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Trails, Greenway, and Outdoor Recreation Terms

Compiled and edited by Jim Schmid

Contact the editor if you have terms and definitions to add to this glossary

Compiled and edited by Jim Schmid

Many of the glossary terms and definitions provided here were compiled for and published in Trails Primer: A Glossary of Trails, Greenway, and Outdoor Recreation Terms and Acronyms, 2001, Jim Schmid, editor, South Carollina Department of Parks, Recreation and Tourism, Columbia, SC.

The terms are listed in alphabetical order, so definitions of interest can be found quickly.

A | B | C | D | E | F | G | H | I | J | K | L | M | N | O | P | Q | R | S | T | U | V | W | X | Y | Z

The definitions clearly point to the intersection of trails and greenway work with numerous other disciplines and professions. I think that everyone involved with trails and greenway development will find that this is not just a useful list of terms. Spending some time with this list will provide quite an education about the various professions and their terminology.

This does not pretend to contain the most exhaustive list of terms or the best, most acceptable, or locally appropriate definitions. Ideally, you will create something new and more suitable by editing and improving upon the definitions found here. The end result of this work is a starting point�a list of terms that will get trail managers and advocates thinking about and sharing definitions.

The terms range from the mundane to the highly technical. The definitions have been taken primarily from glossaries and terms found in dozens of trail and greenway publications published in the last forty years. This glossary can be read quickly, understood easily, and applied immediately. I hope that this will be a valuable resource for all who work to develop trails and greenways.

The beginning of wisdom is calling things by their right names. �CHINESE PROVERB

"A" Horizon: The surface horizon of a mineral soil having maximum biological activity, or eluviation (removal of materials dissolved or suspended in water), or both.

Abandonment: As used by railroad companies means to cease operation on a line, or to terminate the line itself. In some instances termination includes the removal of the rails and ties for use in other areas or for sale as scrap.

Abney Level: Hand-held instrument that is adjusted like a sextant and can be set to a fixed gradient. The user sights through the Abney to a fixed reference (usually a second person) until the crosshair bisects the bubble, this indicates the preset grade.

Abutment: Structure at either extreme end of a bridge that supports the superstructure (sill, stringers, trusses, or decks) composed of stone, concrete, brick, or timber.

Access: The opportunity to approach, enter, or make use of public lands.

Access Points: Designated areas and passageways that allow the public to reach a trail from adjacent streets or community facilities.

Access Trail: Any trail that connects the main trail to a town, road, or another trail system.

Accessible: A term used to describe a site, building, facility, or trail that complies with the Americans with Disabilities Act (ADA) Accessibility Guidelines and can be approached, entered, and used by people with disabilities.

Accessible Route: A continuous, unobstructed path connecting all accessible elements and spaces of a facility or building that meets the requirements of ADAAG.

Acclimatization: The gradual process of becoming physiologically accustomed to high altitude.

Acquisition: The act or process of acquiring fee title or interest of real property.

Acre: A measure of area equal to 43,560 square feet. One square mile equals 640 acres.

Acute Mountain Sickness (AMS): A condition characterized by shortness of breath, fatigue, headache, nausea, and other flu-like symptoms. It occurs at high altitude and is attributed to a shortage of oxygen. Most people don't experience symptoms until they reach heights well above 5,000 feet.

Ad Valorem Tax: A special tax levied to raise funds for a particular purpose of recognized value to the community. Adaptive Management: A formal process for continually improving management policies and practices by learning from the outcomes of operational programs and new scientific information. Under adaptive management, plans and activities are treated as working hypotheses rather than final solutions to complex problems. This approach builds on common sense, experimentation, and learning from experience, which is then used in the implementation of plans. The process generally includes four phases: planning, implementation, monitoring, and evaluation.

Adaptive Management (Adaptive Ecosystem Management): A formal process for continually improving management policies and practices by learning from the outcomes of operational programs and new scientific information. Under adaptive management, plans and activities are treated as working hypotheses rather than final solutions to complex problems. This approach builds on common sense, experimentation, and learning from experience, which is then used in the implementation of plans. The process generally includes four phases: planning, implementation, monitoring, and evaluation.

Adit: A nearly horizontal passage in an underground mine, driven from the surface, by which a mine may be entered, ventilated, or dewatered.

Adopt-A-Trail: A program in which groups or businesses "adopt" trails, providing volunteer work parties at periodic intervals to help maintain the trail. Though no special trail privileges are granted, the trail manager generally acknowledges that a trail has been "adopted" by erecting signs that indicate the trail is part of an Adopt-A-Trail program and include the name of the adopter.

Adverse Visual Impact: Any modification in land forms, water bodies, or vegetation, or any introduction of structures, which negatively interrupts the visual character of the landscape and disrupts the harmony of the basic elements (i.e., form, line, color, and texture).

Advocacy: The process of influencing government to bring about desired changes; to be in support of something.

Adz (Adze): An ax-like tool for dressing wood.

Aerobic: An intensity of exercise that allows the body's need for oxygen to be continually met. This intensity can be sustained for long periods.A nearly horizontal passage in an underground mine, driven from the surface, by which a mine may be entered, ventilated, or dewatered.

(A)esthetics: Relates to the pleasurable characteristics of a physical environment as perceived through the five senses of sight, sound, smell, taste, and touch.

Aggradation (Aggrade): The geologic process by which streambeds are raised in elevation and flood plains are formed due to sediment deposition. Opposite of degradation.

Aggregate: Material made up of crushed stone or gravel used as a base course for riprap, asphalt, or concrete pavement. Aggregate is also used in asphalt and concrete mixes.

Aggregate (of Soil): Many fine soil particles held in a single mass or cluster, such as a clod, crumb, block, or prism. Many properties of the aggregate differ from those of an equal mass of unaggregated soil.

Aiming Off: The technique of purposefully erring to one side when following a compass bearing. Always try to go around obstacles on one side. When you arrive at a baseline, you will know in which direction to look for your intended destination.

Alignment: The layout of the trail in horizontal and vertical planes. The bends, curves, and ups and downs of the trail. The more the alignment varies, the more challenging the trail.

All-Terrain Vehicle (ATV): A wheeled or tracked vehicle, other than a snowmobile or work vehicle, designed primarily for recreational use or for the transportation of property or equipment exclusively on trails, undeveloped road rights-of-way, marshland, open country, or other unprepared surfaces.

Allotment: An area of land where one or more individuals graze their livestock. An allotment generally consists of federal rangelands, but may include intermingled parcels of private, state, or federal lands. BLM and Forest Service stipulate the number of livestock and season of use of each allotment.

Alluvial: Pertaining to material that is carried and deposited by running water.

Alluvial Fan: A low, outspread, relatively flat to gently sloping mass of loose rock material deposited by a stream where it flows from a narrow mountain valley onto a plain or broad valley.

Alluvium: Sand, mud, and other sediments deposited on land by streams.

Alpine Start: Predawn departure from camp in order to reach a summit before snowmelt becomes problematic.

Alternate Line: Intentional design of trails to provide users with options in alternative routes.

Altimeter: An instrument for measuring altitude.

Altitude: The height of a thing or place measured Above Ground Level or from Mean Sea Level.

Amenities: Any element used to enhance the user's experience and comfort along a trail.

Americans with Disabilities Act of 1990 (ADA): A federal law prohibiting discrimination against people with disabilities. Requires public entities and public accommodations to provide accessible accommodations for people with disabilities.

Americans with Disabilities Act Accessibility Guidelines (ADAAG): Design guidelines for providing access to a range of indoor and outdoor settings by people with disabilities.

Anaerobic: An intensity of exercise above that at which the body's need for oxygen can be continually met. This intensity can be sustained only briefly.

Anaphylactic Shock: An extreme allergic reaction in some people (caused by the body producing to much histamine) when stung by bees, wasps, yellow jackets, etc. Reactions include red skin, itchy hives, and the closing of the airways. If susceptible to anaphylaxis it would be wise to carry an Anakit prescribed by your doctor.

Anchor (Keystone, Gargoyle, Corral Rock, Corralling, Dragon's Tooth, Shepherd): Large stone that holds other stones and/or soil in place. An object, such as a stone, that defines the sides of a trail, helping to keep users in the center of the tread. A tree or rock used to hold (anchor) one end of a winch or come-along stationary while it pulls on another object.

Angle: Angle is measured with a straight vertical as 90� and a straight horizontal as 0�. A grade of 100% would have an angle of 45�.

Angle of Observation: The angle, both vertical and horizontal, between a viewer's line of sight and the landscape being viewed. Anorak: Wind-proof jacket with hood attached.

Angle of Repose: The steepest slope angle (measured from the horizon) at which material will rest without moving or sliding down the slope. Loose material would slide across the trail or roll downhill at any steeper angle. For large blocky rocks, the angle of repose will be much higher than for sand or small round rocks.

Anorak: Wind-proof jacket with hood attached.

Apex: The sharpest part of a turn, where the transition from entering to exiting takes place.

Appraisal: An estimate and opinion of value, usually a written statement of the market value of an adequately described parcel of property as of a specified date.

Apron: One of the three main elements of a waterbar. It catches water running down the trail and directs it off. Apron is also the transition area on a switchback (also called the "landing").

