

(v.) The systematic acquisition and analysis of resource information needed for planning and for management of rangeland. (n.) The information acquired through range inventory. 1

Rangeland Remote Sensing*

The detection, identification and assessment of condition of objects on rangelands with a camera, or other imaging device, situated at an appreciable distance from the imaged subject. 1

Rangeland Renovation*

Improving rangeland by mechanical, chemical or other means. 1

Rangeland Similarity Index*

The present state of vegetation and soil protection of an ecological site in relation to the historic climax plant community for the site. Syn. range condition. (b). 1


Land on which the indigenous vegetation (climax or natural potential) is predominantly grasses, grass-like plants, forbs, or shrubs and is managed as a natural ecosystem. If plants are introduced, they are managed similarly. Rangeland includes natural grasslands, savannas, shrublands, many deserts, tundras, alpine communities, marshes and meadows. 1

Ration Grazing*

Confining animals to an area of grazing land to provide the daily allowance of forage per animal. cf. strip grazing. 1

Reaction Intensity

The rate of heat release, per unit area of the flaming fire front, expressed as heat energy/area/time, such as Btu/square foot/minute, or Kcal/square meter/second. Also referred to as combustion rate. 6


Restoration of a site or resource to a desired condition to achieve management objectives or stated goals. cf. revegetation. 1


A general examination or survey of a region with reference to its main features, usually as a preliminary act of a more detailed survey. 1

Recreation Area*

A developed or undeveloped land area reserved and managed for recreational purposes. 1

Red Edge**

Spectral region at the limit of the red and near-infrared wavelengths characterized by a sharp rise in the plant reflectance.2

Reference State

The state where the functional capacities represented by soil/site stability, hydrologic function, and biotic integrity are performing at an optimum level under the natural disturbance regime. This state usually includes, but is not limited to, what is often referred to as the potential natural plant community (PNC).3


Ratio of the intensity of reflected radiation to that of the incident radiation on a surface. The suffix (-ance) implies a property of that particular specimen surface.2


A statistical method that establishes the relationship between a dependent variable and one or more independent, predictor variables. Regression is a “best fit” approach to finding the relationship between the dependent and independent variables, and because of that, some error in prediction is expected. Regression analysis can be used to determine how closely related a set of variables are, and, if there is a reasonably strong relationship, can be used to make predictions of the dependent variable based on measurements of the independent variables. Linear_Regression

Rejuvenation (Browse)*

Treatments such as mechanical, pyric or even chemical, applied to woody plants to encourage new growth as sprouts or seedlings available for browsing. 1

Those resources which bear relation- ship to one another because of common location and inter- dependency, such as range, game, recreation, watershed, soil, timber, etc. 1


A remnant or fragment of the climax plant community that remains from a former period when it was more widely distributed. Syn. pristine. 1

Remote Sensing*

The measurement or acquisition of information of some property of an object or phenomenon by a recording device that is not a physical or intimate contact with the object or phenomenon under study. Often involves aerial photography or satellite imagery. 1

Repeated Seasonal Grazing*

A grazing strategy in which different kinds of pastures are arranged in a series and each is grazed at the same time each year, often for less than the full feasible grazing season to provide a special use. Syn. seasonal grazing. 1


Syn. range seeding. 1

Resident Species*

Species common to an area without distinction as to being native or introduced. 1


Forage remaining on the land as a consequence of harvest. 1


Typically synonymous with ground resolution or pixel dimension. Alternately, it is the smallest object or narrowest line a sensor can detect. 2

Resource Value Rating (RVR)*

The value of vegetation present on an ecological site for a particular use or benefit. RVR's may be established for each plant community capable of being produced on an ecological site, including exotic or cultivated species. 1

Rest Period*

The length of time that a specific land area is allowed to rest. Syn. spelling period, cf. rest. 1


To leave an area of grazing land ungrazed or unharvested for a specific time, such as a year, a growing season or a specified period required within a particular management practice. Syn. spell, cf. rest period, ungrazed, deferment. 1

Restricted Area*

An area on which grazing tenure is limited. 1


A grazing management scheme in which rest periods for individual pastures, paddocks or grazing units, generally for the full growing season, are incorporated into a grazing rotation. cf. grazing system. See rotational stocking. 1


An historical term used by some ecologists to mean succession in reverse. According to Clements (1916), however, retrogression is synonymous with destruction and denudation of a community. 1


Establishing or re-establishing desirable plants on areas where desirable plants are absent or of inadequate density, by management alone (natural revegetation) or by seeding or transplanting (artificial revegetation). cf. range seeding. 1


A horizontal underground stem, usually sending out roots and aboveground shoots from the nodes. 1


Describes the correlation between the sampling unit values in the first time period and the second time period. Increasing rho reduces the number of samples required. For comparisons between two independent plots, rho=0. Once data has been collected at the same location at two different time periods, rho can be calculated. For pilot sampling data, rho is given a predicted value (0.5-0.75).

