Baltimore Ecosystem Study Permanent Plot Vegetation Sampling Data for Baltimore Long Term Ecological Research Network (LTER)

The Baltimore Ecosystem Study for Permanent Plot Vegetation Sampling
is part of the Baltimore Ecosystem Study (BES) project.

Permanent plots are a powerful tool for understanding systems over the
long term because of the rigorous quantification of patterns in a
spatially refined way and because of the comparability of numerous
variables measured in the same place. In 1998, 7 plots were surveyed
into 3 forests in the study region of the Baltimore Ecosystem Study
(BES): Oregon Ridge Park (4 plots), Hillsdale Park (1 plot), and
Leakin Park (2 plots). Plots were surveyed in to correct for slope and
to achieve an accuracy of plot side length to within 0.5 cm. Plots are
1600 m2 with the exception of the Hillsdale plot which is 900 m2. The
Hillsdale plot is smaller to fit within the confines of the forest
patch. Sites were selected 1) to represent urban and non-urban
forests, 2) away from obvious habitat boundaries or edges, 3) with
consistent drainage lines within the plot, and 4) with at least 80 %
continuous tree canopy. All vegetation layers were sampled in order to
characterize the structure and composition of the plant community. A
variety of sampling methods were used for the different layers but all
layers were quantified with a high level of detail to minimize
variation and to best characterize the plot.

Plots were grided into 16, 10 x 10 m areas, or 9 in the case of
Hillsdale. Within each area, all trees were sampled and the height of
the tallest tree measured. The 10 x 10 m areas were divided into 4, 5
x 5 m subplots which are labeled in the data files as a1-4, b1-4, c1-4
and d1-4.. One of the 4 subplots was randomly selected for the
sampling of the other vegetation layers. All saplings in the subplot
were sampled and the tallest sapling measured. The cover of vines and
shrubs was quantified along two of the subplot boundaries and recorded
as cm of cover/m of transect. Finally, in each subplot, two quadrats
of 0.5 x 1.0 m were established at right angles to each other and the
percent cover of all species, percent cover of physical material, the
number of tree seedlings, and the number of tree seedlings with browse
damage were recorded. Quadrats are labeled 1 or 2.

The Baltimore Ecosystem Study (BES) aims to understand metropolitan
Baltimore as an ecological system. The program brings together
researchers from the biological, physical, and social sciences to
collect new data and synthesize existing information on how both the
built and wild ecosystems of Baltimore work. As a part of the National
Science Foundation's Long-Term Ecological Research Network, BES trys
to understand how Baltimore's ecosystems change over long time
periods. The ecological knowledge helps support educational
and community-based activities, and interactions between the project
and the Baltimore community are imporant components of our
project. Such an integrative project includes many disciplines and
many research and educational institutions, both in Baltimore and
beyond.

This information was obtained in part from the BES Home page at
http://www.ecostudies.org/bes/.

BES is part of the Long Term Ecological Research Network accessible at
www.lternet.edu. Data are one of the most valuable products of the
LTER program. The goal of the Network is to provide fast, effective,
and open access to LTER data. Over 2000 ecological datasets are part
of a network-wide information system designed to facilitate data
exchange and integration to meet the needs of ecological scientists.