But those trees continue to fuel controversy, this time over whether people should be allowed into the cathedral-like ancient groves located some 200 miles north of San Francisco.
The story illuminates one of the environmental movement's biggest blind spots: its failure to paint people into their image of nature. Treating people as damaging invaders becomes self-fulfilling prophecy that alienates the public from protecting the land.
Since the land entered public ownership at a cost of $380 million in federal and state funds, the federal Bureau of Land Management has kept the ancient forest closed to the public, allowing visitors only into the younger stands that surround the central groves.
The agency floated a plan last year that would permit visitors to hike along the edges of two ancient stands, but that proposal has drawn fire from the very environmental groups that spearheaded the drive to protect the forest.
"If I had my druthers, the place would be entirely off-limits to human beings," says Karen Pickett of the Bay Area Coalition for Headwaters. "The footprint of a well-intentioned person sinks just as deeply as anyone else's."
It is true that hikers make noise, spooking animals and keeping them away from habitat alongside trails. Visitors drop food scraps, which attract jays and ravens, which in turn eat the eggs and fledglings of an endangered sea bird, the marbled murrelet.
"This is more of a reserve than a recreation area," says the BLM's Lynda Roush, who will issue a final decision this summer.
For many activists, a deep distrust of people and their effect on the wild lies behind the biological arguments. "One of the ideas I had in helping to save Headwaters was that it would be untouched," says Josh Brown, a former Earth First! organizer.
These are hikers we're talking about, not snowmobiles in Yellowstone National Park. The activists' view represents a striking pessimism about our species: a belief that the very presence of human beings is damaging to nature. It implies that we can never evolve beyond our current role as despoilers.
Ironically, the activists themselves have visited Headwaters, Brown about two dozen times. At first, I wondered how they could try to prevent others from doing exactly what they have done. But then I ventured to the groves myself, and understood a key point: They'd been changed by the experience. Paradoxically, they can't trust others to be similarly affected.
On a ranger-led hike to the edge of Headwaters, I was joined by musician Francine Allen, who had hiked into the groves several times while they were still in timber company hands, helping Earth First! to reconnoiter the area.
To avoid detection, she said , she'd had to hike four miles up a steep gravel road by night and duck into the deep woods at the first opportunity. This time, we rode in a government van and sauntered along in broad daylight.
"It's weird to walk along talking so loud," Allen observed. "We used to talk like this," she said, lowering her voice to a whisper. "We revered the forest. Now it's too easy, too simple to get here."
The difficulty of sneaking into Headwaters Forest while it was still privately owned made people behave as though the forest were sacred as well as dangerous. They could travel only at night, scouting ahead to make sure the timber company's security guards weren't awaiting them.
It was a place of awe and humility. Two ingredients in that experience were the hikers' careful preparation for the journey, and the knowledge that there was something in the forest -- guards -- probably fiercer than they were. In effect, they weren't the top species in the food chain; they were one species among many.
Few of us care to trespass on private property for the sake of developing that reverence. It can come instead from the knowledge that grizzly bears, cougars, or simply the unpredictable elements of nature may lie around the next bend in the trail
But the only way we will be changed by those greater powers is to immerse ourselves in them. Banning people from the place where that transformation could occur will leave us unreconstructed, and as base as the misanthropes assume us to be.