Editor's note: a previous version of this story said that 52 acres were added to Killin Wetlands Nature Park. The new purchase is part of the natural area that is connected to the park.
Metro added 52 acres to Killin Wetlands Natural Area in Washington County, between Forest Grove and Highway 26. The purchase means more than 640 acres, one square mile, of connected habitat is being conserved, including two rare habitats that support dozens of plant and animal species. Killin Wetlands Nature Park offers visitors a chance to see the marsh.
The $465,000 purchase was possible because of voters investing in nature by passing the 2019 parks and nature bond measure. The $475 million bond measure includes $155 million to protect and restore land, with a focus on protecting clean water and strengthening fish and wildlife habitat, especially for salmon, trout, steelhead and lamprey.
Killin Wetlands is one of the few remaining peat wetlands in the region. It is also home to one of the few known natural populations of Geyer willow in the Willamette Valley. Seeds from Killin have been used to reintroduce the willows to other sites in the region.
Peat soil is made when the leaves from pond lilies, willows and other wetland plants sink to the wetland floor and then partially decompose. Think of it like wetland compost: it’s dark and rich, light and spongy. This process draws carbon out of the atmosphere and stores, or sequesters, it in the wetland.
Forests are the most celebrated carbon sequesters, but wetlands store even more carbon in their peaty bottoms, and that carbon is much less vulnerable to being released back into the atmosphere during a wildfire. The new purchase adds 35 acres to the wetland.
“The additional protection of peat wetland acres add to the huge bank of land out there that. … [It] acts as one of the planet’s most efficient carbon sinks, capturing carbon in plant material that is steadily buried in the soil,” said Curt Zonick, a former Metro scientist who managed restoration at Killin for more than two decades.
Peat soil makes excellent farmland. When European Americans colonized the region in the mid-1800s, many wetlands, including Killin, were drained and turned into farms. The peat dried out and collapsed in the process, lowering the land’s elevation. The wetland had already begun to refill with water when Metro acquired the first tracts of land. Beavers have made dams and lodges that have held more water in the wetlands.
The peat’s lower elevation created a habitat more like a lake, but as leaves and stems and other plant matter build back the peat, the habitat should be restored.
Samples have shown that peat has developed for the past 25 years, and scientists studying the site expect it will take another 100 to completely remake the peat. Each year’s layer will store carbon pulled out of the atmosphere.
The new purchase adds to the wetland, and includes land at a bit higher elevation that will be restored to oak savanna. These open spaces, dotted with Oregon white oaks, support 140 animal species and approximately 375 plant species. Oak savanna was one of the most common habitat type on the Willamette Valley floor before colonization.
The upland juts out into the wetlands, creating a peninsula that Zonick expects will attract western pond turtles, a threatened species that has thrived in the wetland since restoration work began. “It’s a great place for turtles to lumber out of the swamp and bury eggs that will stay dry until hatched,” Zonick said.
Restoration work at Killin is funded by both the 2019 parks and nature bond measure and a local option levy voters approved in 2012 and renewed in 2016.