bogmat

A bogmat begins with submerged plants growing on a lake’s floor, then moves to a second stage of development, the growth of plants whose roots stay on the bottom but whose leaves float—water lilies, for example. The proliferation of plant roots that thrive in water eventually creates a fragile surface on the water, a thin mat of vegetation over the lake. In the fourth stage of bogmat development, the sedge or fen stage, this fragile mat thickens and the assemblage of plants grows more limited in variety. As seasons pass, shrubs (cranberry, poison sumac) become part of the mat. Leaf forms change. Thick, hoary leaves suggest a lack of water, even when water is abundantly present. Finally, the surface becomes thick and oily, yet still unstable enough to swallow up a team of horses. Bogmats at this point are considered “physically wet but physiologically dry.” These conditions cause a nutrient deficiency for plants, due to lack of drainage. The result: poor aeration, diminished nitrogen, increased acidity. This brings about the last stage of bogmat formation: the growth of tamarack trees, which provide shade, a new element, and of hummocks with shallow root systems. The mat thickens, the forest grows more dense, and the earth becomes, once again, firm beneath the feet. A witness to what Emily Dickinson called “truth’s superb surprise.”

Elizabeth Cox