Riding Down*

Pushing over small trees and shrubs by livestock or wildlife in order to reach the browse. archaic.1

Riparian Community Type*

A recurring, classified, defined and recognizable assemblage of riparian plant species. 1

Riparian Ecosystems*

(1) Those assemblages of plants, animals, and aquatic communities whose presences can be either directly or indirectly attributed to factors that are water-influenced or related. (2) Interacting system between aquatic and terrestrial situations identified by soil characteristics, and distinctive vegetation that requires or tolerates free or unbound water. 1

Riparian Species*

Plant species occurring within the riparian zone. Obligate species require the environmental conditions within the riparian zone; facultative species tolerate the environmental conditions, and may occur away from the riparian zone. 1

Riparian Vegetation*

Plant communities dependent upon the presence of free water near the ground surface (high water table). 1

Riparian Zone*

The banks and adjacent areas of water bodies, water courses, seeps and springs whose waters pro- vide soil moisture sufficiently in excess of that otherwise available locally so as to provide a more moist habitat than that of contiguous flood plains and uplands. 1


Referring to or relating to areas adjacent of water or influenced by free water associated with streams or rivers on geologic surfaces occupying the lowest position on a watershed. 1


The mechanical penetration and shearing of range soils to depths of 8 to 18 inches for the purpose of breaking hardpan layers to facilitate penetration of plant roots, water, organic matter, and nutrients. A range improvement practice used where native grasses of a rhizomatous nature can spread into the ripped soil. cf. chiseling. 1

Rodent Control*

Measures taken to reduce or control the rodent population of a given area. This may apply to a specific species or rodents in general. cf. rodent. 1


Any animal of the order Rodentia, and commonly includes the order Lagomorpha, many of which influence the range through such habits as grazing, burrowing, etc. Important range rodents include pocket gophers, prairie dogs, ground squirrels, certain terrestrial mice, kangaroo rats, jackrabbits and marmots. 1

Rotation Grazing*

A grazing scheme where animals are moved from one grazing unit (paddock) in the same group of grazing units to another without regard to specific graze: rest periods or levels of plant defoliation. cf. grazing system. 1

Rotational Deferred*

Systematic rotation of deferment among land areas within a grazing management unit. 1

Rotational Stocking*

A grazing method that utilizes recurring periods of grazing and rest among two or more paddocks in a grazing management unit throughout the period when grazing is allowed. The lengths of the grazing and of the rest periods should be defined. Words such as controlled or intensive are sometimes used in an attempt to describe the degree of grazing management applied to this grazing method. These words are not synonyms for rotational stocking. cf. continuous stocking.1


(1) The accumulation of mature living and dead vegetation, especially grasses and forbs, on forest range, marshland or prairie. (2) May refer to land surface with uneven terrain. 1


Plant materials containing a low proportion of nutrients per unit of weight and usually bulky and coarse, high in fiber and low in total digestible nutrients. Roughage may be classed as either dry or green. 1


The purposeful gathering of animals into a herd by man. 1


A plant inhabiting disturbed sites. 1


The large, first compartment of the stomach of a ruminant from which ingested food is regurgitated for re-chewing and in which digestion is aided by symbiotic action of microbes. 1


Even-toed, hoofed mammals that chew the cud and have a 4-chamber stomach., i.e. Ruminantia. 1


The total stream discharge of water, including both surface and subsurface flow, usually expressed in acre-feet of water yield. 1

Runoff, Groundwater*

Precipitation which percolates through the soil mantle to the groundwater table and is eventually discharged into a stream. 1

Runoff, Surface*

That part of runoff that travels over the soil surface to a stream channel. Syn. overland flow. 1


(1) An energetic animal well able to shift for itself. (2) A thief of livestock. 1


Sacrifice Area*

A portion of the range, irrespective of site, that is unavoidably overgrazed to obtain efficient overall use of the management area. 1

Sacrifice Site*

A range site that is unavoidably overgrazed to obtain efficient overall use of the management area. 1

Salt Ground*

An area where salt is placed for use by livestock or game; often relocated periodically to achieve improved animal distribution. 1