Aquatic Habitat: Areas associated with water that provide food and shelter and other elements critical to completion of an organism's life cycle. Aquatic habitats include streams, wetlands, marshes, bogs, estuaries, and riparian areas, as well as large fresh and salt-water bodies.

Aquifer: Underground bodies of water. There are two types of aquifers. Open aquifers have permeable materials overlying them, e.g. soil with underlying loose gravel. Closed aquifers are capped with an impervious layer of material, such as clay, which prevents water from penetrating from the soils directly above. The water level in aquifers rises and falls in response to water removal and infiltration.

Arborist: An individual trained in arboriculture, forestry, landscape architecture, horticulture, or related fields and experienced in the conservation and preservation of native and ornamental trees.

Archaeological Resources (Cultural, Heritage): Any material of past human life, activities, or habitation that are of historic or prehistoric significance. Such materials include, but are not limited to, pottery, basketry, bottles, weapon projectiles, tools, structures, pit houses, rock paintings, rock carvings, graves, skeletal remains, personal items and clothing, household or business refuse, or any piece of the foregoing.

Archaeological Site: A concentration of material remains of past human life or activities that is of historic or prehistoric significance and that has been surveyed by a qualified archeologist.

Area of Critical Environmental Concern (ACEC): Acreage within public lands where special management attention is required (when such areas are developed or used or where no development is required) to protect and prevent irreparable damage to important historical, cultural, or visual values, fish and wildlife resources, or other natural systems or processes, or to protect life and safety from natural hazards. The identification of a potential ACEC shall not, of itself, change or prevent change of the management or use of public lands.

Ar�te: French term for a narrow or pointy spot on a ridge.

Arid: A climate or region in which precipitation is deficient in quantity or occurs infrequently.

Armoring: Reinforcement of a surface with rock, brick, stone, concrete, or other "paving" material.

Artifacts: Any object made, modified, or used by humans.

Ascent: An upward slope or incline or process of rising or going upward.

Ascent, First: A much-coveted prize; first to climb a certain peak or climbing route.

Aspect: The particular compass direction a trail or site faces. Aspect affects the amount of solar radiation and year-round moisture to which a site is subjected.

Asphalt (Macadam, Asphaltic Concrete): Petroleum-based flexible surface material that provides a smoothly paved surface suitable for bicycles and in-line skates. It is preferred in urban areas where trails are often used for commuting to and from work or school.

Assessment, Trail or Corridor: Physical assessments undertaken to better understand a trail or corridor. Assessments include an accurate description and documentation of native elements and an inventory of built structures along the trail or corridor.

At-Grade Crossing: A trail crossing a roadway on the same elevation. Ideally, a safe at-grade crossing has either light automobile traffic or a traffic signal that can be activated by trail users.

Attractive Nuisance: Something on a trail or greenway that attracts users and that is potentially dangerous to them, such as a mineshaft without a fence around it.

Axe (Ax): A tool with a long handle and bladed head (single bit-- one sharp side or double bit-- two sharp sides) for chopping deadfall from trails, shaping stakes for turnpikes and waterbars, and cutting notches for structures made of timber.

"B" Horizon: A soil horizon, usually beneath an A horizon, or surface soil, in which 1) clay, iron, or aluminum, with accessory organic matter, have accumulated by receiving suspended material from the A horizon above it or by clay development in place; 2) the soil has a blocky or prismatic structure; or 3) the soil has some combination of these features. In soils with distinct profiles, the B horizon is roughly equivalent to the general term "subsoil.

Backcountry: An area where there are no maintained roads or permanent buildings�just primitive roads and trails.

Backcut: The vertical part of a bench cut that is blended into the backslope.

Backfill: Material used to refill a ditch or other excavation, or the process of doing this action.

Backpack (Backpacking): A large pack worn on the back to carry camping supplies. To go on an overnight hike carrying your supplies in a backpack.

Backramp: An angled diversion dam or earthen wall leading out of the center of a drainage dip. Serves as a backup to change direction of water flow if needed.

Backslope (Cutslope, Cutbank, Backcut): The cut bank along the uphill side of the trail extending upward from the tread. Usually sloped back by varying degrees, depending on bank composition and slope stability.

Bail (Bail Out): To abort (perhaps temporarily) one's planned or intended workday or outdoor trip, often due to injury or change in weather conditions.

Balaclava: A form-fitting hood (fleece, wool, or synthetic) that covers not only the head but also the face and neck, it can be worn as a cap or pulled down over the ears to protect your face from wind.

Bald: Mountain with an open, grassy summit that's void of trees.

Ballast: Stone, cinders, gravel, or crushed rock fill material used to elevate a railroad bed above the surrounding grade. It drains water away from the ties, spreads the track load over softer subgrade, provides an even bearing for ties, holds ties in place and checks the growth of grass and weeds.

Baluster: One of many vertical pieces between the top and bottom rails of a guardrail.

Bandanna: A square of cloth, usually cotton, with many more uses than just a scarf.

Bank (Embankment, Stream Bank): The part of the soil next to a stream, lake, or body of water where the soil elevation adjacent to the water is higher than the water level.

Bar: A sand or gravel deposit in a streambed that is often exposed only during low water periods.

Bark Spud: A tool with a 1- to 4-foot long wood handle and a dished blade used to remove bark from logs by sliding between the bark and the wood.

Barricade: A portable or fixed barrier having object markings, used to close all or a portion of the trail right-of-way to traffic.

Barrier: A structure installed to protect an environmentally sensitive area. A barrier can be hard (fence); live (planted); a combination of hard and live; or a terrain feature (berm). A barrier can be physical (obstructing passage) or psychological (deterring access).

Barrier-Free Design: A trail design that promotes the elimination of physical barriers that reduce access by people with disabilities.

Basalt: The commonest type of solidified lava; a hard, dense, dark gray fine-grained igneous rock, often having a glassy appearance.

Base: The primary excavated bed of a trail upon which the tread, or finished surface lies.

Base Camp: A semi-permanent camp set up after traveling into an area from which day trips for trail work or enjoyment can be made. This allows you to leave heavy gear in one place for several days.

Base Course: The layer or layers of specified material of designed thickness placed on a trailbed to support surfacing.

Base Layer: The layer of clothing closest to the skin.

Base Map: A map showing the important natural and built features of an area. (Such maps are used to establish consistency when maps are used for various purposes.)

Baseline: A line of reference crossing your path of travel used to make following a compass bearing closer to foolproof. Baselines include roads, powerlines, railroad tracks, and rivers. If you are heading to a bridge over a river, set the compass bearing for the bridge. If you are off by several degrees, you will arrive at your baseline of the river, knowing that you need to look for the bridge.

Basic Elements: The four design elements (form, line, color, and texture) which determine how the character of a landscape is perceived.

Batter (Battering): The angle at which an abutment or rock/timber wall is inclined against the earth it retains. The process of sloping the exposed face of a wall back either at a uniform angle, or stepping it back uniformly.

Bead: In a tire, the edge along each inner circumference that fits into the rim.

Bear Bag (Bear-bagging): Practice of suspending a food bag in a manner meant to protect it from bears, on a sturdy limb at least fifteen feet from the ground and at least six feet from the trunk.

Bear Bells: Safety device worn by hikers to alert bears of their presence.

Bearing, Compass: The direction of travel from one point to another. The first point is always true north (or magnetic north if your compass has not been adjusted for declination). A bearing of 90 degrees is to travel directly east. You can also "take a bearing" on an object to see in which direction it lies in relation to your location.

Bed: The primary excavated surface of a trail upon which the tread or finished surface lies. Also the bottom of a channel, creek, river, stream, or other body of water.

Bedrock: Solid rock material underlying soils and other earthy surface formations.

Belay: Securing a climber by using a rope through one or more fixed anchors usually held by two people.

Belayer: The person controlling the tension of the rope that is securing a climber.

Bench: A long seat (with or without a back) for two or more people.

Bench Cut: A relatively flat, stable surface (tread) on a hillside occurring naturally or by excavation. When excavated often referred to as full, half, or partial bench.

Bench, Full: Where the total width of the trail tread is excavated out of the slope and the trail tread contains no compacted fill material.

Bench, Half: Where half the width of the trail tread is excavated out of the slope and the outside of the trail tread contains the excavated and compacted material.

Bench, Partial: Where part of the width of the trail tread is excavated out of the slope and the rest of the trail tread is made up of fill material.

Bench Mark: A metal disk set into the ground for use as an exact reference point by surveyors. Bench marks are indicated on a topographic map with an X and the letter BM with an elevation next to it.

Benefits-Based Approach: An approach to evaluating the delivery of park, recreation, and trail resources, facilities, and services which focuses on identifying the economic, environmental, and social benefits specifically and directly attributable to the cost of providing the opportunities from which the benefits are derived.

Bent: Structural member or framework used for strengthening a bridge or trestle transversely.

Bentonite: A clay mineral formed from the decomposing of volcanic ash. Commonly Bentonite can readily absorb water.

Bergschrund: Crevasse that separates flowing ice from stagnant ice at the head of a glacier.

