Mount Calvert (18PR6) is located at the confluence of the Western Branch and the Patuxent River in eastern Prince George’s County. The site is significant for the diverse historic and prehistoric resources located on the property. Mount Calvert is the site of Charles Town (1696-1721), the first county seat of Prince George’s County, and was also a Federal Period plantation. A 1780s house still stands on the property. The site also contains multi-component prehistoric occupations spanning the Early Archaic through Late Woodland periods.

Archaeological Investigations

Between the summer of 1998 and the spring of 2000, the Maryland National Capital Park and Planning Commission (M-NCPPC) completed Phase I and II testing of select portions of the Mount Calvert site.

Phase I investigations involved historical background research and archaeological testing. Two areas of the site were investigated, one using a systematic pattern of 228 shovel test pits at 25' intervals, the other through a controlled surface collection. Approximately 7½ acres of the Mount Calvert property were surveyed. Distinct concentrations of late 17th- through mid-19th-century artifacts were identified from the surface collection data. Early Archaic through Late Woodland period prehistoric components were also identified. Shovel testing revealed two colonial period sites, one early 20th-century site, and Early Archaic through Late Woodland period prehistoric components.

Phase II testing involved five large excavation blocks comprising 83 5'x5' units. Archaeological investigations identified two colonial period sites associated with Charles Town and artifact deposits and features associated with a 20th-century tenant farm house. A total of over 34,000 artifacts were recovered from Phase I and II testing efforts.

Archeobotanical Studies

Phase II investigations included archeobotanical research which was conducted by Justine McKnight. Twelve samples of cultural sediment were retained from four discrete historic features encountered during the summer and fall of 1998 and October 2000. The features sampled included contexts probably associated with borrow pits, cellars, post holes, and a paling fence, most dating to the early 18th century.

Samples were processed using a Flot-tech flotation system equipped with 0.325 mm fine fraction and 1.0 mm coarse fraction screens. Processing of 46 liters of feature fill yielded 63.77 grams of carbonized plant macro-remains (an average of 1.39 grams per liter). Sample matrices were consistently composed of fine, medium, and coarse-grained alluvial sands and gravels, crushed brick or shell, abundant faunal remains, architectural debris, and a variety of other historic artifacts.

Wood charcoal was present in 100% of the flotation samples analyzed. A total of 6,638 carbonized wood fragments (> or = 2mm in diameter) weighing 63.23 grams were recovered. Of these, 187 fragments (a maximum of 20 fragments per sample) were randomly selected for identification. Identified taxa include (in order of abundance) white oak, hickory, red oak, unspecified oak, sycamore, pine, ash, and American chestnut, as well as deciduous, ring porous, and unidentifiable taxa. Nutshell was recovered from four of the twelve samples analyzed. Six fragments of nutshell weighing 0.05 grams were recovered. Hickory (three fragments), black walnut (two fragments), and walnut family (one fragment) shells were identified. Cultivated plant remains were restricted to a single flotation sample from Feature 71 (a borrow pit associated with late 17th- to early 18th-century post-in-ground structure which was possibly used as a cellar). A maize cupule fragment and a maize kernel fragment were identified. These two specimens weighed a scant 0.01 grams. Miscellaneous plant remains recovered from the site flotation samples include 24 fragments of amorphous carbon and one piece of unidentifiable starchy plant tissue (perhaps the burned remains of a tuber or fruit). Non-carbonized seeds were present in 75% of the samples analyzed, occurring in all of the features sampled from the site. These unburned seeds are considered modern intrusions into archaeological contexts. The archeobotanical report includes a careful discussion of recovered remains by feature.

The processing of feature fill from the Mount Calvert site yielded an interesting assemblage of archeobotanical remains which provide insight into plant use and landscape conditions on the western shore of the Patuxent River during the late 17th and early 18th centuries. The array of native wood species recovered reveals forest elements in the local landscape, and documents the selection of valuable building materials and high-caloric fuel woods and the use of mast-bearing species for stock forage or human consumption. The mixed wood taxa within the sampled features suggests the disposal of charcoal from cooking and/or heating fires, or perhaps (in the case of Feature 71) evidence of a building fire. Agricultural products were extremely scant within the assemblage, being confined to two specimens of corn identified within a single feature level (the deepest layer of Feature 71).

The features sampled for plant remains at the Mount Calvert site can be classified as largely architectural (house cellars, post features, and fences), which provide an opportunity to examine the recovered wood assemblage as building material. All species identified, especially the locally abundant white oak species, had important application in colonial architecture. Recovered comestibles reveal a reliance on agricultural products (corn), and the use of native nut crops. The scarcity of food-plant remains and the paucity of small grains and tobacco from the assemblage, however, are inconsistent with our understanding of 17th- and 18th-century plantation production and subsistence. The absence of data in support of these colonial staples at Mount Calvert should be regarded as a product of sampling bias rather than an accurate measure of their role in site economy.


Lucas, Michael, Donald Creveling, Erin Donovan, Michelle Niedzwiadek, Sara Rivers, and Matt Cochran
2001 "att Pig Pointe upon Mount Colverte" Phase I and Phase II archaeological testing of Mount Calvert (18PR6). Vol. 2. Maryland-National Capital Park and Planning Commission, Natural and Historical Resources Division Archaeology Program.
McKnight, Justine
2000 Results of Analysis: Flotation-recovered Botanical Remains from Mount Calvert (18PR6). Report submitted to National Capital Park and Planning Commission, Natural and Historical Resources Division Archaeology Program.

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