Salt Lick*

Spots containing unusually large quantities of salts in the soil where animals consume the soil to obtain salt.1


(1) Providing salt as a mineral supplement for animals. (2) Placing salt on the range in such a manner as to improve distribution of livestock grazing.1


A part of a population taken to estimate a parameter of the whole population. 1

Sand Tank*

A water development constructed by placing a dam in a rock-bound channel and bonded to bedrock, and using the sand/gravel trap above the dam for water storage. 1


A vehicle put into orbit around the earth or other body in space and used as a platform for data collection and transmission.2


Grassland with scattered trees or shrubs; often a transitional type between true grassland and forestland, and accompanied by a climate with alternating wet and dry seasons. 1


The process in which a wave or beam of particles is diffused or deflected by collisions with particles of the medium which it traverses.2


Vegetation dominated by short, stunted woody plants growing thickly together or intermingled with cacti. 1

Seasonal Distribution*

(1) The progressive grazing in a sequence of moves from one part of a range to another as vegetation develops. (2) The normal occurrence of precipitation at different periods of the year. 1

Seasonal Grazing*

Grazing restricted to one or more specific seasons of the year. 1

Seasonal Use*

(1) Synonymous with seasonal grazing. (2) Seasonal preference of certain plant species by animals. 1

Seasonal Zone*

An area of the range which livestock and wildlife prefer at certain seasons. 1

Secondary Range*

Range which is lightly used or unused by livestock under minimal management and will ordinarily not be fully used until the primary range has been overused. 1

Seed Certification*

A system whereby seed of plant cultivars is produced, harvested and marketed under authorized regulation to insure seed of high quality and genetic purity. 1

Seed Dribbler*

A metering device that drops seed onto the track of a crawler tractor for the purpose of being carried forward and pressed into the ground as the tractor passes. 1

Seed Inoculation*

Treatment of legume seed with rhizobium bacteria before planting to enhance subsequent nitrogen fixation. 1

Seed Purity*

The percentage of the desired species in relation to the total quantity, including other species, weed seed, and foreign matter. cf. pure live seed. 1

Seed Scarification*

Mechanical or acid treatment of seed-coats to improve water absorption and enhance germination. 1


A fertilized ripened ovule of a flowering plant. 1

Seed, Dormant*

Live seed in a non-germinative condition because of (1) internal inhibitions in seed, i.e., hard seed, or (2) unfavorable environmental conditions. cf. seed, hard. 1

Seed, Hard*

Live seed in a physiological condition that prevents or delays germination, even when a favorable environment exists. cf. seed, dormant. 1

Seedbed Preparation*

Soil treatment prior to seeding to: (1) reduce or eliminate existing vegetation, (2) reduce the effective supply of weed seed, (3) modify physical soil characteristics and (4) enhance temperature and water characteristics of the micro-environment. 1


Wet areas, normally not flowing, arising from an underground water source. 1


The process by which an image is divided into spatial regions of like attribute.2

Selective Grazing*

The grazing of certain plant species, individual plants, or plant parts on the range to the exclusion of others. 1

Selectivity Ratio*

The fraction or decimal indicating the proportion of the diet contributed by a plant species, species group, or plant part; an expression of relative preference. 1


A term applied to regions or climates where moisture is normally greater than under arid conditions, but still definitely limits the production of vegetation. The upper limit of average annual precipitation in the cold, semiarid regions is as low as 15 inches (380 mm), whereas in warm tropical regions it is as high as 45-50 inches (1,100-1,300mm). 1


A path or lane cut or dozed through brushy areas to provide access by livestock, pedestrians, or vehicles. A term commonly used in the Southwest. cf. browse way. 1

Sequence Grazing*

The grazing of two or more land units in succession that differ in forage species composition. Sequence grazing takes advantage of differences among forage species combinations, grown in separate areas for management purposes, to extend forage quality and/or quantity, or achieve some other management objective. 1

Seral Community*

The relatively transitory communities that develop under plant succession. Syn. seral stage. 1

Seral Stages*

The relatively transitory communities that develop under plant succession. Syn. seral community. 1


Refers to species or communities that are eventually replaced by other species or communities within a sere. 1


The whole series of communities that develop in a given situation during plant succession. 1

Set Stocking*

The practice of allowing a fixed number of animals on a fixed area of land during the time when grazing is allowed. cf. variable stocking. 1

Sex Ratio*

The ratio existing between the number of male and female animals within a given herd, band or population. 1


