Seattle. A hub for the tech and e-commerce sectors? Check. A regional growth engine? Check. A poster child for urban tree loss due to rapid growth?

Well, two out of three ain’t bad.

It’s a misconception that has persisted for years, writes Dan Bertolet of the Sightline Institute. For instance, Seattle’s 2007 Urban Forest Management Plan, which set a citywide goal of 30% tree canopy cover by 2037, cited a decline from 40% coverage in 1972 to 18% in 2002.

That 40% figure, Bertolet writes, “was based on a misinterpretation of a 1998 study that was assessing the region, not just Seattle proper. And the 18% measured for 2002 was a blatant outlier on the low end, also unreliable.”

In fact, by multiple measures Seattle’s tree canopy cover has hovered around 30% in recent years, reaching or coming close to meeting the 2007 plan’s goals well ahead of schedule. It compares favorably to the two other major cities in the Cascadia region: Vancouver, BC and Portland, OR.

Bertolet acknowledges that Seattle’s most reliable new data on the change in tree canopy over time points to a 6% decline between 2007 and 2015. “Here’s the catch, though: most of the confirmed tree loss happened on land reserved for detached houses, the single-family zones that cover over half the city, but where population has barely budged for decades,” he writes.

Meanwhile, he adds, the same study found “no statistically significant change in tree canopy where the growth actually has been happening: the land zoned for commercial buildings and multifamily housing that absorbed the vast majority of Seattle’s new apartments, offices, and stores.”

Over the same eight-year period, all that construction helped make room for 76,000 additional residents and 65,000 new jobs, the equivalent of adding about half of neighboring Bellevue, WA to the population, writes Bertolet.

“It’s a remarkable success story: confined almost completely to the 18% of city land where multifamily housing is allowed—with no measurable impact on trees!”

All told, Bertolet writes, the record points to success in maintaining the city’s tree canopy, and argues against making drastic policy changes that could stifle homebuilding to preserve trees. “Seattle’s tree studies demonstrate that, contrary to what the casual observer might assume, cities can build up—a lot!—and still keep lots of trees around,” he writes. “And that’s great news, because trees bring immense value to city dwellers in numerous ways.”

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