Research ProjectSpatial Dimensions of Forest Dynamics

Spatial Dimensions of Forest Dynamics

Map of ForestGEO plot

Stem map of the 16 hectare ForestGEO plot color coded by species


The Forest Dynamics Plot at the Smithsonian Environmental Research Center (SERC) is a study of the long-term spatial dynamics of woody forest plants.  In the 16 ha plot all woody plants with a diameter at breast height (DBH) equal to or greater than 1.0 cm are mapped to location, identified to species, measured for DBH and assessed for condition.  The plot was established in the fall of 2007 and the first census was completed in August 2011.   The plot is a subset of a much larger study area initiated in 1987.  This project follows the protocols of the Smithsonian Institution Global Earth Observatory (, a network of similar efforts.  

Studies on the SERC plot are primarily focused on tree demography and carbon dynamics in a human-dominated landscape.  The plot has 3 small buildings (0.97 % of the area) and some roads, paved and unpaved (3.92 % of the area), for a total forest area of 15.36 hectares.  Such evidence of anthropogenic activities is typical of this region, which has long been impacted by humans, particularly by European colonists since the middle of the 1600’s.  The majority central portion of the plot was most likely a pasture until abandonment in the late 1800’s.  To the southeast and northwest edges of the central core are younger stands, both of which were fields abandoned in the 1930’s.  These two stand age classes are the dominant ones in the region. 

The plot is located about 10 km SW of Annapolis, Maryland on the western shore of the Chesapeake Bay.  It is in the coastal plain physiographic province and has a substrate of deep sediments.  The geographic boundaries of the square plot are 38.8873020 to 38.8910041° N (latitude) and 76.5618021 to 76.5571295° W (longitude).   The site sits close to sea level (0.2-12.0 m elevation range) and is mostly flat (slopes average 8.4 ± 7.2°).  However, a stream and its floodplain curve through the plot from the NE to SW.   Precipitation, mostly rain, averages 1090 ± 172 mm annually; the mean temperature is 12.8 ± 0.7 ° C (NOAA regional climatology 1895-2010). 

The forest is diverse (78 species) and includes two distinct associations: the upland portion is in the ‘tulip poplar’ forest type and the wet areas are of the ‘river birch-sycamore’ group.  The shrub spicebush (Lindera benzoin) numerically dominates, primarily in the lower elevations.  Biomass is dominated by tulip poplar (Liriodendron tulipifera), sweetgum (Liquidambar styraciflua) and American beech (Fagus grandifolia).  It has a total of 33426 stems (2177 ha-1) of which 7.07% are dead.  Mean basal area is 40.8 m2 ha-1 and above-ground biomass 381 Mg ha-1.

For further information on the study and enquires about collaboration, contact Geoffrey Parker (