A decrease in the brightness caused by a feature (cloud, mountain, etc.) blocking the path of the in-coming radiation. This reduction in the strength of the signal (which corresponds to the decrease in brightness) means that some of the image will be obscured and useful information may be more difficult or impossible to extract.2

Shearing Plant*

A general term used to describe the buildings, machinery, pens and other appurtenances of an establishment where animals are shorn.1

Shed Lambing*

Housing and feeding females during the time offspring are dropped. cf. range lambing.1


Range vegetation having dwarf oaks as dominants. 1

Short-Duration Grazing*

Grazing management whereby relatively short periods (days) of grazing and associated non-grazing are applied to range or pasture units. Periods of grazing and non-grazing are based upon plant growth characteristics. Short duration grazing has nothing to do with intensity of grazing use. cf. grazing system. 1


A plant that has persistent, woody stems and a relatively low growth habit, and that generally produces several basal shoots instead of a single bole. It differs from a tree by its low stature (generally less than 5 meters, or 16 feet) and non-arborescent form. 1


Land on which the vegetation is dominated by shrubs. 1


Preferred term is Forest grazing. 1

Site Conservation Rating (SCR)*

An assessment of the protection afforded a site by the current vegetation against loss of potential. SCR greater than Site Conservation Threshold (SCT) is considered a “satisfactory” SCR and below SCT is considered an “unsatisfactory” SCR. 1

Site Conservation Threshold (SCT)*

The kind, amount and/or pattern of vegetation needed as a minimum on a given site to prevent accelerated erosion. 1


The place or seat of any specified thing. cf. administrative site, range site. 1


The development of a line of uniform height of vegetation which gives an illusion of a horizon usually associated with excessive use of browse. May refer to either top line or under line. Syn. highlining 1


A slant or incline of the land surface, measured in degrees from the horizontal, or in the percent (defined as the number of feet or meters change in elevation per l00 of the same units of horizontal distance); may be further characterized by direction (exposure). 1

Snow Fence*

A fence used to retard or alter the movement of snow by wind. 1

Sod Grasses*

Stoloniferous or rhizomatous grasses which form a sod or turf. cf. bunchgrass. 1

Sod Seeding*

Direct drilling of seed on sites on which no seedbed preparation had been made.1


Vegetation which grows so as to form a mat of soil and vegetation. Syn. turf 1


(1) The unconsolidated mineral and organic material on the immediate surface of the earth that serves as a natural medium for the growth of land plants. (2) The unconsolidated mineral matter on the surface of the earth that has been subjected to and influenced by genetic and environmental factors of parent material, climate (including moisture and temperature effects), macro- and micro- organisms, and topography, all acting over a period of time and producing a product-soil-that differs from the material from which it was derived in many physical, chemical, biological, and morphological properties and characteristics. 1

Soil-adjusted Vegetation Index (SAVI)**

A vegetation index that accounts for, and minimizes, the effect of soil background conditions.2

Spatial Analysis**

Study of spatial arrangement of points, lines, objects, etc.., in images.2

Spatial Autocorrelation

A measure of how similar or dissimilar features tend to be to each other with respect to the distance between them. The degree to which the values of a set of measurements is clustered or dispersed in space. A common assumption of traditional statistics is that observations are independent - meaning that spatial autocorrelation is zero. Alternatively, spatial statistical techniques require spatial autocorrelation.

Spatial Data**

Data that refers to a location (which may be a specific location on the Earth's surface, or relative to an arbitrary point).2

Spatial Resolution**

A measure of the smallest separation (using either linear or angular units) between two objects. See also Ground Resolution2

Spatial Variance

See Spatial Autocorrelation

Species Composition*

The proportions of various plant species in relation to the total on a given area. It may be expressed in terms of cover, density, weight, etc. 1


A taxon or rank species; in the hierarchy or bio- logical classification, the category below genus. 1

Spectral Resolution**

The ability of a sensing system to differentiate different portions of the electromagnetic spectrum. High spectral resolution sensors have many bands with narrowly defined wavelengths. Low spectral resolution sensors have a single or few bands that each cover broad regions of the electromagnetic spectrum. 2


A device used to measure radiation from the electromagnetic spectrum or to determine the wavelengths of various radiations.2

Spot Grazing*

Repeated grazing of small areas while adjacent areas are lightly grazed or unused. 1

Spray Drift*

The movement of airborne spray particles from the intended area of application, i.e., horizontal displacement. 1

Spreader Dam*

Syn. water spreader.1


Flowing water originating from an underground source. 1

Spring-Fall Range*

Range that is grazed primarily during the spring and fall. 1

Standing Crop*

The total amount of plant material per unit of space at a given time. Often is divided into above ground and below ground portions and further may be modified by the descriptors “dead” or “live” to more accurately define the specific type of biomass. 1


