LOOK AT A CITY—say, this city—and you see a human drama: 600,000 people scrambling for money, power, sex, love, and whatever else they’re here to get. But step back and take a longer view, from a satellite or even a bird’s-eye perspective, and you’ll see another power struggle unfolding—the contest between trees and everything else that covers the ground. It’s a struggle waged in nearly every corner of the urban environment. It colors issues ranging from transportation and development to health and class relations. And sometimes it turns civic politics upside down.

Everyone pays at least lip service to the good things trees do for us. They shade and cool us. They clean the air and capture storm water, reducing flooding and pollution runoff. (The city values these two benefits at $5 million and $20 million a year, respectively.) They provide habitat for songbirds and other wildlife. They capture carbon, reducing global warming. And, by the way, they make us feel good and boost property values; been to Las Vegas lately?

Before humans began clearing the land, trees held sway here; 200-foot firs and cedars thronged to the water’s edge. They may rule again after humans depart. But in the interim, they’ve been losing badly. By 1970, Seattle’s tree canopy was calculated to have shrunk from nearly all to just 40 percent of its territory. That was, and still is, the canopy share that the pro-tree group American Forests recommended for rain-blessed cities like ours. But today that coverage has fallen below 23 percent—despite recent growth, in number and in total coverage, in street trees, which the city both plants and encourages residents to plant.

Trees have fared much worse on private property, especially property undergoing development. In recent years, average tree coverage fell from 30 to 18 percent on single-family lots that got redeveloped and from 18 to 5 percent on redeveloped multifamily lots. When builders pack in McMansions and town houses, they tend not to leave much room for trees. And the city had little say in the matter; its old tree-protection code restricted cutting only on undeveloped lots.

In 2007 the City, under Mayor Greg ­Nickels, released its first-ever urban forest master plan. It set a goal of raising canopy coverage to 30 percent in 30 years. To get there, the city council resolved to draft a new, more comprehensive tree code. That sent a shiver through two very different communities. Developers feared new rules would limit what they could build. Urban forest activists—a small but passionate contingent—feared property owners would rush to cut down valuable trees that might later be protected. Horror stories trickled in of owners doing just that. And so, in April 2009, the City implemented interim measures to prevent a rush for the chain saws while a permanent tree code was hashed out.

The interim rules bar cutting more than three grown trees in any lot in a single year, unless the lot is being redeveloped. And they ban cutting “exceptional trees”—trees with trunks above a set diameter for each species (two and a half feet for a cedar, fir, or elm)—unless they’re hazardous or they prevent an owner from realizing a property’s “full development potential.”

Last year the city council, on a motion from its president, Richard Conlin, delegated the task of drafting a permanent ordinance to the Department of Planning and Development (DPD), the agency that grants building and land use permits. And it established an Urban Forestry Commission (whose roster includes an arborist, a hydrologist, an economic development specialist, and other experts) to watchdog the process.


Read more about the people and issues shaping the Seattle landscape.