Seattle embarks on a dramatic experiment in restoration
Ecologists try to make second-growth forests function like vanishing old growth
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A feller-buncher cuts trees down, strips them of branches and divides them into logs without trashing nearby vegetation or dragging logs over the ground
Seattle Public Utilities
SEATTLE, WASHINGTON — At first glance, the forest looks like an area in the initial stages of harvesting by a timber company. A stack of logs sits by a dirt road not far from a harvester-processor, a tractor-mounted machine with a 30-foot-long arm that cuts, de-limbs, and piles up trees. Behind the logs, stumps poke up through the understory of leathery-leaved salal. Farther down the road, a brush-covered track winds into a grove of telephone pole-sized Douglas firs, many painted with either a thin blue or thin red line.
This isn’t the work of loggers, however: Ecologists employed by the city of Seattle are behind it. Ironically, the goal of the so-called "45 Road Forest Restoration Project" is to start to reverse the negative impacts of a century of cutting throughout the Cedar River Watershed, the source for 70 percent of Seattle’s drinking water. Seattle Public Utilities, which manages this watershed, is experimenting with a variety of techniques that should make this young forest function ecologically more like the grand old-growth stands that once grew here.
The ecologists’ tools include selective thinning, tree planting, and practices that are more experimental, such as planting lichens and mosses in the forest canopy.
Jerry Franklin, professor of ecosystem science at the University of Washington, and one of the deans of restoration ecology, says the work in the Cedar River Watershed is on the cutting edge of forest restoration. "People suggest that once you walk away from (a forest) you can leave it alone and that it will take care of itself. It’s not true. Nature will adjust, but you won’t like the outcome. You’ll lose values. You’ll lose big old trees. You’ll lose owls. You’ll lose watershed protection."
Water for fighting, and drinking
Understanding the scene in Seattle’s watershed requires a trip back to June 6, 1889, when John E. Back let his pot of glue boil over onto the stove of a downtown Seattle cabinet store. Back, described in the Seattle Post-Intelligencer as "a thick-set blond of mediocre intelligence," tossed water on the flames, which merely spread the fire to wood shavings on the floor, and set the building ablaze. Within the hour, flames had spread to nearby sawmills, lumberyards, and creosote-coated pilings supporting city streets and buildings.
Fire crews arrived quickly, but when a messenger ordered water pumping crews to "Give her all she’ll take," they responded, "We’ve already given her all she’ll take." There wasn’t enough water. Before the fire could be contained, it burned over 115 acres and destroyed the downtown retail and industrial core. Thirty-two days later, Seattleites approved a $1 million bond to form a publicly owned waterworks not only for firefighting, but for drinking.
The source of that waterworks is the Cedar River, which flows west out of the Cascades from headwaters about 50 miles east of the city. Over the century following Seattle’s "Great Fire," the city acquired all of the 90,546-acre Cedar River Watershed. Because the city lacked the funds to buy the land and timber rights together, however, it allowed timber companies to clear-cut 83 percent of the forests.
Logging in the watershed only ended in 1997, four years after Seattle began work on a habitat conservation plan to protect the threatened Puget Sound chinook salmon and 82 other species (HCN, 8/30/99: Salmon and suburbs struggle over a Washington river). Early drafts of the plan proposed paying for protection by logging even more of the watershed. This inspired Seattle Mayor Paul Schell’s famous quip about a city councilwoman who supported cutting: "So she wants to pay for saving the trees by cutting them? I’d like to give (the watershed) to the next generation."
Environmentalists questioned whether cutting trees was worth the estimated annual savings per family, equivalent to the cost of one latte. The final plan, passed by the city council in 2000, banned all commercial logging in the watershed.
Leap-frogging toward old growth
To meet the requirements of the 50-year habitat conservation plan, Seattle Public Utilities is working to create better fish habitat, remove roads and replace culverts, while keeping the drinking water clean for its 1.3 million customers. It is also cutting trees; despite the ban on commercial logging, the plan does permit thinning for ecological reasons.
Last fall, workers cut about a quarter of the 45 Road forest, which, like much of the watershed, was dominated by a dense forest of even-aged Douglas firs. Unlike an old-growth forest, these woods lacked standing and fallen dead trees, uprooted trees, canopy gaps, and a diversity of tree species and sizes. As a result, the forest wasn’t providing much habitat for imperiled species. The challenge was to get to old-growth conditions without waiting 100 years.
"As you can see, in some areas we didn’t cut any trees. In others, we cut a few, and in several patches, we removed almost everything," says Melissa Borsting, a plant ecologist for Seattle Public Utilities. Foresters call this "variable density thinning" or "skips and gaps." The uneven patterns break up the second-growth, leapfrogging toward the conditions found in a more mature forest. This winter, restoration crews also planted nearly 7,000 red alder, bigleaf maple and western red cedar seedlings.
In the next restoration project, due to begin this year, crews may attach lichens to trees and import soil and logs from old-growth forests.
"Restoration is an experimental science. We have good ideas but we don’t know exactly how to make old growth," says Jim Erckmann, the utilities’ watershed ecosystem manager. But, he adds, "because we don’t have an economic incentive, we can be more experimental."
Franklin, at the University of Washington, also praises Seattle for taking the initiative. "(Local control) is an anathema to a lot of us. That’s one of the approaches that we are going to have to think more about in this century. This isn’t the 20th century. This isn’t timber vs. owls."
The author writes from Seattle. His book of essays about Seattle, The Street-Smart Naturalist, will be published in 2005.
Jim Erckmann Seattle Public Utilities Watersheds Management Division, 206-233-1512, www.ci.seattle.wa.us/util/
Jerry Franklin 206-543-2138, [email protected].edu.