The culm or branch of a plant. 1


Semi-arid grassland characterized by grasses occurring in scattered bunches with other herbaceous vegetation and occasional woody species. 1

Stock Driveway*

Syn. driveway. 1

Stock Trail*

A trail constructed across a natural barrier to permit movement of livestock to otherwise inaccessible areas. 1


Livestock. 1

Stocking Density*

The relationship between number of animals and the specific unit of land being grazed at any one point in time. May be expressed in animal units per unit of land area (animal units at a specific time/area of land.). cf. stocking rate. 1

Stocking Plan*

The number and kind of livestock assigned to one or more given management areas or units for a specified period. 1

Stocking Rate*

The relationship between the number of animals and the grazing management unit utilized over a specified time period. May be expressed as animal units per unit of land area (animal units over a described time period/area of land). cf. stocking density.1

Stockpiling Forage*

(v.) To allow forage to accumulate for grazing at a later period. Forage is often stockpiled for autumn and winter grazing, after or during dormancy or semi-dormancy, but stockpiling may occur at any time during the year as a part of a management plan. Stockpiling can be described in terms of deferment and forage accumulation. 1


Allowing standing forage to accumulate for grazing at a later period, often for fall and winter grazing after dormancy. cf. cured forage. 1


A water impoundment made by constructing a dam or by excavating a dugout or both, to provide water for livestock and wildlife. cf. catchment, guzzler; trick tank. 1

Stockwater Development*

Development of a new or improved source of stockwater supply, such as well, spring, pond, together with storage and delivery system. 1


A horizontal stem which grows along the surface of the soil and roots at the nodes. 1

Strip Grazing*

Confining animals to an area of grazing land to be grazed in a relatively short period of time, where the paddock size is varied to allow access to a specific land area. Strip grazing may or may not be a form of rotational stocking, depending on whether or not specific paddocks are utilized for recurring periods of grazing and rest. cf. rotational stocking, ration grazing. 1


The basal portion of herbaceous plants remaining after the top portion has been harvested either artificially or by grazing animals. 1

Submarginal Land*

Land that is either physically or economically incapable of indefinitely sustaining a certain use. 1

Substitution Ratio*

Number of animals or animal-units of one kind or class that can be substituted for another kind or class to meet a specified management objective. Syn. animal-substitution ratio.1


The subdivisions of a single grazing system. cf. paddock, pasture. 1


The progressive replacement of plant communities on a site which leads to the potential natural plant community; i.e., attaining stability. Primary succession entails simultaneous succession of soil from patent material and vegetation. Secondary succession occurs following disturbances on sites that previously supported vegetation, and entails plant succession on a more mature soil. cf. plant succession. 1

Successional Status*

The present state of vegetation and soil protection of an ecological site in relation to the potential natural community for the site. Successional status is the expression of the relative degree to which kinds, proportions and amounts of plants in a community resemble that of the potential natural community. If classes or ratings are used, they should be described in successional rather than utilization terms. For example, some agencies are utilizing four classes of successional status ratings (early seral, mid-seral, late seral, potential natural community) of vegetation corresponding to 0-25%, 26-50%, 51-75% and 76-100% of the potential natural community standard. Soil status is a measure of present vegetation and litter cover relative to the amount of cover needed on the site to prevent accelerated erosion. This term is not used by all agencies. cf. range condition.1

Summer Range*

Range, particularly in the mountainous western states, that is grazed primarily during the summer growing season. 1

Sun-synchronous Orbit**

The path of a satellite in which the orbital plane is near-polar and the altitude is such that the satellite passes over the same latitude at approximately the same local (sun) time each day. Sun-synchronous orbits are well suited for higher resolution imaging and are generally used by Earth resource satellites. Compared to a geostationary orbit, the lower altitudes of sun-synchronous orbits make it technically easier to produce high spatial resolution imagery capable of resolving smaller features on the ground. Repeatable illumination facilitates image interpretation and processing such as matching overlapping images to produce a mosaic or comparing images of the same area acquired in the same season but in different years. However, a sun-synchronous orbit does not remove all variation in illumination. The solar elevation angle and illumination intensity varies with latitude and with season. Variations in atmospheric conditions also cause variation in illumination between scenes.2

