The 1906 San Francisco earthquake and fires kicked the cutting into overdrive. To meet demand for timber to rebuild the city, logging towns sprang up throughout the redwood range, and companies such as Pacific Lumber and Union Lumber flexed newfound industrial muscles. In place of teams of oxen, portable engines called steam donkeys dragged the massive logs, and narrow-gauge locomotives hauled them from the woods. Grainy photos from the "golden age" of logging show grinning timbermen with mustaches and suspenders standing atop felled trunks the size of Boeing 747s.
The felling of the great trees also helped spark the modern conservation movement. In 1900 concerned citizens formed the Sempervirens Club, whose advocacy led to the creation of Big Basin Redwoods State Park in 1902. In the 1920s the Save the Redwoods League began purchasing the groves that would become the backbone of California's redwoods parks, and it continues adding them to this day.
The last, and most intensive, burst of logging began after World War II, when the housing boom and a glut of cheap military-surplus equipment unleashed an army of bulldozers, log trucks, and chain-saw-wielding loggers onto the steep, unstable soils of the redwood forests. By the early 1950s mills were sawing more than a billion board feet of lumber a year, a level maintained until the mid-1970s. (A board foot is the equivalent of a slab of wood one foot square and one inch thick.) Clear-cutting and Cat logging, named after the yellow Caterpillar tractors that became the workhorses of the timber industry, unleashed a torrent of soil into streams from a latticework of logging roads and skid trails. Salmon runs dwindled, and so did other species that had existed in the redwoods for millennia. Today less than 5 percent of the roughly two million acres of virgin forest remains, mostly in parks and reserves throughout the range.
"The battle to save the redwoods has already been fought, and look, we're left with table scraps," says Steve Sillett, a forest scientist at Humboldt State University. "The challenge now is understanding how to improve management on the 95 percent of the redwood landscape that's just starting to grow."
Salmon and spotted owls aren't the only things to have suffered with the felling of the forest. Harvest rates in the redwoods have plummeted since the 1990s, when they were already half what they were in the 1970s. Though Fay and Holm spent nearly every night under the stars, every two weeks they'd hit little logging towns to recharge computer and camera batteries and download their data on portable hard drives—places like Korbel and Orick that once boasted several sawmills but are now lucky to have one still limping along. Rio Dell, a town of 3,200, has been luckier than most. It sits across the Eel River from Scotia, home to what was once a venerable timber enterprise: Pacific Lumber Company.