Growth of Moss Pushes Limits in Seattle

Tai Koenig, left, and Mitch Jacobsen clear a Seattle roof. Mr. Jacobsen is a window cleaner but says, “There's money in moss.”

SEATTLE — There are many ways to measure the relentless precipitation and enduring gloom that have cloaked the Pacific Northwest the past few months.

Psychology: “You just have to carry on,” said Molly Corrigan, soaked citizen of this so often sunless city.

Utility: “Abundant Snowpack Assures Healthy Electricity Supplies,” trumpeted Seattle City Light, which generates most of its power through hydroelectric dams.

Danger: “Washington family survives avalanche in vehicle,” read a recent headline.

Little League: “Field closed,” say the sad signs on the diamonds.

And then there is the evidence procreating beneath your feet, through your yard, up on your roof, down your gutters and into your dreams: the march of the moss.

“The spores were really active this year,” said Robert Braid, caretaker of the Bloedel Reserve on Bainbridge Island, across Puget Sound from Seattle.


Inara McEwen, sitting on a bench by a reflecting pool at the reserve, noted the diversity: “There’s the moss that grows on trees, and there’s the moss that grows in your car.”

When Mr. Braid speaks about spores being active, what he is really saying is that after a particularly rainy winter (thank you, La Niña) and now amid a particularly rainy early spring (thanks again), the atmosphere has been ideal for moss to multiply. And so it has been doing just that.

That means this wet region is once again confronting its moss divide.

“So many of the calls we get are from people who actually want to get rid of moss,” said Sue Hartman, who helps answer the gardening hot line run by Seattle Tilth, which promotes organic and sustainable gardening. “But this being the Pacific Northwest, moss is really kind of a native plant. I personally love moss, and my pals here at Tilth also love moss.”

Noting that this has been “an extraordinary year for moss,” Ms. Hartman said Seattle Tilth tried to provide “a little therapy” for people whose image of a lawn or garden bed does not necessarily include moss.

“When we see something that doesn’t look right to us, our first instinct is we need to correct it,” Ms. Hartman said. “But if moss is growing somewhere, it’s growing there for a reason. Perhaps you’re trying to grow grass in a place where grass doesn’t want to grow.”

Of course, moss and grass are not always at odds. Sometimes moss grows on roofs, then grass grows in the moss and an ecosystem is born.

“We’ve just gotten more and more into moss because it’s been so much wetter,” said Mitch Jacobsen, co-owner of Better Window Cleaning Seattle. “There’s money in moss.”

Mr. Jacobsen and an employee, Tai Koenig, were about to scale the roof of Ms. Corrigan’s two-story home on another drizzly morning in Seattle’s Ballard neighborhood. For about $400, the men would rake and clear the roof, clean the gutters and then treat the roof with chemicals to slow the inevitable regeneration of moss.

Ms. Corrigan said that she and her husband were having the roof cleaned mostly for maintenance, but that they also hoped removing its soft mossy habitat would discourage a pair of raccoons known for their own procreative endeavors — “rooftop romance,” she called it. Neighbors had taken notice. Photographs were well-circulated.

“I don’t think they will like the rough asphalt,” Ms. Corrigan said of the roof tiles.

This push and pull between people and the elements here is constant but not always predictable. Mr. Jacobsen said his company often wrestled with what chemicals to use on roofs. While some residents have no problem with powerful phosphates, others who want moss removed worry about the runoff — particularly the increasing number of people who capture roof runoff in cisterns to water their vegetable beds. Then again, some of the newest “green” houses have roofs with moss deliberately planted on them.

At Bloedel Reserve, which claims to have the largest moss garden on the continent, growing moss — and keeping it from growing — takes work. Mr. Braid said he had noticed in recent years that the winter frost window had narrowed, and that the moss on rocks in the Japanese garden area had expanded in response. The problem is that the rocks are not supposed to be completely covered.

“You have to find that balance of just the right amount moss on there,” he said.

Mr. Braid, who has been at the reserve for 26 years, has cared for the Japanese garden for 15. Last year the moss garden was added to his duties. He spends his days weeding wetlands, pulling overgrown huckleberry bushes, planting an alder or hemlock tree, always seeking a balance of light and moisture, for the moss.

“It’s peaking right now,” Mr. Braid said.

Seattle has a longtime opinion columnist, Knute Berger, whose nickname is Mossback. He often writes about preserving the built environment, of finding a balance between making way for the future and respecting decay.

Asked about moss, Mr. Berger said, “I’m all for letting it grow.”

Mr. Berger, who does most of his work here for Crosscut, an online journal, pointed out how wealthy the city had become over the past few decades, how new people with new money sometimes tore down little old houses — sometimes houses that are covered with moss — and built big new ones in their places.

“There’s something about the moss image to me that is kind of the democratizing aspect of nature,” Mr. Berger said. “You might have a lot of money and you can fend most of it off, but you’re still going to have some moss on your roof.”

Source:http://www.nytimes.com/2011/04/20/us/20moss.html?_r=1&partner=rss&emc=rss