Image source: Canada Center for Remote Sensing

Supervised Classification**

A procedure for identifying spectrally similar areas on an image by identifying ‘training’ sites of known targets and then extrapolating those spectral signatures to other areas of unknown targets. Supervised classification relies on the a priori knowledge of the location and identity of land cover types that are in the image. This can be achieved through field work, study of aerial photographs or other independent sources of information. 2


Nutritional additive (salt, protein, phosphorus, etc.) intended to remedy deficiencies of the range diet. 1

Supplemental Feeding*

Supplying concentrates or harvested feed to correct deficiencies of the range diet. Often erroneously used to mean emergency feeding. cf. maintenance feeding. 1


(surface active agent). Materials used in herbicide formulations to bring about emulsifiability, spreading, wetting, sticking, dispersibility, solubilization or other surface-modifying properties. 1

Suspension Fence*

Non-woven wire fence comprised of high tension wire supported by rigid stays and widely spaced posts to which wire is not firmly attached. 1

Sustained Yield*

Production of specified resources or commodities at a given rate for a designated unit of time. 1


An area of low and sometimes wet land. 1


A population of herbaceous plants, characterized by a relatively short habit of growth and relatively continuous ground cover, including both above and below ground parts. 1


The width of a single scan or track covered by a sensing system. Also called the range.2


A subdivision of ecology that deals with the study of groups of organisms associated as a unit, i.e., communities. cf. autecology. 1



(1) A label attached, usually to the animal, for identification. (2) A discolored and dirty part of a fleece. 1

Tagging Chute*

A narrow enclosure (of board, pole or steel construction) to hold animals during tagging. 1


(1) Clipping manured and dirty locks from sheep. (2) The process of attaching identifying tags to animals. cf. brand and marking. 1


A reservoir of any construction for water storage. 1

Taproot System*

A plant root system dominated by a single large root, normally growing straight downward, from which most of the smaller roots spread out laterally. cf. fibrous root system. 1

Temporal Resolution**

The frequency in time over which observations are made or images collected2

Temporary License or Permit*

A document authorizing grazing of a certain number of livestock on public lands during an emergency or for a certain period, terminable at the end of such period and with no guarantee of renewal in whole or in part. cf. grazing license or permit. 1

Term License or Permit*

A document which authorizes grazing on public lands for a stated number of years as contrasted with an annual or temporary license or permit. cf. grazing license or permit.1


Mechanical movement of soil along the horizontal contour of a slope to produce an earthen dike to retain water and diminish the potential of soil erosion. 1


The asexual development of a new plant from a meristematic region of the parent plant. 1


Land on which the natural potential vegetation is forest. It may be managed primarily for the production and harvest of timber. 1

Total Annual Yield*

The total annual production of all plant species of a plant community. 1

Toxic Plant Species*

A species of plant which may accumulate or produce a substance toxic to animals. cf. poisonous plant. 1


The chemical ingredient(s) which may injure or cause death in either plant or animal life exposed to it. 1

Trace Element*

An element essential for normal growth and development of an organism but required only in minute quantities. 1

Trail Herding*

Directing and controlling the movement of a group of livestock on restricted overland routes. 1


A well-defined path created by repeated passage of animals. 1


(1) Controlled directional movement of livestock. cf. drive. (2) Natural trailing is the habit of livestock or wildlife repeatedly treading in the same line or path. 1

Training Site**

An identified feature or area on an image established as a comparison standard for the automatic classification of features on this image. A training area is a small sample of homogeneous areas selected by the image analyst prior to classification. Each area is determined from maps, ground data, or other information (e.g. land use database). Training sites should be free of anomalies and be large enough to provide good statistical representation. Also, there should be a sufficient number of sites selected for each class to account for small local variations within the class (e.g. age, health, cultivation, moisture content, etc.). Training areas should avoid edge pixels containing the combined backscatter of multiple targets (mixed pixels), and inconsistencies within the area such as roadways, powerlines, intermittent cover, etc. Once defined, training areas are used to generate signature statistics for each defined class.2


Treading underfoot; the damage to plants or soil brought about by movements or congestion of animals. 1

Translocated Herbicide*

A herbicide which is moved within the plant from the point of entry. Syn. phenoxy herbicide.1


A relatively small enclosure used as a temporary holding or catching area in the handling and management of livestock. 1


A woody perennial, usually single stemmed plant that has a definite crown shape and reaches a mature height of at least 16 feet (5 meters). There is no clear-cut distinction between trees and shrubs. Some plants, such as oaks (Quercus spp.) may grow as either trees or shrubs. 1

