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

Back-cut - The vertical part of the bench cut that’s blended into the
backslope.

Backslope - Slope on the uphill side of the trail. This should be a gradual
change from the tread, slowing runoff by preventing a waterfall effect.

Bench cut - A semi-flat trail tread created by digging down to mineral soil
in the hillside. Care must be taken to preserve some outslope while making
a ridable and walkable path.

Berm - The ridge that develops along the downhill edge of a trail. It’s caused
by tread compaction and soil displacement during trail use. A berm traps
water on the trail.

Bridges - Allows trail users to pass over ravines, bogs, creeks, rivers and
similar obstacles.

Climbing turn - A turn that transitions from one leg to the next as the trail
ascends (or descends) a hill.

Clinometer - Instrument used to measure the slope of ground. Also known
as an inclinometer or clino.

Contour trail – Pathway that gently traverses a hill or sideslope, following
natural contour lines as illustrated by a topo map. Allows water to sheet
across the trail, thus minimizing impact to the tread.

Control points - Places of interest that trail users will be attracted to
(desirable) or should avoid (inappropriate). Mark control points and use
them to determine the placement of a new trail.

CORA - Cincinnati Off Road Alliance. Mountain Bike Group formed in 1994 in Greater Cincinnati Area.

Crib wall - A retaining wall that raises the trail significantly. Often used to
stabilize the trail tread and prevent it from collapsing down the fall line. Can
be built with rock or wood.

De-berming - Removing the berm, or ridge of dirt that forms along a trail’s
downhill edge. Restores the tread’s outslope, allowing water to sheet off.
(See "outslope" and "berm.")

Directional use trail - A trail intended for travel in one direction only. May
be reversed periodically.

Drainage – Removal of water from the trail.

Erosion – The natural process of wearing down and moving rock and soil by
wind and water. Trail erosion can be accelerated by a combination of users,
water and gravity.

Fall line - Direction that water flows down a hill. The path of least resistance.

Fillslope - The portion of a trail that’s constructed from excavated material.
Fillslope can be unstable so should not be used to build trail tread. Full
bench construction is preferred.

Flow – The rhythm or "feel" of a trail. Two basic types include "open and
flowing" and "tight and technical."

Full bench tread construction – Tread construction method of excavating
down and into the hillside. Puts the entire tread width on mineral soil, maximizing
sustainability. (See "bench cut.")

Grade – Trail steepness. (See "percent of grade.")

Grade reversal – Brief change in trail grade direction, such as routing a
downhill section back up the hillside for a short distance. Used to divert
water off the trail.

Grade dip – Undulation in the tread that traps water and diverts it off the
trail. Makes trails more interesting and fun to use.

Half rule or 50 percent rule - If the trail grade exceeds 50 percent of the
hillside slope, gravity will pull water down the trail instead of across it. This
is known as "exceeding the fall of the hill."

Hybrid – A trail design that blends "open and flowing" and "tight and
technical" features.

IMBA - International Mountain Bicycling Association, P.O. Box 7578,
Boulder, CO, USA 80306; (303) 545-9011; www.imba.com. Leading
resource for mountain bike-oriented trail design, construction, maintenance
and management information, and mountain biking in general.

Knick – Shaved-down section of trail, about 10 feet in diameter, with an
exaggerated outslope. Like a rolling grade dip, a knick is used to shed water
off a trail.

Land manager - Any person responsible for decisions regarding the use of
public or private lands.

Mineral soil - Dirt that’s below the top layer of leaves, roots and other
organic material. When making a bench cut, always dig down to mineral soil
if possible.

Multiple-use trails - Those used for more than one type of activity, such as
for cycling, hiking and horseback riding.

Open and flowing - A trail design marked by sweeping turns, higher speeds
and longer sight lines.

Outslope – Trail tread that’s canted very slightly in the same direction as the
hill’s slope. Allows water to sheet across rather than be trapped.

Percent of grade – Preferred method of measuring slope or a hill’s
steepness. For example, a grade of 10 percent means there is a rise or fall
of 10 vertical feet per 100 linear feet.

Re-route – A new section of trail that replaces an existing section. Rerouting
is often the best remedy for a poorly designed trail that requires
frequent maintenance.

Rolling grade dip - A non-obtrusive feature that diverts water off the trail
by altering the grade. It’s essentially a man-made grade reversal.

Sheet flow - A dispersed flow of water. It minimizes erosion by preventing
water from achieving high velocity and carrying away topsoil.

Sill - Stone or timber supports that keep bridge stringers from contacting the
ground.

Singletrack - A trail so narrow that users must generally travel in single file.

Single-use trails - Designed for only one type of user. This can be a problem
if other users begin traveling the trail.

Slope - The natural (or man-made) pitch of the land, as shown on
contour maps. Generally refers to the hill, not the trail. The trail "slope"
is called "grade."

Social trails - Paths created by people who wander away from set trails.

Stringer - A structural component of a bridge. It spans from bank to bank
and supports the decking.

Sustainable trails – What every designer and construction crew should strive
for: low-maintenance trails that have minimal impact on natural systems.

Switchback – A sustainable turn on a hillside. The trail is routed onto a level
deck where it makes a transition to the opposite direction.

Texturing - Placing natural features (rocks, logs, etc.) back into the tread
to increase its technical nature. Helps limit speed, and thereby reduces
user conflict.

Tight and technical - A trail design that includes tight turns, natural
technical features and mandates slower speed.

Topographic map or "topo" map - Charts elevation changes and shows
features such as knolls, ravines, rivers and contours.

Trail corridor - The area around and above the tread. Remove fast-growing
impediments, but leave grasses and trees.

Tread - Ground on which trail users travel. It may include grass, bare dirt,
roots or rocks. Tread width varies depending on the type of trail and its users.

Tread creep - Describes a contour trail sagging or sliding down the hill.
Causes include bushes or trees protruding into the trail from above, exposure
of roots from an uphill tree, an improper bench cut or poor trail flow.

Turnpike – Trailbuilding technique that uses a combination of gravel, soil or
other filler material to make the tread higher than the surrounding water
table. Useful in low-lying areas with poor drainage.