Berm: The ridge of material formed on the outer edge of the trail that projects higher than the center of the trail tread. When improperly designed or unintentionally caused by tread compaction and soil displacement during trail use, a berm can trap water on the trail and lead to erosion.

Best Management Practices (BMPs): A suite of techniques that guide, or may be applied to, management actions to aid in achieving desired outcomes. Best management practices are often developed in conjunction with land use plans, but they are not considered a land use plan decision unless the land use plan specifies that they are mandatory. They may be up-dated or modified without a plan amendment if they are not mandatory.

Bevel: Finishing the corner of a piece of lumber by removing a narrow portion of wood at a uniform angle to the edge and face. A bevel follows the grain of the wood. A surface that meets another surface at any angle other than 0 or 90 degrees.

Bicycle (Bike): A vehicle having two tandems wheels, propelled solely by human power, upon which a person or persons may ride.

Bicycle, BMX: Riser handlebar, heavy-duty, reinforced frame and fork, and 20-inch 48-spoke wheels.

Bicycle, City: A hybrid equipped with accessories like fenders, rack, etc.

Bicycle, Cross: Similar to a road bike, except wider tires and cantilever brakes. With a skilled rider in mind, designed for riding off-pavement.

Bicycle, Cruiser: Wide, sweeping handlebars, wide saddle, and balloon tires.

Bicycle, Folding: Hybrid features, but with a hinged frame and stem.

Bicycle, Freeride (Hucking): Heavy-duty reinforced frame, wide tires, riser handlebars, double-crown, triple-clamp suspension forks, and disc brakes. For aggressive riding on rough surfaces and jumping.

Bicycle, Hybrid: Flat handlebars like a mountain bike, but with 700c wheels like a road bike.

Bicycle, Juvenile: Smaller bikes designed for kids but also fitting smaller adults.

Bicycle, Mountain (Mountain bike, All-Terrain Bicycle): Wide tires, flat handlebars, low gearing, and direct pull or disc brakes. For riding on rougher surfaces. Front suspension, or front and light-weight rear suspension.

Bicycle, Road: Drop or triathlon handlebars, caliper brakes, and 700c wheels with 20-25c tires.

Bicycle, Tandem: Built for two, with either drop road handlebars or flat handlebars as on a hybrid.

Bicycle, Touring: Similar to a road bike, except with direct-pull brakes and wider tires. Designed for self-contained touring.

Bicycle/Pedestrian Coordinator: A position responsible for planning and managing nonmotorized facilities and programs, creating safety and promotional materials that encourage bicycle and pedestrian transportation, and serving as the principal liaison between government transportation entities, the press, citizen organizations, and individuals on bicycling and walking issues.

Bicycle Friendly Area(s): An area that provides compatible and safe streets for bicyclists. These areas are designated with a comprehensive sign program that alerts motorists or shared bicycle use along roadways. Bike lanes may or may not be used in BFAs depending on site constraints. Typically, BFAs are used in residential neighborhoods, although these areas could be used in any type of development where designated bike lanes are not required, but motorists should be aware of bicyclists using the roadways.

Bike Lane: A portion of a roadway that has been designated by striping, signing, and pavement markings for the preferential or exclusive use of bicyclists.

Bike Path (Shared Use Path, Bicycle Path, Bike Trail, Multi-use Path/Trail): Any corridor that is physically separated from motorized vehicular traffic by an open space or barrier, and that is either within the highway right-of-way or within an independent right-of-way. Besides bicycles these paths may also be shared by pedestrians, skaters, wheelchair users, joggers, and other non-motorized users. The term bicycle path is becoming less common, since such facilities are rarely used exclusively by bicyclists.

Bike Route: A shared right-of-way located on lightly traveled streets and roadways designated with appropriate "bike route" directional and informational signs. These signs help encourage use, and warn motorists that bicycles may be present.

Bikeway(s): Any road, path, or way which in some manner is specifically designated as being open to bicycle travel, regardless of whether such facilities are designated for the exclusive use of bicycles or are to be shared with other transportation modes.

Biodegradable: Able to decompose when exposed to biological agents and soil chemicals.

Biodiversity: The variety and variability within and among living populations and species of organisms and the ecosystems in which they occur.

Biological Assessment: In general, a documented review of programs or activities in sufficient detail to determine how an action or proposed action may affect any Federally listed threatened or endangered wildlife, fish, or plant species. Specifically, a procedural step in the interagency consultation process under the Endangered Species Act, Section 7, where the BLM submits a written summary of potential project impacts to threatened or endangered species to the USF&WS for their evaluation.

Biological Soil Crusts: Bryophytes, lichens, cyanobacteria, algae, and mocfungi which exist on or just below the soil surface in arid and semi arid plant communities throughout the world. Biomass: The total amount of living material, plants and animals, above and below the soil surface in a biotic community.

Biotic Communities: The assemblage of native and exotic plants of a particular site or landscape, including microorganisms, fungi, algae, vascular and herbaceous plants, invertebrates, and vertebrates. These assemblages and their biotic and abiotic relationships serve landscape and watershed functions by promoting soil properties supporting water infiltration, recycling and transfer, species survival, and sustainable population dynamics.

Birdcage: Wire rope that has begun to unwrap individual strands of wire.

Bivouac: The site where a tent is set up. To spend a night out without a tent.

Bivouac Sack (Bivy Sack): A lightweight, unfilled, waterproof bag that can cover a sleeping bag.

Blaze: A trail marker. Blazes can be made on a tree by scraping away some of the bark and painting a 2-inch by 6-inch vertical rectangle. Plastic or metal triangles or diamonds (known as blazes) with the name of the trail or a directional arrow imprinted can be purchased and nailed to trees or posts to mark a trail route.

Blaze, Blue: The color often used to paint blazes that mark side trails to a campsite or a town off main trails such as the Appalachian Trail. Many other trails follow the Appalachian Trail example.

Blaze, Blue: When used as a verb it means to take trails other than the official trail you are on because they offer a shorter or easier alternative to your route.

Blaze, Double (Offset Blazes): Two blazes (vertical alignment) that denote a change in direction or junction in the trail ahead. Usually the top blaze is offset in the direction of the turn.

Blaze, White: White blazes are generally used to mark a main or trunk trail such as the Appalachian Trail.

Blazer, Black: Someone who removes or paints over trail markers.

Blazer, Blue: Thru-hiker who shortcuts the main trail by using connectors and bypasses.

Blazer, Yellow: A long-distance trail user taking to the road instead of sticking to the trail.

Bleeder (Kick Out, Diversion Dip): Graded depression angled to drain water sideways off the treadway.

Bleeder: Trail that begins in promising shape but inexplicably vanishes.

Blister: A thin, round swelling of the skin, filled with fluid, caused by rubbing.

Block: Pulley in which a rope or cable is thread through.

Block, Snatch: Pulley with hinged side plate that opens allowing attachment anywhere along a fixed rope.

Blowdow: Trees toppled over by high winds.

Blowout: An area from which soil material has been removed by wind. Such an area appears as a nearly barren, shallow depression with a flat or irregular floor consisting of a resistant layer, an accumulation of pebbles, or wet soil lying just above a water table.

Blueway(s): River and stream corridors of protected open space used for conservation and recreation purposes. They protect natural, historical, cultural, and recreational resources and preserve scenic landscapes.

Bluff: A steep headland, riverbank, or cliff.

BMX (Bicycle Motocross): Refers to both the sport and to the bicycle, which has 20-inch wheels and single speed.

Board Feet: A unit of solid wood one foot square and one inch thick.

Boardwalk: An elevated, fixed-planked structure, usually built on pilings in areas of wet soil or water to provide dry crossings.

Bog(s): A mucky or peaty surface soil underlain by peat where little direct sunlight reaches the trail, or where there are flat areas that are difficult to drain.

Bollard: A barrier post, usually 30 to 42 inches in height, used to block vehicular traffic at trail access points. Should be installed in odd numbers (one or three). Also an electric light post found alongside trails.

Bonk: When muscles completely run out of fuel and you're tired. Can be cured by consuming carbohydrate-rich foods.

Borrow: Fill material required for on-site trail construction and obtained from other nearby locations.

Borrow Pit: Area where soil, gravel, or rock materials are removed to be used on the trail for tread, embankments, or backfilling.

Boulder: A large substrate particle that is larger than cobble.

Boulder (Bouldering): Basic or intermediate climbing carried out on relatively small rocks that can be traversed without great risk of bodily harm in case of a fall.

Bow Saw: A 16-, 21-, or 36-inch thin bladed saw with a curved handle used to cut brush or trim small branches.

Bridge: A structure, including supports, erected over a depression (stream, river, chasm, canyon, or road) and having a deck for carrying trail traffic. If the bridge is over two feet above the surface, it should have railings.

Bridleway (Bridle Path): Public way designed and maintained primarily for equestrian use. Other nonmotorized uses may be permitted.

Broadcast(ing): Leave No Trace principle of scattering soil, debris, or wastewater over a wide area to keep the area as natural looking as possible after camping.

Broadcasting (Broadcast): Process of widely distributing excavated soil, cut branches, and duff as far downhill or uphill and away from the new tread as possible. Widely distributing so as to blend in with the natural soil contours and vegetation and be as inconspicuous as possible.