Trend (Range Trend) Classes and Successional Status Ratings*

Trend in range condition or successional status should be described as up, down or not apparent. Up rep- resents a change toward climax or potential natural community; down represents a change away from climax or potential natural community; and not apparent indicates there is no recognizable change. This category is often recorded as static or stable. There is no necessary correlation between trends in resource value ratings, vegetation management status, and trend in range condition or successional status. 1


The direction of change in an attribute as observed over time. 1


Syn. grazing trespass. 1

Trick Tank*

A modification of a guzzler in which the collection basin is elevated and the storage tank is located directly below. 1

Trophic Levels*

The sequence of steps in a food chain or food pyramid, from producer to primary, secondary or tertiary consumer. 1


Land areas in arctic and alpine regions devoid of large trees, varying from bare ground to various types of vegetation consisting of grasses, sedges, forbs, dwarf shrubs and trees, mosses, and lichens. 1


Syn. sod. 1


Act of turning livestock out on the range at the beginning of the grazing season. 1

Type Line*

The boundary line which separates two distinctive vegetation types on a map or photograph. 1

Type Mapping*

The process of delineating vegetation types on an aerial photograph or on a base map. 1


Syn. vegetational type. 1


Ultralight Aircraft**

A portable, low-flying and low-speed aircraft constructed with ultralight materials.2

Unauthorized Use*

The grazing of livestock on a range area without proper authority. cf. grazing trespass. 1


The act of continued underuse. 1


Placing a number of animals on a given area that will result in underuse at the end of the planned grazing period. 1


Plants growing beneath the canopy of other plants. Usually refers to grasses, forbs and low shrubs under a tree or shrub canopy. cf. overstory.1


A degree of use less than proper use.1

Undesirable Species*

(1) Species that conflict with or do not contribute to the management objectives. (2) Species that are not readily eaten by animals. 1


(1) The status of grazing land that is not grazed by animals. (2) The status of plants or plant parts that are not grazed by animals. cf. rest. 1


A hoofed animal, including ruminants but also horses, tapirs, elephants, rhinoceroses, and swine. 1

Unsupervised Classification**

Categorization of digital image data by computer processing based solely on the image statistics without availability of training samples or a-priori knowledge of the area. The classification creates natural groupings in the image values, called spectral clusters or classes. In this fashion, values with similar grey levels are assumed to belong to the same cover type. The analyst must then determine the identity of these spectral clusters. Principle clustering algorithms include: K-means clustering, ISODATA clustering, and Narenda-Goldberg clustering.2

Upper Limit*

The maximum size of term permit which may be held by an individual, partnership or corporation. 1

Usable Forage*

That portion of the forage that can be grazed without damage to the basic resources; may vary with season of use, species and associated plant species. 1


(1) The proportion of current year's forage production that is consumed or destroyed by grazing animals. May refer either to a single species or to the vegetation as a whole. Syn. degree of use. (2) Utilization of range for a purpose such as grazing, bedding, shelter, trailing, watering, watershed, recreation, forestry, etc. 1


Syn. use 1


Vapor Drift*

The movement of pesticidal vapors from the area of application. 1

Variable Stocking*

The practice of allowing a variable number of animals on a fixed area of land during the time when grazing is allowed. cf. set stocking. 1


A statistic that describes the spread or distribution of a population or sample around its mean value. A high variance means that there is a large spread around the mean. A low variance means that the population is clustered tightly around the mean. The standard deviation is a form of expressing variance in units that are the same as the mean. Variance is equal to the standard deviation squared. Variance

Vegetation Management Status*

The relative degree to which the kinds, proportions, and amounts of vegetation in the present plant community resemble the desired plant community chosen for an ecological site. 1

Vegetation Type*

A kind of existing plant community with distinguishable characteristics described in terms of the present vegetation that dominates the aspect or physiognomy of the area.1


(n.) Plant life in general. 1

Vegetative Reproduction*

Production of new plants by any asexual method. 1


Non-reproductive plant parts, i.e. leaf and stem, in contrast to reproductive plant parts, i.e. flower and seed, in developmental stages of plant growth. The non-reproductive stage in plant development. Of or relating to vegetation. cf. vegetation. 1

Veld (Veldt)*

The open temperate grassland areas of southern Africa, typically containing scattered shrubs or trees. 1

Viewing angle**

The angle between the looking axis of the sensor and the horizontal or ground elevation surface. At nadir (i.e., looking straight down), the viewing angle is 90 degrees2


Relates to the relative robustness of a plant in comparison to other individuals of the same species. It is reflected primarily by the size of a plant and its parts in relation to its age and the environment in which it is growing. Syn. plant vigor. cf. hybrid vigor.1


