While the hordes attending the annual people-a-thon in the Grand Teton- Yellowstone National Parks area were inching along in bumper-to-bumper traffic last summer lamenting their fate, a small group of plant lovers and I hiked in the solitary splendor of the Bighorn Mountains, a short distance away — often going an entire day without encountering anyone else.

I was traveling with nine amateur and expert botanists who shared a love of rock gardening and alpine wildflowers. We were on a tour benefiting the T.H. Everett Rock Garden of the New York Botanical Garden, and while we had an expert along to help us identify the plants, this is a trip that anyone could easily duplicate.

Our mission was to search out native American alpine wildflowers — species that grow mostly at or above timberline. The Bighorns are particularly rich in these floral gems, some of which appear no place else in the world. Many European botanists prize the area as highly as the Pyrenees and the Alps, so you're likely to cross paths with some of these enthusiasts — on their hands and knees — photographing our native treasures.

The Bighorn National Forest, which encompasses much of the mountain chain, consists of more than a million acres managed by the U.S. Forest Service, which allows both recreational and commercial uses of the land, including grazing. Unfortunately, these priorities sometimes conflict, and the dual usage can place a strain on the environment, taking a heavy toll on its plant life. In winter, activities like snowmobiling can damage fragile mountain tundra beyond any hope of reclamation. During the summer, thousands of sheep are trucked in to graze the mountain meadows to a nubbin, with the resultant loss of many plants. It's a problem that greatly disturbs environmentalists — often pitting them against locals who must make a living off the land — yet there is no easy solution.

Our plan was to make a circular trip: we'd fly into Billings, Montana, drive south to Wyoming, explore the Bighorns, then swing north, making a slight jog west to the Beartooth Mountains, to cross the fabled Beartooth Pass, which straddles the Wyoming-Montana border, before returning to Billings. The timing of our weeklong foray would be important. At these high elevations, summer allows the flowers only a brief six weeks or so to emerge from the snow, bloom, and disperse seed to perpetuate themselves. We chose the second week of July, which turned out to be perfect. (Friends who'd made the attempt a week earlier faced an unexpectedly late 14 inches of snow and weren't able to cross the Beartooth Pass.)

At Billings Logan International Airport we picked up three four-wheel-drive station wagons and headed south through the verdant rolling prairie of the Crow Indian Reservation. Cutting west on Route 14, we began to ascend the Bighorns in heavy rain and fog.

As we neared the top, the rain tapered off and the fog began to lift, its tendrils revealing tantalizing carpets of electric-blue delphinium and purplish-blue lupine beneath black-green conifers that hugged the road.

Our destination was Burgess Junction, Wyoming, which seems larger on the map than in reality, for it's composed solely of an intersection, a small trailer park, and an eight-room motel called Bear Lodge. Nearby, a larger building, owned by the motel, contains a one-room general store, a small bar, and a restaurant. Be forewarned: accommodations at Bear Lodge, while comfortable, border on the spartan. Most rooms have two double beds, a straight chair (if you're lucky), a shelf, and hooks on which to hang your clothes. The tiny bathrooms are clean and have adequate hot water, a blessing savored after a long day hiking in search of horticultural treasure. (The latter is a bit of hyperbole, for you can find wildflowers by simply walking across the road from the motel to explore the ditch.) Still, driving the graded, generally well maintained secondary roads will take you to places of great natural beauty, most of them displaying an embarrassment of flowers. When you find a likely spot, park at the side of the road and hike to your heart's content.

Hunting for flowers in the Bighorns isn't difficult; they'll surround you. Identifying them is another matter. We were fortunate enough to have our horticulturist along to guide us through the jungle of Latin names and point out the distinguishing characteristics of each species. But even he carried along a good field guide to wildflowers of the Rockies, as each of us did.

Despite the fact that the plant you see today may become sheep fodder tomorrow, collecting specimens is considered an ecological no-no and frowned on in most of the alpine world. (Many botanists photograph their discoveries; a good camera and plenty of film are indispensable.) Collecting a small amount of seed is allowed, however, provided you don't strip all of it from a plant. Some of these plants can be grown in a garden setting, particularly if started from seed.

The alpine meadows of the Bighorns are blanketed with mats of phlox species interwoven with astragalus, a member of the pea family, and a host of other wildflowers. Seepy bog areas where mountain springs bubble to the surface are studded with clusters of buttercups and monkey flowers, and if you're lucky, in drier areas you may even come across "Calypso bulbosa," a delightful little ground orchid just four inches tall.

The true gems, though, are usually found in places that seem the least promising. Look for stretches of rocky white rubble where the limestone cap that covers these granite-based mountains has been ground to small fragments by natural forces. At first glance this harsh terrain seems barren, yet it provides the quick drainage that most alpine flowers demand.

One of the loveliest is a barely three-inch-high dwarf columbine, "Aquilegia jonesii," which smothers its blue-gray tightly furled foliage with large purple flowers. Growing in limestone rubble, it steadfastly thumbs its nose at gardeners who try to coax it to flourish at lower elevations. It will grow, yes, but it rarely blooms in such circumstances and is only a pale shadow of itself in its natural habitat.

