Bryce Canyon is "a helluva place to lose a cow." It's also a helluva place to spot a cow. Though I saw Frisbee-size cow patties around my tent and cow-crossing signs posted in town, no cows grazed the land before me. But as a paying volunteer on a Sierra Club service trip--someone who was willingly sacrificing my vacation time, and money, to make a contribution to the Western environment--sighting animals was not the main objective. Building fences to confine them was. Wherever they might be.

On the "Bryce Canyon Through the Back Door" trip in southwest Utah, our mission was to construct barbed-wire fences that would keep the cows inside Dixie National Forest, where they are welcome, and out of Bryce Canyon National Park, where they are not. (The environmental benefits of this project, we eventually learned, are not as clear cut as we had hoped, of which more later.) Our back-country site was in the national forest, about 15 miles--or an hour-plus drive on rugged roads prone to miniature dust storms--from civilization.

The Sierra Club offers nearly 100 of these trips a year, in national wilderness areas across the United States, from Alaska to St. Croix to Maine. It is one of dozens of groups offering "service vacations" domestically and abroad. Projects range from general maintenance tasks (fixing trails with the American Hiking Society) to scientific research (collecting data on stomatopod crustaceans in Belize for the Oceanic Society). For the Sierra Club, volunteers in the Southwest have logged more than 100,000 hours while digging for Gallina artifacts, weeding noxious plants from Colorado river banks and extending the 750-mile Arizona Trail, among other things. The club's motto is: "To explore, enjoy and protect the wild places of the Earth." Erecting fences, presumably, falls under this rubric.

Days began at 7:30, with the clang of the breakfast bell stirring 29 volunteers from sleep. We shuffled into the commissary in ones, twos and threes: an Oregon college student, a college alumni magazine editor and a Medicare-age retiree, all traveling solo; an Iowa elementary school teacher and her boyfriend, a railroad worker who does John Wayne impressions; seven teenagers and the married founders/leaders of Chrysalis, a home-based program in Montana that uses challenging outdoor endeavors to help rehabilitate troubled adolescents after drug addiction, pregnancy or other hardships.

After frosted flakes or hash browns with Tabasco sauce, we would pack a lunch, fill bottles using the "water buffalo"--a giant metal receptacle that was our sole source of water and was refilled midweek by rangers--and convene at the bottom of the trail for the 12-minute hike to the job site.

Ah, the job site. The work, trip leader Susan Estes told us, would be arduous. In pre-trip literature, Susan suggested a thrice-weekly exercise routine to prepare participants for the altitude, hikes, heat and heavy loads. I quickly learned that regular workouts on the StairMaster get you, at most, to the visitors center of the 8,500-foot mountain. There is no modern workout to prepare you for hauling cedar posts; you can only grunt and bear it. Building a fence is more chain-gang labor than cooperative task. But it is a challenge nonetheless.

"If you can set a fence, ride a horse or milk a cow, you will never starve," offers Micheal "Cass" Castagnetto, the park's facility manager, who has been overseeing the Sierra Club project since it started seven years (and five miles of fence) ago.

Our group dispersed according to assignments, though each work station was flexible. I started the morning on a vertiginous slope with half a dozen others, including two of the garrulous yet hard-working teens and the 11-year-old daughter (the youngest volunteer) of the Chrysalis leader. Our job was to dig a hole for the cedar-and--metal posts, breaking through several feet of limestone and hardened red earth. We traded off jobs--operating an ear-crackling power drill and removing the chipped rock pieces on hands and knees. Every 300 yards, we'd plant another pole, under the direction of a park ranger and leader in training.

After an hour or so, a yelp for help elsewhere usually released me from my task. Up I hiked, until I reached a stack of logs. The job was to move the materials from Point A to Point B. A no-brainer. With assistant leader Dale Kemmerer, a semi-retired physician who could out-carry a Sherpa, I shouldered one end of the 60-plus-pound timber, feeling the bite of the bark through my T-shirt. We ran the materials back and forth, on countless trips, from the tool repository to the end of the line. Like members of a frenetic ant colony, we were always moving something. By day's end, I was removing fence erroneously placed 30 years ago. Wrapping a heavy chain around the rusted pole, I pumped the jack like I was changing a tire. The earth loosened, pushing forth the pole. One down, so many more to go.