Brook: A small natural stream of water.

Brownfield(s): Abandoned, idled, or under-used commercial, industrial, or institutional properties, where investment for redevelopment or reuse is discouraged by the presence of light to moderate contamination from hazardous substances.

Brush: Vegetation or small flora.

Brush Hook (Bank Blade): These tools are used for clearing brush, briar, or undergrowth too heavy for a scythe and not suited for an ax. The Brush Hook with a 36-inch handle and 12-inch hooked blade (sharpened on one side) cuts easily on the "pull" stroke. The Bank Blade is similar to a Brush Hook, but its wide blade is straight and sharpened on both sides.

Brushing: To clear the trail corridor of plants, trees, and branches, which could impede the progress of trail users.

Brushing-In (Obliteration): To pile logs, branches, rocks, or duff along the sides of the tread to keep users from widening the trail; or to fill in a closed trail with debris so that it will not be used.

Bucket(s): Usually a five-gallon plastic container with a heavy wire handle (bail) useful for transporting soil, duff, and small hand tools.

Buffer (Buffer Zone): Any type of natural or constructed barrier (trees, shrubs, or wooden fences) used between the trail and adjacent lands to minimize impacts (physical or visual). Buffers also provide a transition between adjacent land uses.

Bug Dope: Chemical or botanical substance, such as DEET, intended to deter insects.

Bump-up Box (Bounce Box, Leapfrog Box, Floater Box): Box containing supplies that a thru-hiker needs but doesn't want to carry (repair kit, batteries, extra glasses, or excess quantities of stuff such as coffee). It is mailed ahead to next resupply point.

Bunny Hop: A technique in which both wheels (motorcycle or bicycle) leave the ground to ride over obstacles such as rocks or logs.

Bushwhack: Off-trail hiking (originally where the going was difficult, where many bushes had to be whacked). Now it is often used to mean off-trail travel regardless of whether the going is difficult or not.

Bylaws: Set of regulations adopted by a trail or greenway organization that governs the way the organization will do business.

"C" Horizon: The unconsolidated rock material in the lower part of the soil profile that is similar to the material from which the upper horizons (or at least a part of the B horizon) have developed.

Cable, Wire: A thick, heavy rope, made of wire strands.

Cable Fly Zone: The hazardous area a cable can potentially move to when it comes under tension, or is suddenly released from tension.

Cable Gripper: A device that clamps onto a cable when tension is applied to the attachment point.

Cable Strap: A pre-cut length of wire rope (that may have eyes on both ends), which is used in rigging applications.

Cache: A supply of food, water, or tools, usually buried or hidden.

Cadence: The number of times during one minute that a foot completes a pedal stroke on bicycle. Also called pedal rpm.

Cagoule: Long anorak descending below the knees.

Cairn (Duck): A constructed pile of rocks located adjacent to a trail used to mark the route in lieu of a blaze. Often used in open or treeless areas where the tread is indistinct.

Caliche: A broad term for the more or less cemented deposits of calcium carbonate in many soils of warm, temperate areas, as in the southwestern states. When it is very near the surface or exposed by erosion, the material hardens.

Call Box: An emergency telephone system installed along a trail with direct connection to the local 911 network.

Camber: A slight bend in a timber.

Cameling (Cameling Up): Drinking all the water you can while at a water source, so that you minimize the amount of water you need to carry.

Camp (Campsite, Camping): Living outdoors in a tent or trailer while on vacation or as a recreational activity. Site where overnight stays are permitted.

Camp Host (Campground Host): Many regional, state, and federal campgrounds use volunteer camp hosts whose duties can include checking campers in and out, providing information on the park and its resources, and serving as initial contact for campers in emergency situations.

Camping, Stealth: Camping without leaving a trace.

Campsite, Established: Campsite made obvious by devegetated ground.

Canal: An artificial waterway for transportation or irrigation. Canal and irrigation ditch banks are often used as trails.

Canopy: The more or less continuous cover of branches and foliage formed collectively by the crowns of adjacent trees and other woody growth.

Cant: Angular deviation from a vertical or horizontal plane or surface; an inclination or slope. A slope in the turn of a road or track where the outside is higher.

Cant Hook (Peavey): Cant hooks and peaveys afford leverage for moving or rotating logs. To roll a heavy log, use a series of short bits with the hook and maintain your progress by quickly resetting it. Catch the log with the hook hanging on top of the log. Rotate the log using the leverage of the handle, working the tool like a ratchet. Moving large logs may require several hooks working together.

Cantilever: The portion of a beam or plank extending beyond one or both of its supports.

Candidate Species: A plant or animal species designated by the USF&WS as a candidate for listing as threatened or endangered because numbers are declining so rapidly that official listing may become necessary as a conservation measure.

Canvas Bag(s): The canvas bag or coal sack is a large heavy tote bag with two handles that can be used to carry large volumes of light material (up to 90 lbs) such as duff, soil, rocks, or tools. It has the same capacity as about two full buckets.

Capacity (Carrying Capacity): Maximum number of trail users that can pass through a given trail section during a given time period under existing trail conditions. Also refers to the amount of use a given resource can sustain before an irreversible deterioration in the quality of the resource begins to occur.

Cape: A piece of land extending into water.

Carabiner: An oblong metal clip with a spring-loaded gate used to clip slings to ropes or ropes to anchors.

Cardiovascular: Pertaining to the heart, lungs, and blood vessels.

Cartographer: A person who draws or makes maps.

Cascade: A short, steep drop in streambed elevation often marked by boulders and agitated white water.

Cat Hole (Cathole): A hole you dig 6 to 8 inches deep, into which you deposit solid human waste at least 200 feet from water, camp, and trails. Cover and camouflage the cat hole when finished.

Catch Air: What happens when the wheels of a mountain bike, motorcycle, or ATV leave the ground, usually because of a rise or dip in the trail.

Catch Point: The outer limits of a trailway where the excavation and/or embankment intersect with the ground line.

Catchment: The catching or collecting of water, especially rainfall. A reservoir or other basin for catching water.

Categorical Exclusion (CE): A technical exclusion for federal projects that do not result in significant environmental impacts. Such projects are not required to prepare environmental reviews. (NEPA process.)

Cattle Guard: A closely spaced group of horizontal pipes placed in a roadbed at fence line to prevent cattle from escaping and yet allow vehicles free access.

Causeway (Elevated Tread, Raised Tread): Elevated section of trail tread that is raised above the level of the surrounding ground by the placement and compaction of mineral soil or other material contained by rock or log, usually through permanently or seasonally wet areas.

Cave: Any naturally occurring void, cavity, recess, or system of interconnected passages that occurs beneath the surface of the earth or within a cliff or ledge (including any cave resource therein, but not including any mine, tunnel, aqueduct, or other excavation) and which is large enough to serve as cave habitat for wildlife. The term includes any natural pit, sinkhole, or other feature that is an extension of the entrance.

Caving: The collapse of a stream bank by undercutting due to wearing away of the toe or an erodible soil layer above the toe.

Cavity: A hole or hollow place in a tree.

Cement: Binding material used in construction, typically made by heating a mixture of limestone and clay until it almost fuses and then grinding it to a fine powder. When mixed with water, the silicates and aluminates in the cement undergo a chemical reaction; the resulting hardened mass is then impervious to water. It may also be mixed with water and aggregates (crushed stone, sand, and gravel) to form concrete .

Center Line: An imaginary line marking the center of the trail. During construction, the center line is usually marked by placing a row of flags or stakes.

Certificate of Interim Trail Use (CITU): A document issued by the STB in regular (non-exempt) abandonment proceedings where a railroad and a trail manager have expressed a mutual willingness to negotiate a railbanking agreement. It permits interim trail use and allows the railroad to discontinue service, cancel tariffs, and salvage track and materials 30 days after it is issued. It further provides for a 180-day period for negotiation of a final agreement that, if reached, delays the effective date of full abandonment during the period the agreement is in effect.

Certification: The process by which protected sites and segments of national historic (and some national scenic) trails are officially recognized by the administering federal agency. The concept is also used to track completed and recognized segments of some trails.

Chain Saw: A portable, gas-operated saw with a loop chain carrying cutting teeth.

Challenge Park (Terrain Park, Skills Park): A special-use area that features a variety of challenging technical trail features, generally for mountain bicycle or motorized recreation uses.

Chamfer: Similar to a bevel but done at the end of the piece of wood and across the grain.

Channel: An area that contains continuously or periodically flowing water that is confined by banks and a streambed. Also used a verb "to channel" water.

Channelization: The process of changing (usually straightening) the natural path of a waterway.

Characteristic: A distinguishing trait, feature, or quality.

Charrette: An intensive, interactive public design workshop taking place over a few days and in proximity to the site in which designers, property owners, developers, public officials, environmentalists, citizens, and other persons or groups of people work in harmony to achieve an agreeable trail or greenway project. The term is French and means "wagon." It dates from medieval times, when a wagon ("charrette") was sent through the town to pick up projects completed by apprentices in the architects' guild.

Check Point: A landmark that can be easily identified on the ground to let you know when to leave a "handrail" and begin a new course of travel.

