Quaking Bogs

Quaking Bogs

A quaking bog forms in Provincetown (.jpg - 80k)

Quaking bogs are wetlands that have formed across the surface of shallow ponds. These ponds are characterized by slow groundwater flow, which causes the pond water to be acidic and low in dissolved oxygen (DO). The roots and rhizomes of invading wetland plants form floating mats across the pond, which creates an unstable, "quaking" surface. Over time, leaves, stems and other organic matter may accumulate below the mat and stabilize it. Nutrients are slowly released into the bog by bacterial decomposition at the surface.

Depending on the availability of nutrients, degree of soil saturation, water pH and DO level in a given bog, the site may evolve into a marsh or swamp. Quaking bogs support rare bog plants, such as dragon's mouth orchid (Arethusa bulbosa), and few fruited sedge (Carex oligosperma).

The world's largest known quaking bog found on a barrier beach is in the Shank Painter Pond system in Provincetown. Bogs are threatened by land development, changes in water flow, and pollution from runoff.