Syn. pristine. 1

Visual Observation**

The act of persons (normally in an aircraft) visually sensing and possibly recording various details of the environment.2



An earthen embankment constructed to improve the accessibility of marsh range. 1

Warm-Season Plant*

(1) A plant which makes most or all its growth during the spring, summer or fall and is usually dormant in winter. (2) A plant that usually exhibits the C-4 photosynthetic pathway. 1

Water Gap*

(1) A specially constructed fence across a drainage. The fence is easily moved by the forces of a flood, thus preventing damage to the permanent fence. (2) An opening or fenced area providing access to a developed or natural water supply permitting one watering facility to serve two or more pastures. 1

Water Potential*

The thermodynamic state of the water in a cell, organism, or soil, equal to the difference in free energy per unit volume between matrically bound, pressurized or osmotically constrained water and that of pure water. 1

Water Spreader*

A terrace, dike or other structure intended to distribute surface-water runoff and increase the area of infiltration. 1


(1) A total area of land above a given point on a waterway that contributes runoff water to the flow at that point. (2) A major subdivision of a drainage basin. Waterway. A way or channel for water. 1


The mean distance between maxima (or minimal) of a roughly periodic pattern. Specifically, the least distance between particles moving in the same phase of oscillation in a wave disturbance. Optical and IR wavelengths are measured in nanometres (10-9m), micrometers (10-6m) and Angstroms (10-10m).2


Filter for enhancing, compressing, or generalizing images. Wavelets can be used to filter unnecessary information from imagery and the results used to map features at different scales.2


(1) Any plant growing where unwanted. (2) A plant having a negative value within a given management system. 1

Well, Horizontal*

A water source developed by drilling horizontally into a hillside to intercept a perched water table or underground water source; cf. spring. 1

Wet Meadow*

A meadow where the surface remains wet or moist throughout the growing season, usually characterized by sedges and rushes. cf. meadow, dry meadow. 1

Wetland Communities*

Plant communities that occur on sites with soils typically saturated with or covered with water most of the growing season.1


Areas characterized by soils that are usually saturated or ponded, i.e., hydric soils, that support mostly water-loving plants (hydrophytic plants).1

Wildlife Refuge*

A land area reserved and managed for the benefit of one or more species of wildlife.1


Undomesticated vertebrate animals considered collectively, with the exception of fish. cf. game. 1

Winter Range*

Range that is grazed during the winter months. 1

Wolf Plant*

(1) An individual plant that is generally considered palatable, but is not grazed by livestock. (2) An isolated plant growing to extraordinary size, usually from lack of competition or utilization. Or, in other words, what a plant should look like! 1

Woodland Pasture*

Farm woodlands also used for grazing. 1

Woodland Range*

Woodlands having understory vegetation suitable for grazing. Syn. forested range, grazable woodland. 1


A land area occupied by trees; a forest, woods.1


A term used in reference to trees, shrubs or browse that characteristically contain persistent ligneous material.1


WRS stands for the Worldwide Reference System and is a system for determining what Landsat scenes cover what area. It is based on two things: 1) the orbit pathway of the satellite, and 2) the vertical dimension of the landsat scene. The expected center of each scene is given corresponding Path and Row numbers. These path/row numbers can then be used as a reference grid for identifying and selecting Landsat scenes. The WRS-1 was used for the Landsat 1 through 3 satellites. WRS-2 is used for Landsat 4 through 7. For more information see



Having very little moisture; tolerating or adapted to dry conditions. 1



An animal approximately one year of age. A short yearling is from 9-12 months of age and a long year- ling is from 12-18 months. 1

Yearlong Grazing*

Continuous grazing for a calendar year. 1

Yearlong Range*

Range that is, or can be, grazed yearlong. 1

Yellow Edge

Remote sensing term for the portion of the electromagnetic spectrum corresponding to yellow visible light (roughly between 580 and 625 nanometers). Yellow-edge wavelengths are useful for classifying different types of vegetation.


(1) the quantity of a product in a given space and/or time. (2) The harvested portion of a product. Syn. production, total annual yield or runoff 1


Zoning (Rural)*

A means by which governmental authority is used to promote the proper use of land under certain circumstances. This power traditionally resides in the state, and the power to regulate land uses by zoning is usually delegated to minor units of government, such as towns, municipalities, and counties, through an enabling act that specifies powers granted and the conditions under which these are to be exercised.1

Glossary References

glossary/home.txt · Last modified: 2014/10/22 15:54 by gtucker