Check Step (Retainer Bar): A rock or timber step placed in or across a trail tread and designed to act as both a low dam (to slow water flowing down the trail) and as a step for trail users. A retainer bar is usually longer and larger than a check step.

Chigger (Redbug): The tiny, red larva of certain mites. Bites cause itching and red welts.

Chink: A small fissure or crack; the space between larger rocks used to armor a trail. Also used as a verb: to chink.

Chinking: To fill the crack or space between larger rocks with smaller rocks and soil to stabilize the tread paving.

Chock: Any metal device that is inserted into rock as an anchor.

Choke (Gateway): A slight narrowing in the trail tread usually with rock or logs used to control user speed.

Choker: Loop of rope or cable cinched around a load so it gets tighter, or "chokes" the load under pressure.

Chromated Copper Arsenate (CCA): A well-known wood preservative for boardwalks, decks, and other common trail applications where treated lumber is used.

Circle of Danger: The area surrounding a trail worker that is unsafe due to tool use. The inner (or primary) circle of danger is the area the tool can reach while being used. The outer circle of danger is the area the tool could reach if the trail worker lost control or let go of the tool.

Cistern: A small collection pool constructed from rock or rot-resistant wood to help protect water quality in heavily used areas.

Claim, Patented: A mining operation on public land with an official document conferring a right or privilege to have sole use of that operation.

Claim, Unpatented: A mining operation on public land with no privilege or right of sole use by the claimant(s).

Classification: The designation indicating intended use and maintenance specifications for a particular trail.

Clay: A firm, plastic soil with particles less than 0.002 mm in diameter.

Clean: To ride (motorcycle or mountain bike) a tough section of trail without putting a foot on the ground to prevent yourself from falling over.

Clear-Cut (Clear-cutting): Removal of all trees and shrubs, not just mature growth.

Clearing: Removal of windfall trees, uproots, leaning trees, loose limbs, wood chunks, etc. from both the vertical and horizontal trail corridor.

Clearing Height (Vertical Clearance): The vertical dimension, which must be cleared of all tree branches and other obstructions that would otherwise obstruct movement along the trail.

Clearing Limit: The area over and beside a trail that is cleared of trees, limbs, and other obstructions.

Clearing Title (Curing Defects to Title): Defects in title include such things as mortgages, reversions, liens for payment of work done on the property, or easements across a property, which would otherwise be held in fee simple. Curing means removing these defects (e.g. buying out or condemning the easement or reversion).

Clevis (Shackle): A U-shaped metal piece with holes in each end through which a pin or bolt is run. Used to attach two objects together.

Climbing Turn: A turn which is constructed on a grade of 20% or less when measured between the exterior boundaries of the turn, and which follows the grade as it changes the direction of the trail 120 to 180 degrees.

Clinometer: A hand-held instrument used for measuring percent of trail grade. The user sights through the Clinometer to a reference (usually a second person) and reads the measurement directly from the internal scale.

Clod: A mass of soil produced by digging, which usually clumps together easily with repeated wetting and drying.

Closed: Designated areas or trails where specified trail uses are permanently or temporarily prohibited.

Cluster Zoning (Cluster Development): A local ordinance that encourages a developer to concentrate structures in a multi-unit development project. By clustering the units on a property rather than spreading them out in traditional, evenly sized housing plots, critical open space on the site—stream valleys, wooded areas, wetlands, and dunes—can remain intact. Often this open space is commonly owned and held jointly in undivided shares.

Cobble (Cobblestone, Baby Heads): Loose rock, with rounded edges, generally 3-12 inches in diameter used to pave trail tread. Can be further classified as small or large cobble.

Code of Federal Regulations (CFR): The official, legal tabulation or regulations directing federal government activities.

Col: A pass between two mountain peaks; or a low spot in a mountain ridge.

Collaboration: Cooperative process in which interested parties, often with widely varied interests, work together to seek solutions with broad support for managing public or other lands and trails.

Colluviums: Mixed deposits of soil material and rock fragments near the base of steep slopes. Deposits accumulate through soil creep, slides, and local wash.

Come-along (Ratchet Winch): A strong cable fitted with a ratchet to gain mechanical advantage for moving heavy objects over the ground with comparative ease. It is often used in trail work to move large rocks or bridge timbers.

Committee, Ad Hoc (Task Force): Are generally appointed when there is a specific job to be done. When the job is done, the ad hoc committee or task force cease to exist.

Committee, Citizen Advisory: These committees include only citizen members, often appointed. They can be either permanent or established on an as-needed basis for a specified task or time frame.

Committee, Permanent/Standing: They can provide a type of "institutional memory" and an ongoing pool of resources for bringing issues and ideas to the attention of staff and decision-makers. They are not only involved in planning but also in implementing projects.

Committee, Technical Advisory: These are usually staff committees that include representatives of departments involved in planning and implementing trail or greenway programs.

Compacted: The degree of soil consolidation that is obtained by tamping with hand tools or, or heavy equipment.

Compaction: The compression of aggregate, soil, or fill material into a more dense mass by tamping with hand tools or heavy equipment.

Compass: A direction-indicating device that is used with a map to plot a route or check your position.

Competitive Bidding: The process whereby construction projects are required to be advertised and awarded to the lowest responsible and responsive bidder in an open bidding process.

Competitive Use: Any formally organized or structured use, event, or activity in which there are the elements of competition between two or more contestants, registration of participants, and/or a predetermined course or area is designated.

Concessionaire: A person or business that contracts with a trail operating agency (public or private) to operate a facility or over a service.

Concessions: Facilities or services that are leased out to entities other than the trail operator, i.e., sale of food and beverages, accessories, equipment, guided trips, and souvenirs of use or interest to trail users.

Concrete: A composition of coarse and fine aggregates, Portland cement, and water, blended to give a hard, unyielding, nearly white pavement, which can be finished to any degree of smoothness. Color is sometimes added. Concrete is most often used in urban areas with anticipated heavy trail use, or in areas susceptible to flooding.

Condemnation: The taking of private property by government for public use, when the owner will not relinquish it through sale or other means; the owner is compensated by payment of market value. The power to take the property is based on the concept of eminent domain.

Conductive Heat Loss: Occurs when the body loses heat to the air, water, or fabric that is in contact with the body at a lower temperature. Falling into cold water, for example, can cause you lose all your body heat to the water.

Conflict, Recreational: A negative experience occurring when competition for shared resources prevents expected benefits of participation from accruing to an individual or group.

Conflict Resolution: Resolution is an outcome that develops from complete analysis and meets the needs of all concerned parties. Inherent in the process is clear and open communication, mutual respect, shared exploration, an orientation to collaborative problem solving, and a commitment to resolution.

Confluence: The act of flowing together; the meeting or junction of two or more streams; also, the place where these streams meet. The stream or body of water formed by the junction of two or more streams; a combined flood.

Conifer: A tree comprising a wide range of trees that are mostly evergreens. Conifers bear cones (hence, coniferous) and have a needle-shaped or scale-like leaves.

Connectivity: The ability to create functionally contiguous blocks of land or water through linkage of similar native landscapes; the linking of trails, greenways, and communities.

Connectors: Paths or on-road routes in heavily built environments that provide key connections between or within trail or greenway corridors; often, links from subdivisions or neighborhoods to main trails.

Conservancy: A non-profit, privately funded organization whose purpose is to acquire lands for conservation of natural elements.

Conservation: Controlled use and protection of natural resources. The process or means of achieving recovery of variable populations.

Conservation Area: Designated land where conservation strategies are applied for the purpose of attaining a viable plant or animal population.

Conservation Strategy: A management plan for a species, groups of species, or ecosystem that prescribes standards and guidelines that, if implemented, provide a high likelihood that the species, groups of species or, ecosystem, with it's full complement of species and processes, will continue to exist well-distributed throughout a planning area, i.e. a viable population.

Construct (Construction): Building a trail or structure where none previously existed.

Construction, New: A project in which an entirely new trail or facility is built or where a new trail or facility is added to an existing one.

Consumptive Use: A use of resources that reduces the supply.

Contaminate: To make impure or unclean by contact or mixture.

Contour Line (Contour): A line on a topographic map connecting points of the land surface that have the same elevation.

Contracting Officer (CO): An agency official with the authority to enter into, administer, and/or terminate contracts and make related determinations and findings.

Control Point(s) (targets): Places that influence where a trail goes. These features should be flagged and used to help layout a trail. The beginning and end of a trail are basic control points. Other control points include parking areas, trailheads, structures, slopes for turns or switchbacks, road or water crossings, and other trails.

Control Point, Negative: Are places you want users to avoid.

Control Point, Positive: Are places you want trail users to visit.

Convective Heat Loss: This most common form of heat loss occurs when air and water come into contact, or near-contact, with your body and carry heat away with them.

Conveyance: A written instrument by which a title, estate, or interest in property is transferred.

Cooperative Agreement: A negotiated agreement between an agency and one or more parties. Such agreements usually involve funds passing to the non-agency partner.

Corduroy: A rustic form of puncheon using native logs (3 to 5 feet in length) laid parallel on wet saturated ground and covered with a tread of soil. Corduroy typically rots out quickly.

Corral: A pen or enclosure for confining or capturing livestock.

