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
17
m
Shrub Height
4
m
Field Height
2
m
Tree Cover
20
%
Shrub Cover
60
%
Field Cover
40
%
Misc Fields:
Observation Narrative
Both sides of unnamed tidal channel off Holts Creek are lined with fringe thickets of Alnus serrulata beneath a thin canopy of scattered Nyssa biflora and Fraxinus profunda. Interspersed with shrub patches are herbaceous openings dominated by Zizania aquatica. Away from tidal channels vegetation grades into more closed tidal hardwood forest with a well-developed but less dense shrub layer. Although this plot was established with the intent of sampling a true Alnus shrubland, the sample captures principally woodland vegetation. A releve rather than intensive plot was sampled due to limited time, number of participants, very dense understory vegetation, and difficulty in assigning presence to a particular spatial scale. It was difficult to determine optimal plot location and orientation to capture homogeneous vegetation and characterize composition accurately. An Alnus fringe of varying depth appears to represent a distinct, recurring vegetation type (or possibly types), despite their underrepresentation in data from tidal systems. It is unclear, however, whether some contemporary stands of tidal shrubland represent former tidal hardwood swamps that have experienced severe crown stress and significant canopy mortality as a result of chronic sea-level rise.
From flagged Nyssa biflora (ca. 22 cm dbh): 1.9 m @ 323 deg to corner 1.
