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
18
m
Shrub Height
2
m
Field Height
5
m
Tree Cover
25
%
Shrub Cover
10
%
Field Cover
90
%
Nonvascular Cover
25
%
Misc Fields:
Observation Narrative
At the base of Devils Backbone is an unusual acidic seepage swamp compositionally unlike any other documented in Virginia. This depression, which covers ca. 1500 sq. m, is full of standing water and early spring to a depth of perhaps 0.5 m or more in most years, but was entirely devoid of surface water at the time of sampling except for one small patch (10 sq. m?) near the southeast corner (outside plot). The hydrologic regime is uncertain, but the swamp appears to be fed by a small spring at the base of the adjacent slope. Also unclear is the extent to which the hydrology has been modified; the road running next to the swamp was built before 1950, when at least three families lived in the Elk Run valley. More recently Robert Ritchie has apparently reinforced the outer "rim" and deepened the inflow channel from the spring; consequently the swamp is now more reliably wet each winter. He has pondered removing or at least girdling the Acer rubrum in an effort to increase or prolong inundation; the hydrologic effects of such action are unknown. Some snags of Acer are already present. Other species observed outside the plot include Dulichium arundinaceum, Carex baileyi, Carex gynandra, and Glyceria striata. Rectangular plot design employed because fewer corners needed to be marked and thus disturbance to vegetation could be lessened. Values for surface substrate do not sum to unity because Sphagnum is often present at surface where there is no litter or other organic matter.