Corralling: The act of placing anchors on the trail to define the sides and emphasize the turns, keeping users on the tread.

Corridor, Scenic: Land set aside on either side of a trail to act as a buffer zone protecting the trail against impacts such as logging or development, which would detract from the quality and experience of a trail.

Corridor, Trail: The full dimensions of the trail, including the area (2 to 3 feet) on either side of the tread and the space overhead (10 to 12 feet) from which brush and obstacles need to be cleared. The area of passage of the trail, including all cleared and managed parts above, below, and adjacent to the tread.

Corridor, Utilitarian: Linear built features which have a primary utilitarian purpose but which may also serve as connections for recreational, cultural, or natural needs.

Counter, Trail-Traffic: Used to gather numbers of individuals or groups using a trail. The three most commonly used types of trail-traffic counters are loop-type, photoelectric, and seismic sensor plate counters.

Counter, Loop-Type: A large loop (approximately 8" by 48") is concealed under a layer of earth in the center of the trail; impulses triggered by users passing over the loop are stored as counts in the unit's memory device.

Counter, Photoelectric: Consists of a scanner that emits an infrared beam, and a reflector that returns the beam to the scanner; the counter is advanced when the beam is interrupted (active infrared detection), or if the sensor detects body heat and motion (passive infrared).

Counter, Seismic Sensor Plate: Pressure-sensitive sensor plates or mats are buried in the trail; wires are connected to the counter unit concealed off-trail. The counter must be adjusted for both sensitivity and length of delay between readings; to avoid multiple counts for people, horses, or groups.

Countersink(ing): Drilling a wide, shallow hole in a piece of wood for a washer and nut or for the head of a bolt or screw. This allows the hardware to be recessed below the surface of the wood.

Course (Tier, Foundation): A single layer of building material of a uniform height. The material is placed one layer (course) at a time on top of another layer (course) to form a foundation, intermediate layer, or cap layer. Materials laid in courses include bricks, concrete blocks, timbers, stone, and logs.

Cover, Ground: Vegetation or other material providing protection to a surface; area covered by live above ground parts of plants.

Cradle Timber: A mid-span timber used to transfer the load of the bridge to the truss system.

Crampon(s): Spikes that attach to the soles of boots, for traveling on hard snow or ice.

Creek: Those areas where surface waters flow sufficiently to produce a defined channel or bed.

Creep: Slow mass movement of soil down relatively steep slopes, primarily by gravity and water.

Crevasse: A deep fissure, as in a glacier; a chasm. A crack or breach in a dike or levee.

Critical Point (Critical Edge, Outside Edge, Lower Edge, Shoulder, Daylight Edge, Toe): The rounded outside edge of the trail tread where water travels off the tread and drains onto the native slope below. It's where trail maintenance problems (usually related to drainage) begin.

Crook: A defect in a log caused by being lumbered from a crooked tree.

Cross-Country Travel (Off-Trail Travel): Hiking or riding across open country rather than on a trail.

Cross Section (Typical Cross Section or Typical, Profile): Diagrammatic presentation of a trail or path profile, which is at right angles to the centerline at a given location.

Crossing, Grade-Separated: Overpasses or tunnels that allow trail users to cross a railroad right-of-way or street at a different level than trains or traffic.

Crosscut Saw: A long saw that was favored a century ago by loggers felling trees. Used today in federally designated Wilderness Areas, or by those who prefer not to use chainsaws.

Crosswalk (Crossing): Any portion of a roadway distinctly indicated for pedestrian crossing by lines or other markings on the surface.

Crowding: It is more than the objective density of users in a particular area, it is a subjective judgment on the part of an individual that there are too many other people there.

Crown (Crowning): A method of trail construction where the center portion of the tread is raised to allow water to disperse to either side of the trail.

Crown: The branches, twigs, and leaves of a tree.

Crown Cover: The degree to which the crowns of trees are nearing general contact with one another.

Crusher Fines (Crusher Run, Crushed Stone, Limestone Fines, Crushed Granite, Inch-to-Dust): Limestone, granite, or gravel that has been run through a crusher producing fragments ranging in size from dust to a specified size. Once wetted and compacted crusher fines create a smooth hard trail surface for high-use areas or accessible trails.

Cryptosporidiosis: A disease of the intestinal tract caused by the parasite Cryptosporidium parvum occurring in untreated backcountry water sources. Common symptoms include stomach cramps and diarrhea.

Cultural Resource(s): The physical remains of human activity (such as artifacts, ruins, burial mounds, petroglyphs, etc.) having scientific, prehistoric, or social values.

Culvert, Cross Drainage: Pipe- or box-like construction of native rock, wood, metal, plastic, or concrete under a trail to catch surface water from side ditches and direct it away from a trail. Generally, a catch basin is created above the trail; the culvert is then buried underneath the trail between the catch basin and the downhill side. Sometimes a rock lining is laid on the downhill side to slow the flow of water.

Culvert, Stream Bed: Pipe- or box-like construction of wood, metal, plastic, or concrete that conveys a stream under a trail without constricting waterflow.

Cumulative Impact: The impact on the environment which results from the incremental impact of the action when added to other past, present, and reasonably foreseeable future actions regardless of what agency or person undertakes such other actions. Cumulative impacts can result from individually minor but collectively significant actions taking place over a period of time.

Cupped (Cupping): A board or plank whose edges are higher or lower than the center. Cupping is often found in decks, where the board edges are higher than the middle. Water, trapped in the cupped area, accelerates rot. Cupping also refers to a process of erosion that turns the trail into a gully or the opposite of crowning. Lowering of the center portion of the tread due to user caused erosion or stock traffic, loosening soil in the center of the tread which is then removed by water or kicked off and built up into a berm.

Curb: A wood, concrete, or stone component (2 to 8 inches high) built along the edge of a trail or street to form part of a gutter.

Curb Cut: A cut in the curb where a trail crosses a street. The curb cut should be the same width as the trail.

Curvilinear: A free-flowing trail layout pattern characterized by the general absence of straight trail segments allowing for ease of trail user movement.

Cushion Material: Native or imported material, generally placed over rocky sections of unsurfaced trail to provide a usable and maintained travelway.

Customer: The user, consumer, patron, guest, stakeholder, or visitor who consumes a product, resource, or service provided "free," at some level of fee or user charge below the true cost, or at full cost from a park and recreation agency or private concessionaire operating under the control of the park and recreation agency.

Cut and Fill: The process of removing soil from one area and placing it elsewhere to form a base for any given activity.

Cut Bank: The outside bank of a bend, often eroding opposite a point bar.

Cut Off: A channel cut across the neck of a bend.

Cut Slope: An earthen slope that is cut. For example, a trail built lower than the existing terrain would result in a cut slope.

Danger: A built or natural feature likely to cause harm or result in injury.

Dab: To put a foot on the ground when riding a motorcycle or mountain bike to prevent yourself from falling over.

Dam: A barrier constructed across a waterway to control the flow or raise the level of water. The embankment can be used as a trail to cross a river.

Dam, Check: An earthen, stone, or log, dam placed across deeply eroded trails or erosion channels to slow the flow of water enough to allow accumulation of fine fill material behind the structure. Recommended primarily for use in trail reclamation or revegetation.

Dap: A shallow hole or slot drilled or routed in a piece of wood allowing a space to fit over a piece of hardware (a nut, the head of a bolt, or a portion of a steel plate or angle) that is connected to an adjacent piece of wood.

Davis-Bacon Act: The Federal law (enacted in 1931) that requires the local prevailing wage to be paid to all laborers or mechanics employed on direct federal contracts in excess of $2,000.

Day Pack: A soft pack (smaller than a backpack), favored by day hikers and trail workers for carrying food, water, and other supplies.

Daylight Edge: The outer edge of a trail. The point where the trailway and the cross slope meet.

Daylighting: Clearing a ditch, drain, or culvert so that water can run freely, or all the way to "daylight."

Deadfall: A tangled mass of fallen trees or branches.

Deadman/Deadmen: A log or logs, heavy timber or timbers, a large block of concrete, a large rock or boulder, or combination of these materials that is partially or completely buried in the ground or a stream bank. Deadman are used to anchor sections of armored trail, retaining wall, or the end of a winch or come-along chain or cable. Eyebolts placed in deadmen are used to tie in revetment with cable or chain. Log or timber deadmen (without eyebolts) are used in log or timber retaining walls. They are placed perpendicular to the face of the wall, extending into the earth behind it to prevent the wall from falling over.

Debarking: Stripping bark from logs with a sharp bladed tool such as a drawknife.

Deberming: Removing the high ridge of material that has formed along the outer (downhill) edge of a trail, allowing water to once again flow off and not down the trail.

Debris: Any undesirable material that encroaches on a trail and hinders the intended use.

Debris Flow: A rapidly moving mass of rock fragments, soil, and mud, with more than half of the particles being larger than sand size.

Debris Torrent: Rapid movement of a large quantity of materials (wood and sediment) down a stream channel during storms or floods. This generally occurs in smaller streams and results in scouring of the streambed.

Decibel (dB): The unit used to express the sound pressure level. Decibels are measured in several scales. The "A" weighting scale, expressed as dB(A), approximates human hearing and is used for the Standard Stationary motorcycle and ATV sound test procedures.

