Grasses and reeds are a special type of wetland in which plants form a mat that extends over the water like a floating shelf. As the plants die, the shelf thickens. The dead plants pushed below the water decay very slowly, due to lack of oxygen and high acidity. The mat eventually extends down to the lake bed, and the mat closes the open water on the lake. It is the floating mat which gives the sensation of a “quaking” bog. But please don’t try it! The plants which make up the floating mat are fragile – you can break through, which is dangerous to you and the bog! Tales of heavy equipment, cars, horses, and people sinking out of sight in bogs are legendary. Many of them are true. Bog plants include the carnivorous pitcher plant, sundew, poison sumac and dwarf birch. American Indians used to burn bogs periodically to spur growth of cranberries and blueberries.