Hiking trails don't grow on trees -- as do the leafy green canopies that drew more than 276 million visitors into the U.S. National Park system in 2004. Faced with a $5 billion maintenance backlog and annual attendance nearing the total U.S. population, our parks need help from those of us who take advantage of their pristine wilds at no cost.

"All over the country, many trails are impassable right now, because agencies don't have funding to maintain them," says Shirley Hearn, volunteer programs manager of the Washington, D.C.¿based American Hiking Society (AHS). "If funding continues to dwindle, the only way trail work will get done is through volunteers."

In light of this crisis threatening one of our finest national resources, why not use your next getaway to lend a hand? Thousands of short-term and long-term positions are available in national and state parks across the U.S., on both a volunteer and paid basis. Hearn's program, Volunteer Vacations (tel. 800/972-8608, x206;, rallies backpackers, birdwatchers, and Dharma bums to donate a week or two of their time to help clear paths, correct erosion, build bridges in boggy areas, and perform other general maintenance tasks. For $120 ($95 for AHS members), the program takes volunteers through stunning scenery while they pitch in with upkeep along the way.

And what's a little work, when your job is to weed rainforest flora while hiking ten miles a day through Maui's incomparably beautiful Haleakala National Park? For some, such experiences become an addictive avocation: Joe Burton, a retired engineer from Ohio, volunteered for the first time in 1997 with no hiking experience. After backpacking nine miles into an Arizona canyon, he was so exhausted Hearn thought he'd never come back. He surprised her, though, and made eighty more trips since. "I came to feel I had no right to set foot on a trail someone had struggled to build unless I gave back," he says.

In 2004, Volunteer Vacations enlisted 675 people, who chose their own trips from among projects in thirty states. Assignments may be easy or strenuous. Most call for day packing into front country, but some require days of backpacking up to ten miles daily into remote base camps. Projects run from January through November, but they're designated on a first-come, first-serve basis. Hearn recommends applying early if you want your first choice of assignments. Registration forms are available on the AHS Web site.

AHS pays for all food, supervision, training, and tools for the job. Volunteers pay for transportation to the site and supply their own sleeping bags, tents, packs, and other gear. Anyone under 18 must be accompanied by an adult, but otherwise, all ages are eligible. "We have people in their eighties," Hearn says.

If you're under eighteen or can't afford to work without pay, consider a stint with the Student Conservation Association (tel. 603/543-1700; The SCA offers two types of programs: four-week, unpaid summer assignments for high school students; and long-term, paid internships, many of which can count toward academic credits, for anyone eighteen or older. SCA appointments include plum gigs such as the Biscayne National Park diving project, where students perform most of their work underwater, on reefs and shipwrecks; or the Lava Beds National Monument, in California, learning fire and fuels management skills; or tracking tortoise in the Mojave Desert.

The high school programs begin in mid June and run through early September. Students can specify the region where they'd like to work when they apply online, for a small application fee of $25. The process is competitive: 900 spots are available for up to 2,700 applicants, so SCA spokesperson Kevin Hamilton recommends applying as early as February.

Students are judged on the basis of their motivations as well as their experience and comfort-level in the outdoors. "You don't need experience building trails or shelters, but we want to know you won't mind sleeping outside with bugs," says SCA spokesperson Kevin Hamilton. Students pay for transportation to the job sites, but after that, SCA pays all expenses, including food, camping gear, cook stoves, and tools.

The adult internships range from 13 to 52 weeks in length. Applicants compete for nationwide assignments with agencies such as the National Park Service, the Forest Service, and the US Army Corp of Engineers. Those positions command stipends of $60 a week for 13-week programs, and $160 a week for programs that run six months or longer. SCA pays all expenses, including food and transportation to the job site.

The SCA's chief aim is to cultivate respect for the environment among young adults. Though they accept applicants of any age over 15, Hamilton says their primary demographic is 18 to 25-year-olds. Many alumni of the 48-year-old program now occupy key positions with leading conservation groups, such as Steve McCormick, CEO of the Nature Conservancy, and Bernie Zaleha, vice president of the Sierra Club.

Hamilton says, "We are responsible for the planet. It's up to us to bring along the next generation of environmental leaders."

"Volunteering makes you feel great -- to know you've done something that will be there for future generations. And it's a great way to see the country," adds Hearn.

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