Proceedings of the Sixty-first Annual Meeting of the Northeastern ...

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A PRELIMINARY STUDY OF THE NON-NATIVE VASCULAR FLORA OF THREE
COASTAL DELAWARE STATE PARKS. R. Stalter, E. Lamont, G. Grigoryan, and
N. Faqeer, St. John’s University, NY.
ABSTRACT
The objective of the present preliminary study was to document non-native
vascular flora at the three coastal Delaware State Parks: Cape Henlopen, Delaware
Seashore and Fenwick Island. Monthly trips were made to the parks during the
growing season of 2006 beginning in April, terminating in October. Over 450
specimens were collected. These were mounted on herbarium paper and will
eventually be housed in the Batson Herbarium, University of South Carolina. The
preliminary list of non-native vascular flora includes 73 species, 22% of the three
parks flora. Three hundred thirty five vascular plant species have been identified as
of October 15, 2006. Families with the greatest number of non-native vascular plant
species were the Poaceae and Asteraceae with 13 and 11 species respectively.
Plant families composed exclusively on non-native species were the
Commelinaceae, Elaeagnaceae, Liliaceae, Molluginaceae and Oleaceae.
INTRODUCTION
Cape Henlopen State Park (CHSP) Delaware Seashore State Park (DSSP)
and Fenwick Island State Park (FISP) extend from mid coastal Delaware south
along the Delaware coast to the Delaware Maryland state line. Cape Henlopen
State Park is separated from the mainland by the Lewes and Rehoboth Canal on its
western border. Rehoboth Bay separates Delaware Seashore State Park from the
mainland while an Assawomen Bay on the west separates Fenwick Island State
Park from the mainland.
Delaware Seashore and Fenwick Island state parks are narrow spits of land
approximately 300 meters wide. From the western bay boundary east to Route 1
the topography is relatively flat with an elevation of 1 to 2 meters above mean sea
level. East of Route 1, beach dunes range from approximately 5 to 10 meters in
height. Inland island central dune fields at Cape Henlopen range in height from 9 m
to 15 m in the central portion of the park. Route 1 dissects Delaware Seashore and
Fenwick Island; disturbance i.e., mowing and roadside maintenance provides
excellent habitat for aggressive weedy alien species.
PLANT COMMUNITIES
Six naturally occurring plant communities occur at the three state parks.
These include the dune-grass dominated primary dune community, the pine oak
community on stable old dunes, a transitional shrub community, an extensive-salt
marsh community, an extensive brackish marsh community, and a sedge-forb
dominated community on moist interdunal swales. Most non-native species occupy
disturbed sites including maintained roadsides and gardens around habitations.
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