In a twin-engine airplane bumping and skidding at 220 miles an hour through choppy mountain skies, Reid Jackson of the United States Forest Service is showing off his forest.

The GS-14 bureaucrat who runs the largest national forest in the continental United States cannot contain his pride. With childlike exuberance, Jackson's eyes flit from a crumpled map in his hands to the seemingly endless wilderness below.

Black granite mountains, their ragged peaks rising more than 13,000 feet, jut through great fields of ice. The pristine waters of nearly 1,500 alpine lakes show signs of the spring thaw. Down in the meadow, where 150 years ago mountain men met to trade beaver pelts and drink whiskey, aspen and willow trees are lime green with new leaves. And unseen from the air, the largest herds of elk and moose in North America wander through a forest more than half the size of the state of Maryland.

"She's big, ain't she," says Jackson, a slow-speaking, fireplug of a man dressed in his Forest Service green. "For my money, this is the most spectacular forest in the country."

The Bridger-Teton, in the parlance of the Forest Service, belongs to Reid Jackson. For a federal bureaucrat making $37,000 a year, he has enviable autonomy -- an almost unheard-of power to make decisions without being second-guessed in Washington. He's in charge of up to 200 employes. Without consulting his superiors, Jackson can sell up to 10 million board feet of timber, enough to build 833 houses. He can authorize major highways that would cut through the forest or stop dead in their tracks almost any timber or mining operation inside the Bridger-Teton.

While national forest policy is made in Washington, it's Jackson who decides when and how sizable portions of the largest wilderness in the lower 48 states will be chopped down and scoured for its natural resources.

By virtue of his job, Jackson is automatically one of the most powerful men in Wyoming, a state where the federal government owns 56 percent of the land. Jackson's boss in Washington, Assistant Agriculture Secretary M. Rupert Cutler, says the man in charge of the Bridger-Teton has "the best job in the Forest Service" in terms of authority to make his own decisions.

Even when Cutler has second-guessed Jackson, as he did last year is admonishing the forest supervisor for allowing timering in an area that interfered with a study of elk behavior, the reprimand came after the fact -- the timber was being cut down by the time Cutler decided it shouldn't have been.

Despite this estimable power, there's trouble today in Reid Jackson's empire. His forest is a "hot" one, perhaps the hottest in the nation. Timber and oil companies, politically astute preservationists and local activists are battling to control the future of the Bridger-Teton, and most of them have ugly things to say about Jackson.

"That Reid Jackson is one of the most pig-headed sons-a-bitches I've ever seen," says Floyd Schneider, a stonemason who lives in the south edge of the forest. Schneider has joined hundreds of his neighbors in claiming that Jackson is blindly allowing timber companies to rape the Bridger-Teton.

"Reid Jackson just doesn't understand the oil business. He doesn't communicate well. He is the type of guy who just wishes everything would go away," says Elmer Parsons, chief geologist for True Oil Company in Casper, Wyo.

True is one of scores of oil companies that have been sniffing around the Bridge-Teton because of something called the Overthrust Belt -- a geologic formation oilmen say offers the nation's best prospect for major oil and natural gas discoveries since Alaska's Prudhoe Bay.

"Reid Jackson's presence in this forest contains all the seeds for a truly enduring national tragedy. He cannot begin to comprehend the atrocious deed he is doing," says Henry Phibbs, an environmental lawyer who claims Jackson is ruining the country's richest wildlife area.

Pressures on the 53-year-old forest supervisor, a devout Mormon who works 11-hour days build almost every week, with Jackson's authoritive increasing muted by a tangle of laws aimed at protecting the environment and by president directives to cut more timber.

The pressures are exacerbated by the fragility of the mountainous forest he's supposed to guard. The six mountain ranges in the Bridger-Teton form the headwaters of the West's major rives -- the Missouri, the Columbia and the Colorado. The watershed, which lies on one of the most unstable geologic areas in the country, could easily be damaged by careless drilling, overcutting the forest or building too many roads. A blunder by Jackson could pollute rivers in the water-starved West for years.

Lately, Jackson says he often goes home at night and yells at his wife and children. One of his sons told him recently that his father didn't seem like a friend anymore.

A lot of the fun has gone out of the Forest Service," Jackson says sadly.

