A genial, wide-eyed nature-lover who happens to be Yellowstone's chief ranger writes of the Park's natural wonders and troubles in this entertaining if corny report. Sholly, whose dad was chief ranger at Big Bend National Park, moved into Yellowstone with his wife and kids in 1985. Here he was in his boyhood dream: in charge of 2.2 million acres of ``the first, the oldest, the most famous, the most respected, and certainly the most treasured of the world's national parks.'' For the most part, this is a paean to Yellowstone's great beauties- -its canyons, geysers, forests, bison, elk, moose, bear. Sholly loves 'em all. He also deals in human drama, as he and his staff confront poachers, toxic spills, protesters, even a hostage-taker at Old Faithful. Usually, the ranger holds the middle ground on hot disputes, such as cattle-ranchers vs. bison-lovers, although he favors banning kayaking and hang gliding from the park as a disruption to the wildlife. The centerpiece of his tenure, however, is the terrible fire of 1988, which pits locals against rangers and environmentalists against themselves, and which Sholly calls ``the ecological event of the past 300 years.'' Event--not disaster: Sholly is among those who believe the fire was necessary for Yellowstone's ecological health. Simple, cozy, unadorned: like a night around a campfire, somewhere in those gorgeous Yellowstone mountains.