Sphagnum Bogs

Sphagnum Bogs

Sphagnum bog, West Falmouth (63k - jpg)

Sphagnum Bogs are rare wetlands that formed in wet depressions and have thick sphagnum mats and deep peat layers that are permeated by stagnant, acidic and mostly anoxic waters. The dominant plants of these bogs are herbaceous, low shrubs such as cranberry (Vaccinium macrocarpon) and leatherleaf (Chamaedaphne calyculata), as opposed to marshes and swamps, which are dominated by grasses and trees, respectively. The water quality inhibits decay, so fallen trees, pollen, or other organic material may remain preserved beneath the surface of the bog for thousands of years. Nutrients are locked up in the undecayed material, so growth conditions in the bog are nutrient-poor, and the bog plants are adapted accordingly.

The insectivorous pitcher plant (Sarracenia purpurea), and sundew (Drosera spp.), which obtain nutrients by trapping and digesting insects, are found in Cape Cod's sphagnum bogs. Some plants, such as dragon's mouth orchid (Arethusa bulbosa), and few fruited sedge (Carex oligosperma), are rare because they grow mainly in rare sphagnum bogs. Bogs are threatened by land development, changes in water flow, and pollution from runoff.