Anthony Stewart hiked through a forest on Washington’s Olympic Peninsula and prepared to dig. …It’s relatively dry on the surface, but just underneath it, a layer of reddish soil, full of organic matter, gives way to gray-blue, claylike soil. These layers, formed over time as water flooded the area, are signs of a wetland. But like many forested wetlands in the Pacific Northwest, this area doesn’t appear on any state maps. In a study published in Nature Communications this past January, Stewart, a Ph.D. student at the U of Washington’s School of Environmental and Forest Sciences, reported the abundance of unmapped, carbon-rich wetlands in the Pacific Northwest’s forests. …Wetland ecosystems are stunningly effective at soaking up carbon from the atmosphere. Despite covering only less than 10% of the world’s land surface, they contain roughly 20% to 30% of the carbon stored in the soil. [to access the full story, a subscription to The Atlantic is required]