Some tasks were fruitless, like spending a half-hour hunting for a tool along a poorly marked trail, only to be told it was not needed. Or I would be given a job but no tool. Occasionally the work became monotonous. But frequent water breaks, noon lunches beneath the pine canopy and spontaneous bursts of conversation and tomfoolery--water bottle fights, carving our initials in the cedar posts--lightened the workload. The highlight, oddly, was stringing the wire. From one end to another, between wooden frames called H-braces, we formed a barbed-wire-carrying conga line, threading the gnarled metal along the posts and securing it with clips and macaroni-shaped spacers. Messages were passed down the line: "Talk to me," "Pull up the slack," "Tighter," "ALL SET . . . All Set . . . all set." At 3:30, we called it a day. Leisure time.

An outsider might wonder what brought us here, to a dense Ponderosa forest, and why we chose to spend vacation time and a couple hundred dollars to perform hard labor for a herd of wayward (phantom!) cows. And what about the amenities, or lack thereof? The latrine was a knee-deep trench, a couple of logs, a white toilet seat, a bucket of lime powder and a panoramic view of the mountains. The shower: a tarp and a bag of sun-warmed water hung from a tree limb. The dining area: two cowboy cooks, a couple of picnic tables, three giant tubs of heated water. Accommodations were tents or the back seats of trucks.

"We are living in a remote location, with primitive conditions and doing manual labor," said Susan, who, when not volunteering, works construction in California. "Your friends will think you are crazy to pay for the privilege."

When asked on the first day why we came here and what we hoped to accomplish, most cited the need to give back to Mother Nature, to contribute more than cash, to partake in an adventure, to see the stars.

"I believe the Earth is a community, and one day it will ask me, 'What did you do to help?' and I don't want to say I just shoveled dirt in Louisiana," said Bob Kelso, a math professor at Louisiana State University and veteran Sierra Clubber.

For one New York investment banker, it was to heed the call of his conscience.

"On Wall Street, it was me, me, me or the client, client, client. I am a total city boy. I shower every day and am never 20 feet from a plumbing pipe. It was a self-centered existence," explained Rajesh Krishnan, who quit his job, dyed his hair green and signed up for three consecutive Sierra Club service trips. "But this gave me a chance to offset what humans degrade through their existence, to put things more in favor of the environment, to save Mother Earth."

Despite the altruistic goals, the barbed-wire project was a contentious issue. Most Sierra Club projects are cut-and-dried conservation: preventing erosion on an old Grand Canyon mining trail, tracking the mating calls of Southwest birds, stamping out invasive thistles. But barbed wire, also called "devil's rope," and the work of the Sierra Club sparked controversy. A waiter at nearby Ruby's Inn, at the foot of Bryce Canyon, advised against driving cars adorned with Sierra Club stickers. Monte Bowthorpe, the cowboy cook from Moab, Utah, said he almost declined when first asked to work for a Sierra Club outing.

The conflict prevails in Western lands protected by the government, mainly national parks and monuments, and spans decades. The struggle pits the ranchers, who wish to graze their cows unfettered, against the government, which hopes to maintain livestock-free zones for the million-plus annual tourists. Yet as more land is usurped for recreational use, more restrictions are placed on the ranchers, thus perpetuating a showdown of sorts. The locals tend to group environmentalists with government forces, viewing them as unwanted intruders. Erecting barbed wire also made many of us uncomfortable. The fence divides land that would otherwise be a natural whole. We also happened upon an animal's skeletal remains, raising the issue of whether our work was maiming or even killing the wildlife. Finally, I wondered where the cows were.

But after dining on elk and egg noodles, Cass and Susan reassured us that we were performing a good deed. That for the ranchers, the fence would save them from hefty fines and from chasing down bovines inside the park. That for the deer and elk, the fence would protect them from hunters, who cannot shoot on park property. (The animals seek out the fence, they told us. Deer jump over it, elk barrel through it and cows stand dumbly beside it.) That for environmentalists, it would protect the indigenous vegetation from "exotics" expelled by cows. And that for Sierra Club volunteers, our help, no matter how slight it seemed, would have an enormous payoff for future generations by preserving both traditional ranching and public uses of the land. It's the sum of the smallest parts--hauling logs, digging holes, rolling wire, clearing branches--that matters, he explained. And at last count, it added up to almost 900 yards of fence.

"You all got here," said Susan, when asked how she rates success. "Whatever else we can complete is sufficient, no matter how menial."

But Bryce Canyon, and the Sierra Club, for that matter, are not just about cows and fences and working the line. Exploring the environment is just as vital. Each person has one day off; I signed up for Wednesday. After breakfast, while half of the group headed to the site to help the chain-saw-wielding rangers clear a new section, I trekked out to Calf Creek on a five-mile hike with imposing burnt red canyons and, around the last dusty bend, a 126-foot waterfall. Once dried from the desert heat, I stopped by Bryce Canyon to gawk at the hoodoos, the sky-high rock formations shaped like candle-wax drippings, and sneak a shower at Ruby's Inn.

