This is an EarthCache and there is no physical container to find! To successfully log this EarthCache, first read the earth science lesson and questions below, visit the Suitland Bog Natural Area, and then send us your answers.
Please park at the Suitland Community Center and walk to the trailhead. See the parking and trailhead waypoints in this cache listing.
This is a protected area that contains several endangered plant species. Please stay on the marked paths, and do not pick or harvest any plants.
Welcome to the Suitland Bog Natural Area!
This bog is a unique wetland botanically called a fen (a wetland with alkaline, neutral, or only slightly acidic peaty soil) and is a rare habitat within the Washington Metropolitan Area. It hosts a variety of carnivorous plants as well as many plants that are on the Maryland Natural Heritage Program’s “Rare, Threatened, and Endangered Plants of Maryland” list.
Geologically, this area falls within the coastal plain section of the upper Anacostia (all of the watershed in Prince George’s County and some areas along the fall line in Montgomery County) which is underlain by vast deposits of sand, gravel, silt, and clay of the Lower Cretaceous Potomac Group (Patuxent Formation). Broadly, these deposits overlie crystalline bedrock and are highly variable throughout the formation, ranging from small to massive, heterogeneous lenses to interbedded layers. The thickness of the unit varies from thin layers in places along the "Fall Line" to several thousand feet off the eastern shore, with an average thickness of 500 feet. Tertiary gravels of Miocene and Pliocene ages cap the highest elevations of the fall line and coastal plain. Quaternary sand and gravel deposits and alluvium outcrop at lower elevations along streams and incised lowland valleys. As you’ll read later on, these gravel deposits are a key component to the creation of fens like the Suitland Bog.
From the October 2002 issue of Audubon Naturalist:
“Magnolia Bogs have long been regarded as one of the most interesting natural features in the Washington, D.C. area. W. L. McAtee, a Washington area naturalist who first defined these bogs in 1918, termed them "Magnolia Bogs" for the unique assemblage of sweetbay magnolia (Magnolia virginiana), Sphagnum moss, and other bog flora. Occasionally they are referred to as "McAteean Bogs," after McAtee, or "Seepage Bogs." These bogs usually form on hillsides or slopes where a spring or seep flows from an upland gravel and sand aquifer over a thick, impervious layer of underlying clay which prevents the downward infiltration of water. This seepage flow and the highly acidic, gravelly soils create optimal conditions for the formation of bogs.
The term "bog" as applied here, although technically a misnomer, has traditionally been used by people in general, including botanists, to describe acidic, sphagnous wetlands that strongly resemble bogs. Magnolia Bogs are actually acidic, fen-like seeps uniquely associated with high elevation gravel terraces of the inner Coastal Plain near the Fall Line, which divides the Coastal Plain and Piedmont physiographic provinces in the mid-Atlantic region. Their distribution generally follows the Fall Line in a narrow east-west band from the Laurel area, at the northern extent of their range in Prince George's County, Maryland, to their southern extent near Fredericksburg, Virginia.
Throughout their range, they were never common or very large, usually occupying an area an acre or less in size. Nevertheless, they are vitally important resources both for the pure, naturally filtered waters which flow continuously from them — even in drought periods — and the relic populations of ancient northward and westward migrations of often rare Coastal Plain flora, which have persisted in small communities well inland and fairly close to the Piedmont.”
Questions you must answer and send before logging this EarthCache:
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What combination of geological conditions cause the formation of this kind of bog?
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What kind of soil creates the optimal condition for forming this kind of bog?
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What is the name of the geological division that separates the Coastal Plan and the Piedmont physiographic provinces, and is typically where these kinds of bogs are found?
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Within the bog area itself, from the safety of the boardwalk, how would you visually describe the soil here and how is it different from the soil at the interpretive sign?
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Please post a picture of yourself (face not required) or a personal item with one of the interpretive signs: there's one at the trail entrance coming from the Community Center, or there's one at this EarthCache's coordinates.
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