Decibel Level: A level of sound, usually referred to in governmental ordinances.

Deciduous: Trees and plants that shed their leaves at the end of a growing season.

Decking (Plank Decking, Flooring): The portion of a bridge, puncheon, corduroy, or boardwalk structure that provides direct support for trail traffic.

Declination: The measurement describing the difference between true north and magnetic north.

Dedication: The setting apart by the owner and acceptance by the public of property for public use, in accordance with statute or common law.

Decomposer: Any of various organisms (as many bacteria and fungi) that feed on a break down organic substances (such as dead plants and animals).

Decomposition: The breakdown of matter by bacteria and fungi, changing the chemical makeup and physical appearance of materials.

Deed: A legal document that transfers a property.

DEET: The active ingredient (chemical name N, N-diethyl-meta-toluamide) used in many insect repellents to repel biting pests such as mosquitoes and ticks.

Deflector: A device intended to turn aside the flow of water.

Degradation (Degrade): Progressive lowering of a channel bed due to scour. Opposite of aggradation.

Dehydration: A depletion of body fluids that can hinder the body's ability to regulate its own temperature.

Delta: The fan-shaped area at the mouth, or lower end, or a river, formed by eroded material that has been carried downstream and dropped in quantities that can not be carried off by tides or currents.

Demand: The quantity of trails and greenways or activity desired. The demand (number of visitors in relation to price) for goods or services that cannot be met because of a lack of market capacity to respond to the demand. Demand for trails and greenways that cannot be satisfied with the existing facilities. A demand approach can be used to estimate the existing and future recreation use of an area.

Demand Analysis: A study of the factors that affect demand, performed by collecting data and using various analytical techniques to understand demand.

Demographic: Related to the vital statistics of human populations (size, density, growth, distribution, etc.) and the effect of these on social and economic conditions.

Descent: A downward incline or passage or process of descending from a higher to a lower location.

Descent, First: A much-coveted prize; first to descend a certain river or route.

Designated on the Ground: The location of materials, work areas, and construction items, including lines and grades, marked on the ground with stakes, flagging, or paint.

Designated Route (Roads and Trails): Specific roads and trails identified by the agencies where some type of use (motorized or nonmotorized) is appropriate and allowed either seasonally or yearlong and which have been inventoried and mapped and are appropriately signed on the ground.

Desired Future Condition (DFC): A portrayal of the land or resource condition which are expected to result if goals and objectives of an agency plan are fully achieved. This description is written in terms of physical and biological processes, the environmental setting, and the human experience.

Difficulty Levels (Ratings): A subjective rating of degree of challenge a trail presents based on an average user with average physical abilities and skills. Difficulty is a function of trail condition and route location factors such as alignment, steepness of grades, gain and loss of elevation, and amount and kind of natural barriers that must be crossed. Snow, ice, rain, and other weather conditions may increase the level of difficulty. For example, some trail providers use Easy, Moderate, Difficult. Many other agencies use the USDA Forest Service levels:

• Easiest: A trail requiring limited skill with little challenge to travel
• More Difficult: A trail requiring some skill and challenge to travel.
• Most Difficult: A trail requiring a high degree of skill and challenge to travel.

Digging-Tamping Bar: A long bar with a small blade at one end for loosening compacted or rocky soil and a flattened end for tamping.

Dike (Raised Causeway): A low wall, often of sod, dividing or enclosing lands. The embankment is often used as a trail.

Dip (Grade Dip, Grade Brake, Drainage Dip, Drain Dip, Reinforced Drainage Dip, Rolling Dip, Rolling Grade Dip, Coweta Dip, Grade Reversal, Spoon Dip, Paved Dip, Armored Dip, Reinforced Dip): A reverse or gradual dip in the grade of the trail, 20 to 40 feet long, followed by a gradual rise of 2 to 3 feet with the rise at an angle to the outslope to divert water off the trail. This accomplishes the same effect as a waterbar, but will last longer due to the gentle dip and rise of the trail grade. A paved or armored dip is a drainage structure paved with stones to enable water to run across a trail without erosion. A reinforced dip is a drainage structure that has a waterbar buried under a layer of compacted soil. These structures are best when designed in during initial construction, but can be added later.

Dirt Bike: Off-highway motorcycle, trail motorcycle.

Discharge: The volume of water passing through a channel during a given time, usually measured in cubic feet per second.

Distance Zones: A subdivision of the landscape as viewed from an observer position. The subdivision (zones) includes foreground-middleground, background, and seldom seen.

Disturbance: Any management activity that has the potential to accelerate erosion or mass movement. Also, any other activity that may tend to disrupt the normal movement or habits of a particular wildlife or plant species.

Disturbed Area: Area where vegetation or topsoil has been removed, or where topsoil, spoil, or waste has been placed.

Ditch: A long, narrow trench or furrow dug improve drainage.

Ditch, Collector (Collection, Sidehill, Parallel): A drainage structure that runs parallel to the trail and intercepts water flowing/seeping toward a trail and channels it underneath the trail through a culvert or across in a drainage ditch which allows the water to cross the trail.

Ditching, Sidehill: A ditch which parallels the treadway on the uphill side to collect water seeping into the trail, usually ends in a drainage ditch which allows the water to cross the trail.

Dodgeway: A V-shaped stile through fences, used to allow hikers to pass through livestock enclosures.

Down and Out: The correct position of a carabiner gate when it is connected to an anchor.

Down Tree: Fallen tree that blocks the trail.

Downslope: The downhill side of a trail.

Drain, Cobble: A cobbled improvement to the trail surface that allows drainage (usually from an intermittent wet seep) across the trail for continued passage along the trail without damage to the soil.

Drain, French: A stone-filled ditch that can have a porous pipe laid along the base to collect the water and carry it away from the site. The top must be kept clear of the surfacing material; allowing water to run freely into the drain.

Drainage: The way in which water flows downhill and/or off the trail.

Drainage, Cross: Running water in swamps, springs, creeks, drainages, or draws that the trail must cross.

Drainage, Sheet: Desirable condition in which water flows in smooth sheets rather than rivulets; slower flow and less concentration results in less erosion.

Drainage, Surface: Rain or snow runoff from the surface of the tread.

Drainage Ditch (Ditching): Open ditches running parallel to the trail tread that collect water and carry it away from the site. A drainage ditch is also an element of a waterbar, providing an escape route for water diverted from the trail by the bar.

Drainage Structure: A water diversion structure constructed across the trail tread to remove water flowing down the trail tread or to prevent it from entering the tread.

Draw: Small valley or gap.

Drawings: Documents showing details for construction of a trail or trail-related facility, including but not limited to straight-line diagrams, trail logs, standard drawings, construction logs, plan and profile sheets, cross-sections, diagrams, layouts, schematics, descriptive literature, and similar materials.

Drawknife: A tool with a sharp blade and handles at both ends used to strip bark from small-diameter logs.

Dress: To chip or shape a rock finely to fit into a space in a structure.

Drift: Material of any sort deposited by geological processes in one place after having been removed from another. Glacial drift includes the materials deposited by glaciers and by the stream and lakes associated with them.

Driftpin: A 12- to 30-inch steel bar or pipe used to keep logs and timbers in place.

Drop-off: Slope that falls away steeply.

Drought: A period of dryness, especially a long one. Usually considered to be any period of soil moisture deficiency within the plant root zone. A period of dryness of sufficient length to deplete soil moisture to the extent that plant growth is seriously retarded.

Dry Wash (Sandwash): A streambed that carries water only during and immediately following rainstorms.

Dual-Sport Event: A motorcycle event in which vehicles must be licensed for street use and have a off-highway vehicle tag. These events are low-speed, non-competitive, touring events on paved and non-paved roads and trails.

Due Diligence: Refers to whether or not land management agencies are identifying and addressing problems. If a problem has been identified and has some plan for dealing with it, that offers some level of liability protection until the hazard has been dealt with.

Duff (Leaf Litter, Organic Matter): Any combination of loose vegetation, vegetable matter, roots, and/or organic laden soil produced by cutting trail. Duff retains moisture and rots away quickly if not removed from trails. This results in the formation of depressions and pockets, which retain water and cause erosion problems.

Dunes: Ridges or mounds of loose, wind-blown material, usually sand.

Duty of Care: The legal "duty of care" that a landowner owes a member of the general public varies from state to state, but generally liability depends on the status of the injured person. Liability increases from the lowest risk for a "trespasser," then "licensee," "invitee," with highest owed to a "child."

Dynamite: Blasting explosive based on nitroglycerin but much safer to handle than nitroglycerin alone, patented in 1867 by the Swedish physicist Alfred Nobel.

Earplugs: Small foam ear inserts used to reduce loud noise.

Easement: Grants the right to use a specific portion of land for a specific purpose or purposes. Easements may be limited to a specific period of time or may be granted in perpetuity; or the termination of the easement may be predicated upon the occurrence of a specific event. An easement agreement survives transfer of landownership and is generally binding upon future owners until it expires on its own terms.

Easement, Conservation: Places permanent restrictions on property in order to protect natural resources.

