blanket bog

:  a highly acidic peat bog that spreads out widely over the landscape and is found in cool climates with high levels of rainfall and humidity Blanket bogs form as the peat spreads out over the landscape like a blanket. — Rebecca Marsden, Geographical Magazine, September 1991 Called blanket bog for good reason, these boglands cover hundreds of soggy … square miles in northwest Mayo, which helps explain why the region is Ireland's least populous. — Megan Harlan, New York Times, 8 July 2001