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
12
m
Shrub Height
5
m
Field Height
5
m
Tree Cover
40
%
Shrub Cover
50
%
Field Cover
12
%
Nonvascular Cover
50
%
Misc Fields:
Observation Narrative
Plot location: upper portion of exposed quartzite cliffs at White Rock, 250 m NW of the summit of Signal Mountain. Not permanently marked. Rock types present: massive quartzite outcrops and boulders. Microtopography is irregular, craggy, and bouldery.
Because of practical constraints, a narrow plot configuration (13.33 X 30 m) was used to sample this very steep quartzite exposure, which supports a stunted (<15 m tall), floristically depauperate Pinus rigida-dominated woodland. A few Pinus pungens also occur on these cliffs, but are located outside the plot. Growing conditions are extremely stressful here, with plants rooted in crevices and shallow accumulations of acidic, infertile soil. Patches of ericaceous shrubs (Kalmia latifolia, Gaylussacia baccata, and Vaccinium spp.) dominate the shrub and herb layers where they can gain a foothold. The numerous, exposed rock surfaces support large colonies of umbilicate and foliose lichens, particularly Lasallia pensylvanica and Dimelaena oreina.
Soil Nutrient Status: low.
No profile development; soil limited to organic-rich silt and sand accumulations on ledges and in crevices.
Physical Analysis: 5% clay, 43% silt, 52% sand.
