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
1000
m²
Plot Quality Fields:
Plot Validation Level
(2) classification plot: sufficient for inclusion in a classification revision
Overall Plot Vegetation Fields:
Tree Height
31
m
Shrub Height
6
m
Field Height
5
m
Tree Cover
70
%
Shrub Cover
70
%
Field Cover
45
%
Nonvascular Cover
0.5
%
Misc Fields:
Observation Narrative
A permanent 1000 sq. meter releve plot was installed in this old-age stand (see original plot form for diagram of rebar and tree tag placement). This is one of several stands in the Cumberland State Forest aged by DOF at 242 years, and forms the Turkey Ridge Natural Area, which was given permanent protection in the 1970's as an outstanding example of a xerophytic upland oak-hickory forest growing on hardpan soil. The site is probably underlain by mafic rocks which produce montmorillonite soils with abundant clay minerals. Drainage is slow due to an impermeable subsoil, and the soil alternates bewteen waterlogged during rainy periods and extremely hard-baked during dry periods. The overall stand is co-dominated by white oak, post oak, and pignut hickory, with canopy associates of white ash, shagbark hickory, northern red oak, and mockernut hickory. Winged elm, eastern red-cedar, and recruitment of the canopy species dominate the understory, while black needlegrass (Piptochaetium avenaceum) dominates the herb layer. The plot was placed on the eastern side of an old road which bisects the natural area along a ridge crest. Post oak is under-represented, and hickories somewhat over-represented in this area (see plot CUSF005, which was sampled on the western side of the road, for an example of the post oak-dominated variant). Although not large by absolute standards, many of the dominate overstory trees are no doubt quite old and have grown slowly in the rather stressful edaphic environment. Likely historical disturbances in this stand include grazing and high-grading, the latter indicated by a scattering of very old pine stumps and lightwood.
