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Vanderbilt Mansion

National Historic Site

New York

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photo of the mansion
Vanderbilt Mansion National Historic Site, New York

Topography, Soils, Vegetation, and Land Cover

Roosevelt-Vanderbilt national historic sites are in the Northern Appalachian Plateau and Uplands Ecoregion (Omernik 1987). This ecoregion is characterized by open high hills, tablelands with moderate to considerable relief, northern hardwoods (maple, birch, beech, hemlock), a mosaic of land use including cropland, pastureland, woodland and forest, and inceptisol soils (young soils with minimal horizon development). Dutchess County, the general area west of the Taconic State Parkway and north of Interstate 84, is characterized by numerous small hills ranging in height from 20 to 300 feet above the intervening valleys. Elevations range from 40 feet above mean sea level at the Hudson River to 900 feet. Slopes in excess of 15% occur along the Hudson River, especially at the Vanderbilt Mansion and Home of Franklin D. Roosevelt national historic sites.

Dutchess County soils are derived primarily from glacial till and outwash, organic matter, and lacustrine and alluvium sediments (Dutchess County Department of Planning 1985). Glacial till consists of unstratified, mixed deposits of clay, silt, sand and rock fragments deposited by glacial ice. Glacial outwash is material swept out, sorted and deposited beyond the ice front by streams of glacial meltwaters. These deposits are usually stratified and made up of sands and gravels. Organic matter such as decomposed plant and animal residue forms the basis of muck soils. Many of these soils are the direct result of glaciation, which by impeding drainage caused wetlands to form. Lacustrine sediments consist of very fine sands, silts and clays that have settled out of the still water of lakes. Alluvium sediments consist of material moved and redeposited by streams.

Major soil types at the Vanderbilt Mansion National Historic Site are Colonie fine sandy loam (hilly and steep phases) and Hoosic gravelly loam (Soil Conservation Service 1955). Crum Elbow Creek follows primarily through Colonie fine sandy loam. The majority of the physical development at this site is on the nearly level phase of Hoosic gravelly loam; the steep phase of Hoosic gravelly loam occurs below the physical development along the floodplain of the Hudson River. Smaller amounts of the following soils also occur: Staatsburg gravelly loam and NassauCossayuna gravelly loams. The latter occurs in the Bard Rock area and along the southwestern park boundary in the Hudson River floodplain.

At the Home of Franklin D. Roosevelt National Historic Site the major soil types include Hoosic gravelly loam, Colonie fine sandy loam, Steep ledgy land (Wassaic and Staatsburg soil materials), and Staatsburg gravelly loam (Soil Conservation Service 1955). Surface water within the Meriches Kill fluvial system flows over steep ledgy soils. The majority of the Hudson River floodplain is of this soil type. All physical development and landscaped areas are on Hoosic gravelly loam and Colonie fine sandy loam. Small areas of Rhinebeck silt loam (indicative of a former lake plain terrace) and tidal marsh, freshwater phase (north end of tidal cove), are also present.

Major soil types at the Eleanor Roosevelt National Historic Site include Hoosic gravelly loam and Saco silty clay loam (Soil Conservation Service 1955). The Fall Kill fluvial system flows through the latter. Minor soil types include Staatsburg gravelly loam, Hoosic gravelly sandy loam, and muck.

Soil permeability rates for the western half of Dutchess County, including Roosevelt-Vanderbilt national historic sites, are generally less than 0.63 inches per hour. This level severely limits the soil's suitability for septic tanks (Dutchess County Department of Planning 1985). However, in many of these areas septic systems have been functioning adequately for years. Local variations in soil or slope features and use of fill in creating septic fields have, in the past, enabled these septic systems to operate properly (Dutchess County Department of Planning 1985).

Upland vegetation at Roosevelt-Vanderbilt national historic sites is characterized by mixed oak forest, hemlock/mixed oak forest, and mixed species deciduous forest. On steep moist slopes with shallow soils, chestnut oak-eastern hemlock forest predominates. Lowland red maple forest occupies the moderately low elevations between the riparian zones of streams and the upland forested areas. Early successional ash/gray birch forest has colonized previously open areas at Eleanor Roosevelt National Historic Site.


Dutchess County consists of younger unconsolidated glacial and recently deposited materials overlying older consolidated bedrock material. There are five types of bedrock in Dutchess County; however, all three national historic sites overlie only one type - Austin Glen Graywacke and shale (Dutchess County Department of Planning 1985). This formation was deposited on an ancient, unstable continental shelf. It is a poorly sorted rock type that displays many of the features of a rapidly deposited sediment, including ripple marks and cross bedding. The formation consists of thin- to medium-bedded, coarse, gray sandstone or fine-grained conglomerate composed of firmly-cemented rounded fragments. Wells in this formation produce approximately 16 gallons per minute (gpm) of moderately hard water (Dutchess County Department of Planning 1985).

