The densest neighborhood in the city overlaps with the most tree canopy coverage in the city.
I love my Capitol Hill neighborhood in the spring. The tree canopy, the tree canopy, the magical tree canopy!
The quantity & quality of Seattle’s tree canopy is a proxy for the city’s endless existential debate over density: Opponents of increased density say increasing development diminishes canopy, and I say the city’s tree canopy is flourishing right now, in the heat of a development boom.
I can’t help thinking tree canopy is consistent with density because I live in one of the city’s densest, multi-family zones, and whenever I’m out walking or biking, I’m repeatedly startled by how green my neighborhood is. (The Heart of Capitol Hill , with 54,850 people per square mile is the densest section of Seattle; though on average, Belltown, First Hill, and Lower Queen Anne are denser at 38,000 people per square mile, 27,000 people per square mile, and 16,000 people per square mile respectively versus Capitol Hill’s 15,000 people per square mile on average.)
It turns out my sense that density overlaps with heavy tree canopy isn’t just my anecdotal inkling of things.
The Seattle Office of Sustainability & the Environment’s 2016 Seattle Tree Canopy Assessment found that my neighborhood is in the section of the city with the highest percentage of canopy coverage, 36 percent canopy coverage. (I’m leaving out “Delridge Neighborhood” in Southwest Seattle, which truly came in 1st place at 38 percent, because it includes the largest swaths of dedicated green space in the city.)
The study certainly isn’t precise about neighborhoods; my Capitol Hill neighborhood, for example, simply fits into a broader region that’s labeled “East.” But the study also showed that all the regions with larger single-family zones—”Ballard,” “Central,” “Northwest,” “Northeast,” “Southeast,” “Southwest,” and “North”—all have lower canopy coverage than the “East” region.
Admittedly, at 35 percent canopy coverage, the “North” Seattle region—the region that has the most exclusively single-family zoning—comes in a close second place to my “East” region. But still, with “North” Seattle coming in second to “East” Seattle (which, including super dense First Hill, has significantly more land zoned multi-family than the “North,” according to the report), I’d say the burden of proof in the great tree canopy debate lands on the people who disparage density for its supposed negative impact on greenery.
I should note: The study did find that adding development slightly lowered canopy coverage in single-family zones. However, that finding came with a big asterisk saying the finding was “not statistically valid.”
Ultimately, the study DOES say single-family zones have more tree canopy coverage than multi-family zones…
But the study also says this: A dominant 56 percent of the city is zoned “Single-Family Residential” … versus just 11 percent zoned “Multi-Family Residential”… This means (with so much more land to start with!) the “Single-Family” zones have more of the City’s parks, green spaces, and school play fields overall to factor into the greenery mix.
Footnote: It’s important to remember that property owners in single-family zones have the rights to cut down trees in their yards. People in multi-family zones don’t have that leeway. That’s probably why my multi-family neighborhood is so wild with trees.