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
31
m
Shrub Height
6
m
Field Height
1
m
Tree Cover
90
%
Shrub Cover
12
%
Field Cover
85
%
Nonvascular Cover
1
%
Misc Fields:
Observation Narrative
In the present-day landscape, this site presents a rare opportunity to study the dynamics of a Coastal Plain swamp forest that is occasionally impacted by fire. The floodplain of Antioch Swamp is located adjacent to an extensive area of sandhill woodland that is managed by prescribed fire. The plot is located in a transitional zone where the bottom is changing from a diffuse, non-alluvial headwaters to a wider floodplain with a definite stream channel and alluvial processes; correspondingly, the somewhat acidic Nyssa biflora forests of the headwaters (see plot ANTI011) are changing to alluvial swamps dominated by Nyssa aquatica and Taxodium distichum (see plot ANTI003). However, the plot was positioned near the edge of the floodplain, where fires occasionally burn down into the swamp, and more closely resembles the Nyssa biflora vegetation upstream. The forest here has a very open understory that has resulted from top kill of much Clethra alnifolia, Ilex opaca, Itea virginica, and Toxicodendron radicans. The stand is dominated by Nyssa biflora mostly in the 34 to 80 cm DBH range, with scattered Taxodium distichum, Acer rubrum, and other hardwoods also present. The herbaceous flora in the area of the plot is unusually lush and diverse for a Nyssa biflora swamp, with Woodwardia areolata and several forbs patch-delineating. It is not known whether the high herb cover is a response to burning.