Founded 75 years ago by a mustachioed Yale graduate named Gifford Pinchot, the Forest Service has religiously followed his precept that forests should be "harvested" by man, not preserved. Pinchot called it "multiple use and sustained yield," which in theory means that forests can be used to supply wood, water recreation and minerals without being ruined as long as "professional" foresters run the show.

Because of Pinchot's thinking, which remains influential after three-quarters of a century, the Forest Service and the timber industry have always been chummy. Of all the powerful people in the Bridger-Teton who are demanding that Reid Jackson listen to them, timber company executives are the least likely to say mean things about Jackson.

Heightening the pressure to give timber companies special treatment, President Carter last June ordered a sharp increase in the timber harvest. Carter's decision, aimed at cutting skyrocketing housing costs, was an umprecedented change from Pinchot's "sustained yield" idea of cutting only as many trees as can be replanted.

As a result, Forest supervisors are under heavy administrative and political pressure to come up with timber according to assistant secretary Cutler. Because the harvest is so profitable earning the federal government nearly $828 million in 1979. Cutler says the White House and Congress are "preoccupied" with selling trees.

The men like Jackson who must meet the timber quotas are almost all career Forest Service employe. That's because Pinchot felt the best way to engender loyalty in his agency was to promote from within. So since 1905, virtually every key job in the service has been filled by men who've risen through the ranks.

Reid Jackson, who joined the Forest Services in 1952 as a smoke jumper, epitomizes the agency's promotion policy. His critics claim he also epitomizes the myopia of a stodgy bureaucracy that promotes people because of loyalty, not talent.

After 23 years of paying his dues in the service, Jackson was promoted five years ago to the job that nearly every member of the agency covets -- he was given his own forest. To be given the Bridger-Teton, he said, was a forester's dream.

Jackson moved to the forest "expecting it to be quiet" until he retired. He hadn't heard of the Over-thrust Belt and the legions of oil companies clamoring to drill wells. He didn't know there would be temporary delays in harvesting the forest because of proposals to classify it as an untouchable wilderdness. He didn't know about intimidating environmentalists who would accuse him of bad faith.

The dream soured immediately.

"Seems like the higher up you get in this outfit, the more the happiness disappears," Jackson says.

For both Jackson and the environmentalists, the greatest unhappiness is with oil. Jackson, a trained forester accustomed to selling trees, says oil companies make him nervous.

The companies that have turned the deserts of southwest Wyoming into a series of wealthy, wide-open boom towns are edging north to the forest, following the curve of the Overthrust Belt.

The Belt, which runs along the Rocky Mountains and stretches from Mexico to Canada, is a convoluted geologic formation of sedimentary rocks folded, cracked and thrust over themselves, trapping pockets of oil and natural gas. Because of that, two-thirds of the 3.4 million acres in the Bridger-Teton have been leased for oil exploration. Twenty-five exploratory wells will be drilled in the forest in the next two years. If major fields of oil and natural gas are found, hundreds more wells will follow. m

"The same geologic trends that are producing oil down in southwest run through the Bridger-Teton," says geologist Elmer Parsons of True Oil.

The Forest Service doesn't lease drilling rights to federal land (that's controlled by the Bureau of Land Management in the Department of Interior), but it does have control over what happens to the forest around the wells. The problem with any extensive drilling in the Bridger-Teton is that almost 80 percent of the forest has no roads. Massive oil exploration requires roads -- lots of them.

While a few dirt roads may seem an insignificant intrusion in the vast mountainous wilderness of the forest, game and fish experts, hydrologists and Reid Jackson claim that too many roads could mean disaster for the Bridger-Teton's most fragile resource -- the greatest population of big game animals in North America.

There are an estimated 25,000 elk, 6,000 moose, 27,000 mule deer, 2,000 antelope, 1,000 black bears, 50 grizzly bears, 1,000 bighorn sheep and 30 mountain lions in the forest. In addition, there are wolverines, lynx, river otters, trumpeter swans and ospreys. Endangered animals include Northern Mountain wolf, the whooping crane and the bald eagle.

Many of the big-game species migrate twice a year across what is called the Greater Yellowstone eco-system, moving south out of Yellowstone Park in the fall and traveling through the roadless forest to the winter feeding grounds of Jackson Hole for the winter. Roads, according to fish and game experts, frighten the animals and make hunting too easy.

