Mired in Peatlands

Many of us are familiar with the park's dominant plant communities: montane, sub-alpine, alpine and riparian. But these broad-brush classifications miss the subtleties of smaller scale communities such as peatlands.

Peat is a soil that contains a high proportion of dead organic matter, mainly plants. Peat soils form in conditions where the soil is waterlogged and the lack of oxygen and/or cold temperatures limit decomposition. Peatlands are found in the park in scattered locations where seeps, springs, high groundwater, abandoned beaver colonies, or impenetrable clay layers result in very wet soils for much of the growing season, but not so wet that plants can't grow.

The term peat is derived from the Welsh word perth referring to a piece of peat soil that was cut for fuel. Ecologists use several specific terms to distinguish between types of peatlands. (The United Kingdom has a wide range of peatlands and hence a rich vocabulary for describing these communities.)

Fen - A peatland that receives water and nutrients from the soil, rock, and groundwater as well as from rain or snow. (From fenn, Old English for marsh.)

Bog - A peatland which receives water solely from rain or snow falling on its surface. (Akin to the Gaelic word for soft.)

Mire – A peatland where peat is currently forming and accumulating. (A Middle English word that is related to Old English mos and Old Norse myrr.)

Although not particularly famous (most of us avoid hiking in wet and soggy places,) peat communities do sustain unique assemblages of species and they are vulnerable to destruction. When peatlands dry out, they may decompose rapidly. Global climate change is certainly contributing to the destruction of peat soils around the world as localities become warmer and drier.

The Grand Ditch, a water diversion project that predates the establishment of the park, significantly limits the amount of water reaching peat communities below the ditch during the driest part of the summer. The park is investigating whether small amounts of ditch water, released to key locations, might assist in maintaining some peatlands. If so, perhaps water rights could be purchased and used to protect these lesser known, but biologically valuable, plant communities.