His ruddy face creased in a proud "That's my boy" smile, forester Dick Ford stretches to measure a bushy Douglas fir sapling. "Over nine feet tall!" he says with delight.

Normally, a nine-foot sapling would hardly be cause for remark at a tree farm. But this young tree is remarkable because it's growing on a hillside just a dozen miles from Mount St. Helens -- a hillside that was turned into an ashen moonscape when the famous volcano blew its top with 24-megaton force five years ago today.

The healthy Douglas fir, and the rich stands of maple, alder and willow trees sprouting around it, are part of a flourishing natural rebirth that has amazed the experts and rewritten the textbooks on recovery of devastated ecosystems.

"Scientists were astonished by the immense destruction wrought by the volcano," says Steven Brantley, member of a U.S. Geological Survey team studying the mountain. "Now . . . scientists are astounded by the remarkable rate of plant and animal recovery occurring within the devastated area."

The 150,000-acre "blast zone" northwest of St. Helens -- an area slightly bigger than all the land inside the Capital Beltway -- that became an instant graveyard five years ago has become a vibrant young forest where most, but not all, of the native animal species have again found a home.

"Mother Nature and Father Time got together and made a mira- cle," says Mike Monson of Weyerhaeuser Co., the biggest land owner in the blast zone. "And man helped a little, too."

Weyerhaeuser, the U.S. Forest Service and the state of Washington have mounted a huge effort to reclaim the region, hauling away tens of thousands of fallen trees that carpeted the ground like a giant's toothpicks and planting millions of trees.

But the most important regenerative force has been nature's.

Within months after the eruption, the bleak dead zone began to sprout with primary species like fireweed, thistle and pearly everlasting. Without the normal shade of the forest cover, these low plants grew prodigiously.

The plant life, in turn, provided unusually rich forage for animals ranging from moles and field mice to coyote and elk. "That low forage, that's just like the salad bar at Denny's for the elk and deer," Monson says.

Hungry animals migrating to this natural salad mixed the six-inch layer of ash that covered the ground into the soil, providing a rich, permeable setting for shrubs and trees.

The banks of the Toutle River, denuded by massive mud flows that continued for months after the eruption, now bristle with thick clumps of wispy red alder trees, an important nitrogen-fixing species.

"Those alder will build the soil back faster than any fertilizer man could put in there," says Ford, a Weyerhaeuser reforestation specialist who started planting fir seedlings here within a month of the blast. The foresters and ecologists who have witnessed the five years of rebirth say the most stunning change is the reappearance of color in the blast zone.

"I remember in June of '80, the whole world for miles and miles was all one color -- gray," Ford says. "It had the appearance of death. You just thought nothing would come back."

Looking out on this fifth anniversary from Windy Ridge, a tourist-choked promontory northeast of the volcano, the eye still takes in large splotches of deadly gray, particularly in the direct arc of the blast, where mud, ash and pumice were deposited 200 feet thick.

But the predominant hue is the pale green of young life. What was once a sea of ash is now a soft green carpet mottled here and there by bright crimson fireweed and golden buds of Scotch broom.

The most stunning contrast can be seen just off Highway 504 north of the tiny town of Toutle, about 30 miles from St. Helens, where the two forks of the Toutle River meet.

The south fork, which was not in the path of the volcanic blast, is a glistening blue stream. The north fork, which was clogged with a cubic mile of debris by the eruption, is a mucky, muddy gray.

The north fork is the focus of one of the lingering controversies here about continuing efforts to clean up after the blast.

The Army Corps of Engineers wants to build a $300 million dam on the Toutle just below St. Helens to trap the sediment. Some local residents are violently opposed, saying the river eventually will cleanse itself.

Also controversial are various plans to develop a tourist industry around the site of the mightiest eruption the nation has seen in this century.

It's an ill volcano that blows no good, and the Mount St. Helens eruption has created a burgeoning visitor trade. "We used to be a place mainly for local hunters and hikers," says Thom Corcoran of the Gifford Pinchot National Forest. "Now we're an international attraction like Yosemite or Yellowstone."

The towns surrounding St. Helens are now dotted with businesses like "Mount St. Helens World," a converted bowling alley in Kelso where one can buy a soup bowl made of "genuine Mount St. Helens ash" and "microwave and oven safe" for $7.99 or a videocassette of the eruption for $39.95.

Highways throughout the region are being widened and paved to accommodate migrations of school buses and Winnebagos. The Forest Service has put out a 300-page plan for tourist facilities in the Mount St. Helens National Volcanic Monument, a 110,000-acre preserve surrounding the crater.

But local groups have raised complaints about the plans, including the Forest Service proposal for an aerial tram over the lava flow. Critics say this would give a natural wonder "a Disneyland atmosphere."

When Mount St. Helens erupted at 8:32 a.m. Pacific time on Sunday, May 18, 1980, the blast blew its top 1,300 feet to smithereens, turning a graceful cone into a jagged, smoldering crater.

The force of the blast blew down tens of thousands of acres of trees. The concurrent heat wave raised temperatures to nearly 600 degrees Fahrenheit, literally boiling a nearby lake and cooking every animal in the blast zone.

Fifty-seven people are dead or missing from the blast, including 82-year-old Harry Truman, whose lodge at the tip of Spirit Lake just north of the mountain is buried under a 20-story mound of mud.

Beyond the blow-down, thousands more acres of trees were instantly killed by the heat wave. In the preserved area, those charred trees still stand, looking like burnt candles atop an enormous black birthday cake.

Today a thin plume of bluish steam spiraled skyward from the crater. Geologists say the mountain is still a live volcano. Tourists are given a map showing emergency evacuation routes.

"We don't have any sign of another big blow," says the Forest Service's Corcoran. "But then, she gave us a surprise, a big surprise, once before."