"If there are too many roads, there are hundreds of places for hunters to go in their pickups, sip their coffee, listen to their eight-track stereos and slaughter the elk that must move past these new slaughter lines," says Wyoming state Sen. John Turner, a wildlife biologist who represents the Bridger-Teton area in the state legislature.

Turner, who along with his two brothers, owns the Triangle-X dude ranch on the eastern edge of the Bridger-Teton, makes a lucrative living outfitting hunters for wilderness hunts. Roads would severely hurt his business. They would also shorten the hunting season (now two months for elk), according to the Wyoming Game and Fish Commission, and cut into the estimated $8 million a year that hunters from around the world leave behind in the Bridger-Teton area.

All the concern about animals is making the oil companies angry and costing them money.

"Who are we destroying when we move the animals back occasionally?" They'll come back eventually," says Lon Raymond, public lands coordinator for Amoco Production Co. out of Denver.

"It comes down to, Jesus, how much land are we gonna set aside? What is the greatest interest here? The Forest Service is simply uncertain about what is going on. They lean on the side of the environmentalists in every decision," Raymond claims.

Phil Hocker, an environmentalist and member of the Sierra Club's board of directors, couldn't disagree more with the man from Amoco. Hocker says the Forest Service is intimidated by big oil.

"This is what the oil companies are saying: We will give you an unknown low percentage of the nation's oil needs in exchange for destroying the Bridger-Teton," Hocker says.

Yet Jackson, the oil companies and even the environmentalists agree that a major oil or natural gas discovery will force open the forest. "There is no way we are going to say no," says Jackson.

The prospect of oil and roads -- roads built with somebody else's money -- has put smiles on the faces of timber executives here. Company officials, who've been battling with environmentalists for years over the right to build logging roads to get at virgin stands of lodgepole pine, will have a much more compelling pro-timber argument after oil companies build the roads.

Until last year, when the president opened up nearly 36 million acres of the national forest system to timbering, much of the Bridger-Teton had been off-limits to timber companies while the government considered what areas to designate as federally protected wilderness -- a designation timber companies regard as evil because it stops all logging operations.

About one-third of the Bridger-Teton is now wilderness or proposed wilderness under the president's plan. The rest can be managed for "multiple use." Timber companies say it's about time they had a chance to cut some trees.

"We have been loving this forest too much," says Bob Baker, a former Forest Service employe now in charge of finding timber for the Louisiana-Pacific timber mill. "If your mother was beautiful, would you preserve her in an alcohol bottle? That's what they want to do around here."

Yet over-zealous logging has caused serious environmental problems in the Bridger-Teton. The Forest Service in the 1960s allowed timber companies to make enormous, 1,000-acre-square clear-cuts of bug-infested trees. The land was devastated and some of the clear-cuts have failed to regenerate new trees despite repeated plantings.

Last year, Jackson received the first reprimand of his career for selling timber in a section of the forest where the Wyoming Game and Fish Commission was conducting a study of elk behavior. Cutler, who issued the reprimand but was too late to stop the sale, wrote that he was "deeply disturbed by both the failure to plan for protection of wildlife study values and to sufficiently inform the public . . ."

Jackson, who was startled and upset by Cutler's criticism, explains that he made the sale because "we were really having a problem coming up with timer to carry the industry."

But Cutler says marginal timber stands in the Bridger-Teton are not worth endangering what he calls one of the nation's "showcase forests. We cannot let the tail wag the dog. We can't overcut this forest to keep a mill operating."

Jackson acknowledges that the assistant secretary has ordered him to stay away from controversial timber cuts in the Bridger-Teton. But the forest supervisor says that's a "pretty big order" considering all the people who are already angry with him.

Now, Jackson has decided to sell timber in the southern part of the forest, a sale that has provoked formal objections from local government leaders, from the Wyoming Game and Fish Commission and from local residents who all claim the sale will hurt the local elk population.

Caught in the vise of conflicting interests and, for the first time in his career, forced to endure criticism from a political appointee, Jackson says he will rely on his Forest Service "professionalism."

"I would stake my professional reputation on the way we are cutting trees now. I predict that people someday will say we should have cut more."