Free time was also squeezed in between fencing and dinner and dinner and bedtime. The first stop after work was the kiddie-pool-size swimming hole, which was ice cold from the melted snow runoff. With only two showers permitted all week, I jumped in with enthusiasm--if for nothing more than to rinse off the caked dirt. Once cleansed, and then fed, I'd join other sunset romantics on the mountain edge to watch the sky turn from blinding blue to dusty rose to silver-flecked black.

Late at night we gathered around the fire, sitting on tree stumps, drinking herbal tea or Wild Turkey with a Gatorade chaser and spinning yarns with the resident cowboys. Monte described the mining accident that cost him three fingers. Calvin laughed about the apoplectic horse that bucked him to high heaven. They told of the hardships of rodeo riders and gossiped about Hollywood celebrities--such as the cast of "Thelma & Louise"--who hired them to cook for their film crews.

For our farewell night, we rode into town to hear performer Michael Martin Murphey. The concert was held in a rodeo corral. Murphey sang of ranching and working the land, of sons and sweethearts, of saving the West. Horses whinnied; cowboys shouted out requests from the backs of pickup trucks.

And there we sat, in the second-to-last row, the Sierra Club volunteers, immersed in the moment, with our backs to the cows.

Sierra Club lists its service trips, as well as its sportier outings, on its Web site ( and in a brochure available by mail (415-977-5522). Most of the volunteer trips cost $300 to $500, transportation not included. This year, on a handful of trips, the club charged volunteers 25 and younger only $195. There are also special-interest outings for seniors, singles, women, even vegetarians. Participants must be Sierra Club members, and if not, can pay the $75 membership fee with the deposit.

Andrea Sachs last wrote about South Carolina's Bee City for Travel.

At Your Service: Planning a Volunteer Vacation

Organizations from all over the map offer vacation service projects, well, all over the map. For a definitive source on the groups and their offerings, check out "Volunteer Vacations: Short-Term Adventures That Will Benefit You and Others," by Bill McMillon (Chicago Review Press), or VolunteerAmerica! at www, which also posts upcoming projects.

Some of the bigger names in volunteer-trip groups include: Earthwatch Institute, 617-926-8200, or; Global Volunteers, 1-800-487-1074 or 651-407-6100, or; Habitat for Humanity, 1-800-HABITAT, or; American Hiking Society, 301-565-6704, or; Oceanic Society Expeditions, 1-800-326-7491, or; Amizade Volunteer Programs, 1-888-973-4443, or; and Global Citizens Network, 1-800-644-9292 or 651-644-0960, or www Trips are also offered through government agencies, universities, state parks, museums and zoos.

Each organization has a distinct flavor, if not philosophy, and it is important to speak to a leader or past participant before committing. Some questions to ask include:

* What are the group's/leader's environmental views and project goals? The leader sets the tone of the trip. An extreme environmentalist will not tolerate any human impact. That could mean cleaning your bowl with a piece of bread and then eating it, or even rinsing it with water and swallowing it. Or storing your trash until you are out of the park. At the other end are the more laissez-faire leaders, who may not enforce recycling and allow volunteers to head for the nearest 7-Eleven for morning coffee.

The leader also sets the work pace. Some are laid-back, with a loose plan; others are as regimented as drill sergeants.

* What is the relationship between the organization and the park rangers? For some groups, the rangers are instrumental in organizing the project. If there is a good rapport, and the two have worked together in the past, then the week should run smoothly. However, past Sierra Club volunteers reported that some of their projects fell through, due to political conflicts, bad weather or unpreparedness, and they ended up standing around or performing slapdash jobs that had little environmental value.

* What are the accommodations and what should one pack? Accommodations run the gamut. Some are very rustic, almost survivalist. Ours was in the back country, but it was more like car camping. (We drove rather than hiked to our site.) And still others are on campgrounds with showers, laundry and RV-parked neighbors, or near commerce centers, so if a critter eats your toothpaste, it's no big deal.

The organization or leader often provides a cursory list of items to bring, but depending on your threshold for extreme temperatures, it's important to ask about the heat of the day and the chill of the night--and pack accordingly. Veteran volunteers also may have personal suggestions that go beyond the essentials, such as a spare head lamp and extra toilet paper.

--Andrea Sachs