Another group practicing ecological forestry, Evan Smith's Conservation Fund, bought 40,000 acres of industrial timberlands in the Garcia River, Big River, and Salmon Creek watersheds to keep the trees from becoming vineyards and subdivisions. The organization plans to use uneven-­age selection forestry to restore aquatic habitat by reducing erosion into the streams. To help with financing, it is selling millions of dollars' worth of carbon-reduction credits to Pacific Gas and Electric Company as well as to several investment firms.

California's Air Resources Board now plans to adopt an updated carbon protocol for forestry, hoping to attract the industrial timber owners. "If we can get the carbon incentives right, we can double or even triple our inventory in the redwoods," Mike Fay says.

On a day when the early morning sun is filling the mist-shrouded canopy of Prairie Creek Redwoods State Park with an iridescent glow, Mike Fay hooks his ascender to a climbing rope and "jugs" up a truly massive redwood to talk to one scientist who is convinced of the value of letting redwoods grow big. Steve Sil­lett has made a name for himself by finding, climbing, and studying the tallest trees on the planet. He has meticulously measured hundreds, from their mighty bases right up to the individual needles at the top. At 138 feet up, Fay passes a fire cave big enough for two grown men to stand in amid a thicket of reiterated trunks and branches—battle scars from centuries of skirmishing with fire and wind. Higher still, epiphytic ferns and huckleberry bushes grow in deep canopy soils, while a myr­iad of mosses, liverworts, and lichens cover the bark. This tree, at 301 feet, isn't even close to the world's tallest, at 379.1, but accord­ing to Sillett, who is waiting for Fay at an opening in the canopy right at the very top, it is "super juicy"—loaded with canopy soils and biodiversity. From there the two men peer out upon a nearly unbroken expanse of huge redwoods, with one clear-cut barely visible to the south.

The mantra of industrial foresters has long been to grow trees as fast as possible to maximize the return on investment and provide a steady flow of wood products to market. For them, the most profitable time to cut redwoods is at 40 to 50 years, even though such young trees contain mostly soft, low-quality sapwood, with little of the redwoods' legendary resistance to rot. But after coring and measuring two dozen trees—95 feet to 370 feet tall—from canopy to base in Humboldt Redwoods State Park, Sillett discovered that a tree's annual rate of wood production increases with age for at least 1,500 years. More important, the older it gets, the more high-quality, rot-resistant heartwood it puts on. The bottom line: Redwoods produce more wood, and better wood, as they age. Sillett says this is true for the tallest eucalyptus trees in Australia too, and he thinks it may be true for other trees around the world.