Eugene residents striving to be model environmental citizens — but still clinging to a traditional yard — can stop apologizing for their lawns.
Those expanses of green can actually collect and hold carbon and in so doing help slow climate change, said Morgan Peach, environmental studies researcher at the University of Oregon who is presenting his theories Wednesday at the third annual Climate Change Research Symposium on campus.
“They are, in many cases, enlarging the soil carbon pool,” Peach said. “It’s basically taking carbon dioxide out of the atmosphere. You have these photosynthetic grasses and they’re pulling the carbon dioxide out of the atmosphere and ushering it into the soil.”
So, can you stop feeling guilty about your lawn now?
“Yeah, you certainly can,” Peach said.
Peach is part of the daylong, campuswide symposium that will brings the arts, law, humanities, natural sciences and social sciences to bear on the subject of climate change.
Climate change is a prime topic on the UO campus of late. Students vote this week on whether the UO Foundation should divest its holdings in fossil-fuel related stocks. The foundation tends the university’s endowment and other donations. The vote is advisory only and the weeklong balloting ends at 4 p.m. Friday.
The UO was featured recently in a national story about teaching climate change — as a certainty — to students through literature, films, poetry, photography, essays and a new type of climate fiction called “cli-fi,” The New York Times reported.
A group of 80 faculty members and graduate students make up the university’s Oregon Climate Change Research Group.
Members meet monthly to increase understanding how academia approaches climate change, to promote research across disciplines — and, this week, to address the promises and pitfalls of teaching climate change.
“This stuff is tricky and I want to be very careful,” said Ron Mitchell, organizer and political science professor. “I want to be inclusive. Opinions and values and facts are all part of it.”
The process of education helps students distinguish between facts, values and viewpoints with regard to climate change.
Some parts are unresolvable.
Some people, for example, care more about environmental protection while others care more about economic growth, Mitchell said.
“De gustibus non est disputandum,” he said, then translated: “In matters of taste there can be no argument. You like economic growth; I like environmental protection. Who’s to say who is right? There’s no right. You just disagree with me. You like vanilla; I like strawberry.”
Differences in viewpoint can be extreme, he said.
“There are a lot of people in Africa who don’t want to worry about climate change because they would like to spend that money on (obtaining) a life expectancy greater than 50 years old, which is the life expectancy in Africa,” he said.
Who ultimately decides?
“That’s what democracy, small “d,” is about,” Mitchell said.
Sometimes the facts are unexpected, such as what Peach found in his yearlong study on Eugene lawns. The graduate student used ecosystem ecology, soil science and biogeochemistry to probe his theories about grass.
He knocked on 100 doors to find samples of immaculately kept lawns and lackadaisically kept lawns. He collected core samples 3.5 feet deep and analyzed them.
Peach found: “Here in Eugene-Springfield and the south Willamette Valley we have some of the finest soils in the country,” he said. “These residences have been built over historic prairie, so basically bread-basket-of-America soils, really productive, nicely structured rich, fertile soils.”
Those soils produce happy grasses that help remove carbon dioxide from the atmosphere.
The carbon “is pulled out of the atmosphere by stoma, the little mouths of grass leaves,” Peach said. “It’s then transformed into tissues of the grasses — the blades or root systems.
When the plants die, the tissues (with the carbon) are consumed by protozoa or nematodes, tiny even unicellular creatures that live in soils.
“This is happening right outside your front door and human beings are participating without even noticing (when) taking care of their lawns,” Peach said.
But what about the native plant enthusiasts who in recent years have ripped up their lawns and put in drought-resistant greenery and “brownery”?
Peach counts lawns as part of the diversity that brings reliance to the landscape.
“We should work toward managing and designing an urban landscape that has a mosaic of habitat types, like patches on a quilt for example. The managed lawn is just one patch among those many habitat types,” he said.
Peach’s study, however, had one significant result, he said. The more lackadaisically kept lawns had a lower carbon dioxide profile. Mowing, irrigating, fertilizing and spreading herbicide produced a lawn that held a comparatively high level of carbon dioxide, he said.
“Keep in mind the drawbacks of management,” he said. “If you are sequestering carbon in your lawn, but you’re out there mowing it every week and applying fertilizers with nitrogen that are leaching out into our local water system, maybe you want to think twice about the degree to which you are helping,” he said.
Really, he said, among lawns, an embarrassingly shaggy one is the best of all for the environment. “You can feel good about having a lawn out front, tending to it every so often — just as you please, really — and you’re doing a service to your urban ecosystem community,” he said.