releve Virginia Division of Natural Heritage, see http://www.dcr.virginia.gov/natural_heritage/documents/nh_plotform_instructions.pdf
Overall Taxon Cover Values are Automatically Calculated?
no
Stem Observation Area
400
m²
Plot Quality Fields:
Plot Validation Level
(2) classification plot: sufficient for inclusion in a classification revision
Overall Plot Vegetation Fields:
Tree Height
28
m
Shrub Height
5
m
Field Height
5
m
Tree Cover
80
%
Shrub Cover
70
%
Field Cover
65
%
Nonvascular Cover
4
%
Misc Fields:
Observation Narrative
Along with plots GFNP054 and GFNP055, this plot was sampled to explore the relationship between vegetation above Great Falls on the Virginia side of the Potomac River with enigmatic vegetation documented by Chris Lea at a similar topographic position on the Maryland side. The three plots capture a habitat and vegetation gradient, from the upstream end of an "island" formed by the river, an old canal, and Mine Run to the downstream end just above the falls. The topography in this area transitions from a well-drained floodplain to the bedrock terrace that develops as the river drops precipitously through the falls. The floodplain in this plot contains bedrock outcrops and its vegetation resembles that of the dry oak-hickory forest that occupies the terrace below the falls. The site was flood-scoured during late June or early July of 2006.
0 - 10 cm: yellow-brown stony silt loam
Composite sample collected from three locations.
Disturbance Data:
Disturbance Type
Disturbance Intensity
Disturbance Comment
unknown
Although exotics have significant cover in this plot, they are much worse in adjacent parts of the stand. The plot is adjacent to an old canal dug by George Washington to bypass the falls.