Hardening Soggy Tread with
Puncheon or Bog Bridging
By Bob Proudman and Beth Critton
“Very few critters like to get their feet wet,” according the Forest Service’s Trail Construction and Maintenance Notebook.
This month we want to explore wet trail, and some structures that Appalachian Trail builders plan and install so hikers can avoid wet feet
. Yep, it’s as plain and simple as that!
Indeed, if the A.T. passes through a bog or swamp, hikers will broaden the trail to avoid mud and deepening puddles, widening the tread and damaging soils and plant life as they pick their way through the muck, sometimes over a widespread area.
All trail work depends on what water does at the site:
- Flowing water moves downhill on slopes and sidehills, causing sheet-erosion and forming into rivulets, gullies, brooks, and streams.
- Standing water puddles, ponds, or creates swamps and wetlands by not moving or draining at all, or moving very slowly across flat areas in valley crossings or along flat, mountaintop bogs.
In A.T. parlance, bog bridging is the same as “puncheon”—that unusual word meaning a split-log or heavy slab of timber. An alternative is to build raised treadway or “turnpike” using native soil material and occasionally geotextile cloth. However, we will leave that for a future article.
Above, basic puncheon (A.T. Design, Construction, and Maintenance, 2nd edition, 2000)
Log or lumber bog bridges averaging eight feet in length and placed end-to-end can make even the soggiest trail sections accessible and pleasant, as well as protecting wetlands. They are often the best management practice in wet valley crossings or mountaintop bogs. And, they are interesting and fun to use, clomping along above the water and mud. As a hike leader, Beth enjoyed scheduling mid-day breaks as “luncheon on a puncheon!”
Occasionally, when a new beaver colony takes up residence, bog bridging may be essential to continue using a trail segment inundated by our furry, pond-loving friends. Once, when beaver-flooded waters became seasonally deeper, Bob had to cable a dozen puncheons together in a daisy-chain, using steel cables to prevent (or at least restrain) the bridges from floating away.
Several techniques are used. Native log puncheon may be harvested from available, rot-resistant trees near the site (agency policies allowing). They are topped and spiked to sill- or base-logs and placed end-to-end, sometimes numbering dozens in succession. Be sure to know your trees and choose appropriately before committing.
In the 1970s, Bob’s Appalachian Mountain Club (AMC) Trail Crew in the White Mountains used spruce and fir trees, the only available species along high mountain bogs there, and even pounded in a “Golden Spike” to commemorate completing its first traverse of dozens of miles of Mahoosuc bogs in 1976.
Harvesting locally had impacts and limitations, however. Today, much of AMC’s puncheon is made of rough-cut, rot-resistant, dimensional tamarack or larch on cedar base-logs airlifted into the site. While a topped, native fir bridge may last seven to ten years, a dimensional bridge on cedar-tamarack should last 20 to 25 years.
Which are ATC’s wettest regions, and which have the greatest amount of puncheon or bog bridging?
Mountain Club of Maryland puncheon project in Pennsylvania (Photo by Thurston Griggs)
Except for the Ceres-Nebo boardwalk in the Piedmont A.T. Hikers’ section in Virginia, all but about 300 feet of puncheon inventoried along the A.T. is found either in the Mid-Atlantic region or in New England, with the greatest total way up north. From New York to Katahdin, poorly drained soils predominate in those formerly glaciated regions, where peat bogs and mucks sit on top of glacially compressed “hardpans” that hold water in swamps and wetlands. Indeed, in the NPS Appalachian Trail asset inventory, puncheon now totals in the thousands
of linear feet, and increases annually, in the six northernmost states.
As always, we invite your questions and comments.
Beth Critton is Chair of the Stewardship Council
Bob Proudman is now an ATC consultant contributing to The Register.
Welcome Keystone Trails Association!
The Appalachian Trail Conservancy is pleased to welcome the Keystone Trails Association
(KTA) to an elite group—the 31 Appalachian Trail maintaining clubs!
KTA now has responsibility for the Pennsylvania A.T. section between Lehigh Furnace Gap and Little Gap that was previously maintained by the Philadelphia Trail Club, which found its priorities had changed over the years and voluntarily relinquished that Trail assignment.
KTA Secretary Jim Foster said in a recent KTA newsletter
, "In a sense, maintaining a section of the AT is a return to KTA’s roots. KTA was founded 60 years ago in part to supervise the maintenance of the AT in Pennsylvania. KTA volunteers have jumped right in and have been out working on the A.T., maintaining the A.T. corridor, and recruiting volunteers."
KTA, a volunteer-directed, public service organization is a federation of membership organizations and individuals dedicated to providing, preserving, protecting and promoting recreational hiking trails and hiking opportunities in Pennsylvania, and to representing and advocating the interests and concerns of the Pennsylvania hiking community.
Webinars for A.T. Club Leaders
: A.T. Club presidents and active A.T. volunteers are invited to attend an online meeting on July 13 at 12:00 p.m. with Appalachian National Scenic Trail Superintendent Wendy Janssen and ATC Executive Director Ron Tipton. The registration deadline is noon on Wednesday, July 6. RSVP today.
Biennial Task Force Webinar:
Club leaders should look for an email inviting them to participate in a webinar and provide feedback on recommended changes to the ATC Biennial model. The webinars are scheduled for Mon. July 25 and Thurs. July 28 at 6:15 p.m. each evenings. While clubs may have more than one member participate, only one person from each club may serve as its spokesperson.
Social Media Webinar:
ATC is hosting this one-hour webinar on August 4 at 6:30 p.m. to showcase the range of different social media platforms available that can be used in many beneficial ways by A.T. Clubs. Organized by ATC intern Natrieifia Miller, it will highlight club success stories, share insights into new platforms, and answer questions you might have about how social media can work best for you. Participants should RSVP
to participate in real-time or to receive the recording of this webinar. RSVPs are requested by Monday, August 1.
Be Tick Smart
Lyme disease and other serious or even fatal illnesses
can be carried by deer ticks, wood ticks, and Lone Star ticks found in various areas along the Trail. More than one infection can be transmitted in a single bite. Deer ticks and their tiny nymphs
are the primary carriers of Lyme disease.
Keeping plant growth cut back along the footpath will help reduce the likelihood of hikers picking up ticks while walking on the A.T. Be sure and protect yourself while working on the Trail:
- Use insect repellent that contains 20 to 30 percent DEET on exposed skin.
- Treat shoes and clothing with permethrin, which repels or kills on contact. Treated bug-net pants over shorts are effective and allow for ventilation on warm, humid days.
- Wear light-colored clothing, making it easier to spot ticks.
- Check for ticks daily. Remove any embedded ticks using tweezers or a tick key to lift under the mouth parts in a slow, steady pull.
- Once inside, put clothes in the dryer on high heat for 60 minutes to kill any remaining ticks.
Even if you are not aware of having been bitten, be aware of symptoms of tick-borne illness
and seek medical attention. Early symptoms usually occur within in one to three weeks of a bite and include:
- muscle/body aches