Updated 10/18/95
Trail width varies with intensity and type of use. Short recreational or
interpretive trails to be used for small groups should be wider than lightly
used, longer trails. Trails should be at least 2 to 4 feet wide; however,
tread width cannot exceed 6 feet if the trail is to be eligible to receive
Stewardship Incentive Program (SIP)* funding. Widths of 6 to 8 feet are needed
for pleasure walking and in areas with steep dropoffs. Educational or interpretive
trails must be wide enough to accommodate small groups, especially at points
of interest.
Clearing width should be at least 4 feet along the trail or 2 feet wider than
the trail on either side of the actual walkway (Figure 5). Wind the trail
around large, existing trees within the trail's path rather than opting for
total removal, and prune those trees' lower branches back to the trunk.
Figure 5. Trail clearing guidelines: Prune trees and shrubs 1 to 2 feet back
from trail edge. Prune tree branches 8 to 12 feet above trail surface.
Clearing should be kept to a minimum. In cleared areas, cut all brushy vegetation flush with the ground. Clear all hazards adjacent to and above the trail. Strategically located fallen logs and large rocks can be left in place to discourage vehicular use and add to the natural variety of the trail. On trails that will be used by school groups, make small clearings (turnouts) adjacent to points of interest that will allow group instruction.
Clearing heights should be at least 7 feet for foot trails, 8 feet for biking
trails, and 10 feet for equestrian trails. Periodic maintenance and monitoring
at different seasons of the year will be needed to prune drooping and ice- or
fruit-laden branches.
The grade, or slope, of the trail is the single most important factor in design and layout. The trail grade influences the length of the trail, level of difficulty, and drainage and maintenance requirements. Avoid creating long, sustained grades that can be tiring and monotonous to users. Try to maintain gentle slopes of 10 percent or less (less than 1 foot of drop over a 10-foot stretch). Gently undulate the grade to provide natural drainage and variation. Where steep grades are unavoidable, construct waterbars to slow runoff flow and to avoid erosion (Figure 6).
Figure 6. Waterbars are effective in controlling water flow on trails. Place them on
long or steep grades to minimize erosion and the need for trail maintenance.
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| Construction Step | File Size (megabytes) |
|---|---|
| Measuring | 2.32 |
| Digging | 2.85 |
| Placing | 2.18 |
| Ditching | 2.79 |
| Staking | 5.31 |
A line of rocks can be used instead of the log to slow water flow. Bury two-thirds of each rock in the soil.
Periodic Maintenance. Natural processes are constantly shaping and altering the
forests, and trails are no exception. Periodic upkeep and repair of trails must
be scheduled at least annually. Some degree of mechanical or chemical control
of resprouting brush will be required. Likewise, wooden and rock structures may
need repair or replacement. Always build with weather- and rot-resistant
materials to extend the life of structures.
To reduce the need to maintain and replace signs, consider using numbered signs keyed to an accompanying interpretive brochure that can be updated inexpensively as forest conditions change (Figure 7).
Figure 7. An interpretive brochure is an inexpensive user's guide and can be
altered as audiences and conditions change.
Periodic maintenance helps you avoid major construction. Schedule your maintenance in relation to the amount and extent of use. You also should consider the safety or liability constraints of your users. Maintenance on disability-accessible trails should include controlling weeds, preventing excessive cracking, and protecting the surface against erosion.
Surfacing Materials. Materials used to cover high-traffic and sensitive areas may need to be replaced or replenished periodically. When choosing these materials, seek out local supplies of natural bark, mulch, wood chips, sand, and gravel, preferably those that can be found on the tract.
In wet areas with
seasonal or standing water, surfacing is generally not feasible. In these areas
use boardwalks, catwalks, decks, or log bridges (Figure 8) to provide access
and minimize disturbance. Always provide handrails in deep-water areas and
where boardwalk height is greater than 2 to 3 feet.
Figure 8. A simple bridge design.
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