Fire in the Swamp

Mineral soil in white-cedar sites can be covered by some 20 feet of debris collected over many decades in the absence of drought-induced fire. Then fire can play havoc with Atlantic white-cedar, readily destroying forests of all ages. When fires occur, they may crown, moving rapidly in the tops of trees to kill stems some distance away in isolated ponds. Ground fires might occur simultaneously, once the peat is ignited. These fires burn the fibrous, well-oxygenated organic matter under the surface of the land, even during the snows of winter, until the soil is again saturated by rainwater.

A second fire following close after a first, before there is time for a new stand to replenish the supply of seed stored in the duff, eliminates this forest cover type. If the fire consumes other woody growth along with the swamp-loving conifer, ecological retrogression to a quaking bog, or even to open water, could occur.

If protected from fire to an old age, the bog climax forest that follows will likely be an assortment of wet-site deciduous species. The amount of charred peat on the surface of the ground and the quantity of charcoal in the upper layers of peat suggest how long a time has elapsed since a site last burned.

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