Peatlands at Neskowin Marsh

PROMO Intro Bog 512x219

Forested lagg, sphagnum bog or poor fen? Don't get mired in the detailsit's all peat-iful.


Wherever freshwater is allowed to pool up and stagnate across a relatively level area of land, you've got the makings for a mire. Sometimes it's in the poorly drained basin of a glacial lake; sometimes it's where a spring burbles up and spills over an impermeable layer of bedrock. Sometimes it occurs right on the coast, walled in by dunes and spritzed with ocean-spray. Mires can even form when old beaver ponds are cut off from their input, and thenceforth replenished only by rainwater.

In any case, the stilled water stagnates. Plant nutrients are used up and left unstocked. As wetland flora die in this almost static environment, they decay very slowly, forming a spongy, generally acidic, nutrient-poor soil known as peat. Over the course of thousands of years, as peat accumulates beneath the water's surface, the plant community changes. Those with floating leaves disappear, replaced by prostrate species that close in from the water's edge. Sphagnum mosses abound, as well as carnivorous oddballs such as sundew, pitcher plants and Venus flytraps. Open water gives way to rafts of this strange vegetation, fluid and thriving above the tannin-dark matrix of roots and saturated soil. Inch by peaty inch, the habitat is transformed from a productive wetland to the comparative dormancy of a peat-forming mire.

Mires are most commonly found at cooler, northerly latitudes with plenty of precipitation. Coastal Oregon was once rich in these so-called peatlands: As rain and salt spray pooled behind stable foredunes along the beach, wetlands were formed, leading eventually to all manner of marshes, bogs and fens. Today, many of these areas are gone, shaded out by the succession of shrubs and trees in the absence of fire, or drained for agriculture and pastureland, or otherwise filled in and developed. At Nestucca Bay NWR's Neskowin Marsh, a mere fragment of this fragile habitat remainsyet it constitutes the largest acid-forming peatland on the entire Oregon coast. At several millennia in the making, it's not peat-ering out anytime soon.