Easement, Construction: An additional temporary area or corridor needed to construct a trail or facility.

Easement, Maintenance: An additional permanent area or corridor (not open to the public) needed to maintain trail drainage, foliage, and recurring maintenance needs.

Easement, Recreation: Provides public access to private property while limiting or indemnifying the owner's public liability.

Easement, Scenic: Places permanent restrictions on a property in order to protect the natural view.

Ecological Corridor(s): Purchased/protected primarily for natural resource protection or wildlife corridors, although they often contain trails or other amenities aimed at serving the human population.

Ecology: The branch of biology that deals with the mutual relations among organisms and between organisms and their environment.

Economic Impact (Benefit, Value): The extent to which a given one-time economic event or ongoing economic activity contributes to the economy of a region. Economic impacts from trails can include: the building of new trails (one-time economic event), spending directly associated with trail users (ongoing economic activity), and additional spending induced by spending from trail users (indirect economic impact).

Economic Demand: The consumer's willingness and ability to purchase some quantity of a commodity based on the price of that commodity.

Ecosystem: A system formed by the interaction of living organisms, including people, with their environment. An ecosystem can be of any size, such as a log, pond, field, forest, or the earth's biosphere.

Ecosystem Concept: Brings biological, physical, social, and political worlds together into a holistic framework within which all systems can be described, studied, and managed.

Ecosystem Management: A strategy or plan to manage ecosystems to provide for all associated organisms, as opposed to a strategy or plan for managing individual species.

Eco-Tourism (Eco-recreation, Nature-Based Tourism): Purposeful travel to natural areas to understand the culture and natural history of the environment, taking care not to alter the integrity of the ecosystem, while producing economic opportunities that make the conservation of natural resources beneficial to local people.

Eddy: A current running contrary to the main current, causing water turbulence, e.g., below the bridge pier where swift current is passing through, or below a bar or point.

Effects (or Impacts): The biological, physical, social, or economic consequences resulting from a proposed action. Effects may be adverse (detrimental) or beneficial, and cumulative, direct, or indirect.

Effects, Cumulative: The impact on the environment which results from the incremental impact of the action when added to other past, present, or reasonably foreseeable future actions. Cumulative impacts can also result from individually minor but collectively significant actions taking place over a period of time.

Effects, Direct: Effects on the environment which occur at the same time and place as the initial cause or action.

Effects, Indirect: Effects also caused by the action, but occurring at a later time or further removed in distance.

Effluent: Something that flows out or forth, especially a stream flowing out of a body of water.

Egress: A right to go upon the land of another.

Elevation: The height of a place (mountain or other landmark) given in the number of feet or meters above sea level.

Elliptical Triangle (Pregnant Triangle): Shape of signs and blazes that mark trails in the National Trails System.

Embankment: An artificial deposit of material that is raised above the natural surface of the land and used to contain, divert, or store water, support roads, railways, trails, or for other similar purposes.

Eminent Domain: The authority of a government to take (usually upon payment of just compensation) private property for public use.

Encroachment: Unauthorized use of trail or greenway right-of-way or easements as for signs, fences, buildings, etc.

End-to-Ender: A person who has traveled the entire distance between termini of a long distance trail.

Endo: To crash by going over the motorcycle or mountain bike's handlebar. Short for "end over end."

Enduro: Endurance motorcycle racing, usually along a marked course full of challenges such as steep hills, banks, and ramps, etc.

Enhancement Funds (Transportation Enhancements): Under TEA-21, independent funds available for bicycling and walking facilities, rail-trails, and eleven other activities.

Environment: The aggregate of external conditions (physical, biological, economic, and social) that may act upon an organism to influence its development. Environment, Natural: Those parts of the landscape with features more closely resembling what they otherwise would presumably be like if they were left undisturbed by human activities. Environmental Analysis: An analysis of alternative actions and their predictable short-term and long-term environmental effects, incorporating physical, biological, economic, and social considerations. Environmental Assessment (EA): A document which complies with NEPA law and regulation prepared early in a planning process (federal) that evaluates the potential environmental consequences of a project or activity. An assessment includes the same topical areas as an EIS, but only assesses the effects of a preferred action, and in less detail than an EIS. An EA results in a decision, based on an assessment of the degree of impact of an action, that an EIS is necessary, or that an action will have no significant effect and a finding of no significant impact (FONSI) can be made.

Endangered species: Any plant or animal species that is in danger of extinction throughout all or a significant portion of its range, and has been officially listed as endangered by the Secretary of Interior or Commerce under the provisions of the Endangered Species Act. A final rule for the listing has been published in the Federal Register.

Enduro: Endurance motorcycle racing, usually along a marked course full of challenges such as steep hills, banks, and ramps, etc.

Enhancement Funds: Under TEA-21 and successor federal legislation, independent funds available for bicycling and walking facilities, rail-trails, and eleven other activities.

Environment: The aggregate of external conditions (physical, biological, economic, and social) that may act upon an organism to influence its development.

Environment, Natural: Those parts of the landscape with features more closely resembling what they otherwise would presumably be like if they were left undisturbed by human activities.

Environmental Assessment (EA): A document which complies with NEPA law and regulation prepared early in a planning process (federal) that evaluates the potential environmental consequences of a project or activity. An assessment includes the same topical areas as an EIS, but only assesses the effects of a preferred action, and in less detail than an EIS. An EA results in a decision, based on an assessment of the degree of impact of an action, that an EIS is necessary, or that an action will have no significant effect and a finding of no significant impact (FONSI) can be made.

Environmental Clearance: The status of a project that has conformed to the National Environmental Policy Act (NEPA), and other relevant Federal and State environmental laws.

Environmental Education: Activities that use a structured process to build knowledge, in students and others, about environmental topics.

Environmental Impact: The positive or negative effect of any action upon a given area or source.

Environmental Impact Statement(s) (EIS): A full disclosure, detailed federal report which, pursuant to NEPA law and regulation, establishes the need for the proposed action, identifies alternatives with the potential to meet the identified need, analyzes the anticipated environmental consequences of identified alternatives, and discusses how adverse effects may be mitigated. An EIS is prepared in two stages: a draft (DEIS) statement which is made available to the public for review and a final (FEIS) statement which is revised on the basis of comments made on the draft statement.

Equestrian: Of horses, horseback riding, riders, and horsemanship.

Equine Liability Statute: Many states have a statute which recognizes that any and all activities involving horses are inherently dangerous.

Erosion: Natural processes (water, wind, ice, or other physical processes) by which soil particles are detached from the ground surface and moved downslope, principally by the actions of running water (gully, rill, or sheet erosion). The combination of water falling on the trail, running down the trail, and freezing and thawing, and the wear and tear from traffic create significant erosion problems on trails.

Erosion, Accelerated: Soil loss above natural levels resulting from human activities.

Erosion, Gully (Gullying): Where concentrations of runoff water cut into the soil forming single or numerous channels greater than one foot below post-construction tread depth usually on steep terrain.

Erosion, Rill: Removal of soil particles from a bank slope or trail tread by surface runoff moving through relatively small channels.

Erosion, Sheet: The removal of a fairly uniform layer of soil material from the land surface by the action of rainfall and runoff water.

Erosion, Splash: The spattering of small soil particles caused by the impact of raindrops on wet soils. The loosened and spattered particles may or may not be subsequently removed by surface runoff.

Erosion, Streambank/Channel: The removal, transport, deposition, recutting, and bedload movement of material by concentrated flows.

Erosion, Wind: Removal of soil particles by wind, causing dryness and deterioration of soil structure; occurs most frequently in flat, dry areas covered by sand or loamy soils.

Erosion Control: Techniques intended to reduce and mitigate soil movement from water, wind, and trail user traffic.

Escarpment: A steep slope or cliff formed by the erosion of the inclined strata of hard rocks.

Eskimo Roll: A complete rollover in kayaking, from upright to upside-down to upright.

Estuary: A partially enclosed body of water freely connected to the ocean, within which the seawater is diluted by mixing with freshwater and where tidal fluctuations affect river water levels. The estuary is a dynamic system typified by brackish water, variable and often high nutrient levels and by shallow water conditions often associated with marsh plants in upper tidal zones and eelgrass in lower tidal zones.

Evaporation: The physical process by which a liquid (or a solid) is transformed to the gaseous state. In hydrology, evaporation is vaporization that takes place at a temperature below the boiling point.

Evaporative Heat Loss: When you sweat, you lose heat through the evaporation of the liquid. This is great in warm weather because it cools the body; but when it is cold and once you stop moving, your clothes remain wet, which can lead to chilling.

Event: A single, structured, organized, consolidated, or scheduled meeting or occurrence for the purpose of recreational use. An event may be composed of several related activities.

Excess Excavation: Material in the trailway in excess of that needed for construction of the designated trail.

Exclosure: An area fenced to exclude grazing animals and/or OHVs, usually for protection and study purposes.

Exotic Species: A plant introduced from another country or geographic region outside its natural range.

Expert Witness: A witness is a person who testifies as to what they have observed by sight, sound, etc. An expert witness may testify additionally as to matters of opinion on subjects within fields for which they are qualified.

Exposure: The relative hazards encountered when one takes into consid