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
29
m
Shrub Height
6
m
Field Height
5
m
Tree Cover
75
%
Shrub Cover
45
%
Field Cover
5
%
Nonvascular Cover
12
%
Misc Fields:
Observation Narrative
Resample of 13-year old permanent plot. Corners are now monumented with rebar stakes painted light blue.
This plot has suffered muultiple disturbancs and undergone significant vegetational changes since the 2001 sampling. A large Quercus rubra and several smaller Quercus montana were wind-thrown, resulting in a very open (~35%) canopy with several gaps. Several understory Nyssa sylvatica died, reducing the cover of that species from >10% in 2001 to <2%. Some die-back of Kalmia latifolia branches was noted, even though the density of measureable stems increased slightly. Vaccinium pallidum, which covered >5% of the plot in 2001, now covers <1%, no doubt the victim of heavy deer browse. Finally, nine of the original 29 species recorded have disappeared altogether. However, 30 new species (not recorded in 2001) were documented in the 2014 sampling, including small Asimina triloba, many low-cover native forest herbs, and the potentially invasive exotics Microstegium vimineum, Ailanthus altissima, and Celastrus orbiculatus, contributing to a total species richness of 50 taxa. This is by far the highest species turnover recorded among the permanent Bull Run Mountain plots resampled in 2014. The fact that this stand is essentially an oak/heath forest (normally a species-poor vegetation type), makes this situation most unusual and worthy of close scrutiny in the future.