Another native that wins most hearts is the alpine forget-me-not "Eritrichium aretioides," a borage that can bring strong men to their knees to photograph its incredible blue flowers. Reginald Farrer, the great turn-of-the-century English rock gardener, called it "the king of the Alps," sketching its glories in wildly purple prose. Still, you can understand his passion after you've come upon swaths of forget-me-nots, rich tapestries of cerulean blue interlaced with the hot pink of "Douglasia montana" and the sharp yellow of draba, a tiny bun-shaped member of the mustard family.

It's worth a special trip to see Medicine Wheel, an archaeological site whose prehistoric origins remain largely unknown. A Native American shrine still revered today, it consists of a circle with radiating spokes made of limestone rocks set flat in the ground, much like a wagon wheel. The location, on a breezy ridge of Medicine Mountain, is surrounded by a barbed-wire fence from which hang dozens of contemporary offerings — bits of cloth, animal skin, beads. The U.S. Forest Service has built an information center about a half mile below the circle where you must park and then hike up without wandering off the road — a shame since the shattered limestone on this windblown ridge forms a spectacular natural rock garden hosting a bounty of beautiful plants.

We spent three days tramping the Bighorns, then descended the dizzying western slope of the mountains on Route 14A to the dry flatlands. There we cut north to the steep red sandstone cliffs of Bighorn Canyon, a rugged channel carved over the centuries by the mighty river that rushes through it.

This detour presented not only magnificent scenery but a range of desert wildflowers we hadn't found in the mountains. On the sandy meadows edging the road we discovered several varieties of penstemon, the colorful beardtongue that is one of the glories of the West, along with "Eriogonum umbellatum," a mat-forming member of the buckwheat family that surrounds itself with a corona of luscious cream or yellow blooms.

Finally, we drove north on Route 310, then doglegged over and down to Red Lodge, Montana, our base of operation for the next four days. This classic Western town has a wide range of accommodations (it's a ski resort in winter, and in summer serves as an eastern gateway to Yellowstone, some 70 miles away). Rising from the valley floor where Red Lodge nestles, the stretch of U.S. 212 that leads to Yellowstone takes you over the 10,947-foot Beartooth Pass, an awesome sight with some of the most dramatic scenery in the Rockies. Steep switchbacks allow room for several cars to pull off in places where you can view the scenic splendor or, as we did, explore the scree to photograph the plants. At first glance the rocky scree seems barren. On close inspection, however, you find the crevices between the crushed rock filled with wildflowers.

Alpine buttercups, tiny primroses, and columbine nestle in the limestone. Another pocket reveals a different form of the alpine forget-me-not "Eritrichium howardii." Yet another choice find is purple saxifrage, "Saxifraga oppositifolia," a tight little cushion whose leaves are arranged opposite each other like the four points of a compass. In bloom it wraps itself with purplish-pink blossoms that are breathtaking.

Scrambling over the scree is not for the timid, because the slopes are steep — often perilously so — and nothing anchors the loose rock. But for the adventurous and certainly for plant lovers, climbing the scree is a must, since the plants found here are the equal of any in the world. Indeed, many of my European rock-gardening friends, who make annual pilgrimages to the Beartooth Plateau, find it difficult to understand how most American plant enthusiasts have overlooked it.

The pass, even so, isn't the only gardening game in town. Virtually any of the side roads will yield spectacular wildflowers. One of our final excursions was a dirt road leading to Red Lodge Mountain which was closed for the season. Fortunately, we were able to locate the manager, who allowed us to drive up a service road to the top of the ski lift, where we parked. It was late afternoon and a light fog was just beginning to creep in. Coming over a low saddle, we found ourselves knee-deep in flowers filling an alpine meadow of staggering beauty.

Great patches of mountain clematis sprawled over the pine duff blanket underneath low-growing trees stunted by the altitude. The rich blues and purples of delphinium and lupine were punctuated by the sharp yellows and oranges of buttercups and mountain poppies. Pasqueflowers of myriad hues (we counted at least five) were interlaced with ground orchids, gentian, and Indian paintbrush in neon shades of yellow, red, and pink. The only thing missing was Julie Andrews in her dirndl singing "The Sound of Music," and I assure you we didn't miss her that much.

Despite the fog, which precluded really good photography, our mountain meadows experience was so exhilarating we decided we had to share it with two members of the group who'd stayed behind. The following morning, before driving 60 miles to the Billings airport, we swung back to the spot for a second brief look. The early fog was just beginning to lift in the morning sun and the scene was everything we had promised our friends — a fitting end to a splendid trip and a sight none of us will soon forget.

We stayed in two places, making day trips from each: Bear Lodge (Burgess Junction, Wyo.; 307/655-2444; doubles $39) and the Rock Creek Resort (Hwy. 212, five miles south of Red Lodge, Mont.; 406/446-1111; doubles $79 - $84). We used an excellent guide to the region's wildflowers: "Alpine Wildflowers of the Rocky Mountains" by Joseph F. Duft and Robert K. Moseley (Mountain Press Publishing).

New York-based writer LAWRENCE THOMAS is on the board of the North American Rock Garden Society.