During the last glacial period (10 to 20 thousand years ago), Dutchess County was covered by ice (Dutchess County Department of Planning 1985). As the glaciers retreated, layers of glacial till were deposited over much of the bedrock. Glacial till consists of a heterogeneous mixture of poorly-sorted rock materials (clay, sand, pebble, and boulder), often having a high clay content. The western half of the Home of Franklin D. Roosevelt National Historic Site consists of glacial till. Eleanor Roosevelt National Historic Site has only a small portion of glacial till. Glacial till thickness over bedrock ranges from 0 to 20 feet on hilltops and from 20 to 40 feet on slopes. The high clay content of glacial till usually limits permeability; therefore, ground water recharge is slow with average recharge capacities estimated at 0.17 gpm per acre (Dutchess County Department of Planning 1985). Water in usable quantities can only be obtained from glacial till deposits using large diameter wells. Such wells, which are necessarily shallow, often go dry during periods of low precipitation. Recorded yields in glacial till deposits in Dutchess County average 22 gpm (Dutchess County Department of Planning 1985).

At Eleanor Roosevelt National Historic Site and Vanderbilt Mansion National Historic Site the bedrock is overlain by glacially-derived sand and gravel. These deposits range from layers of clean sand to layers of mixed sand and gravel, and are usually underlain by thinner layers of silt and clay. The sand and gravel mixture is the most productive water-bearing deposit in Dutchess County. Well production averages 136 gpm with an average recharge rate of 0.74 to 0.93 gpm per acre (Dutchess County Department of Planning 1985).

These aquifers are vulnerable to contamination. The same characteristics that enable aquifers to absorb, store, and yield large amounts of ground water allow them to absorb, store, and transmit pollutants. The Dutchess County Department of Planning (1985) stated that many cases of ground water pollution occurred in the years prior to and during its study.

Source National Park Service, Water Resources Division


Dutchess County Department of Planning. 1985. Natural Resources. Poughkeepsie , NY.

Omernik, J. 1987. Ecoregions of the conterminous United States . Annals of the Assoc. Am. Geographers 77(1):1 18-125.

Soil Conservation Service. 1955. Soil Survey, Dutchess County , New York . U.S. Department of Agriculture. Series 1939, No. 23.

park maps subheading

The General park map handed out at the visitor center is available on request from the park's webpage.

For information about topographic maps, geologic maps, and geologic data sets, please see the geologic maps page.

photo album subheading

A geology photo album has not been prepared for this park.

For information on other photo collections featuring National Park geology, please see the Image Sources page.

books, videos, cds subheading

Currently, we do not have a listing for a park-specific geoscience book. The park's geology may be described in regional or state geology texts.

Please visit the Geology Books and Media webpage for additional sources such as text books, theme books, CD ROMs, and technical reports.

Parks and Plates: The Geology of Our National Parks, Monuments & Seashores.
Lillie, Robert J., 2005.
W.W. Norton and Company.
ISBN 0-393-92407-6
9" x 10.75", paperback, 550 pages, full color throughout

The spectacular geology in our national parks provides the answers to many questions about the Earth. The answers can be appreciated through plate tectonics, an exciting way to understand the ongoing natural processes that sculpt our landscape. Parks and Plates is a visual and scientific voyage of discovery!

Ordering from your National Park Cooperative Associations' bookstores helps to support programs in the parks. Please visit the bookstore locator for park books and much more.

geologic research subheading


For information about permits that are required for conducting geologic research activities in National Parks, see the Permits Information page.

The NPS maintains a searchable data base of research needs that have been identified by parks.

A bibliography of geologic references is being prepared for each park through the Geologic Resources Evaluation Program (GRE). Please see the GRE website for more information and contacts.

selected links subheading

NPS Geology and Soils Partners

NRCS logoAssociation of American State Geologists
NRCS logoGeological Society of America
NRCS logoNatural Resource Conservation Service - Soils
USGS logo U.S. Geological Survey

teacher feature subheading

Currently, we do not have a listing for any park-specific geology education programs or activities.

General information about the park's education and intrepretive programs is available on the park's education webpage.

For resources and information on teaching geology using National Park examples, see the Students & Teachers pages.
updated on 01/04/2005  I   http://nature.nps.gov/geology/parks/vama/index.cfm   I  Email: Webmaster
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