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
6
m
Shrub Height
1.5
m
Field Height
8
m
Tree Cover
14
%
Shrub Cover
8
%
Field Cover
65
%
Misc Fields:
Observation Narrative
This Shenandoah Velley sinkhole pond had drawn down only recently on the survey date. It has several vegetation zones, including a north-side marginal zone of Woodwardia virginica and a small central zone containing a mat of Eleocharis acicularis and Glyceria acutiflora. The plot is located in the prevalent zone, occupying most of the south side of the pond. It captures several small pin oaks that occur near the margin and extends to near the pond center. Water marks on woody stems indicate a flooding depth of ca. 45 cm on the margin and 55cm toward the center. The vegetation is a mixed herbaceous stand with scattered buttonbush covering about 8% of the plot area. Abundances of individual herbs vary with stages in the draw-down cycle, with Eleocharis acicularis and Glyceria acutiflora generally attaining maturity first, followed by annuals and perennials such as Panicum verrucosum, Eleocharis melanocarpa, Panicum rigidulum var. rigidulum, and Helenium virginicum. Eleocharis acicularis was nearing maturity and huge numbers of Viola lanceolata and Panicum verrucosum seedlings were present on the survey date. This pond is noteworthy for having one of the larger populations of Helenium virginicum, but few bolted individuals of that species were present (many seedlings were present).
