cover. Stand characteristics such as stem density, tree basal area, and canopy height
throughout the chronosequence sites are given in Table 6.7.


 Soil Characteristics

 Soils data from all of the square meter quadrats were analyzed to explore what
conditions support vine growth. Soil moisture, bulk density, percent organic matter, pH,
and plant available nutrients were determined from soil cores taken within each square
meter quadrat. Some threshold levels and trends were apparent. All of the soil
parameters have been compared to both the number of rooted vines and dry weight vine
biomass.

 Table 6.10 summarizes the data for soil moisture, dry bulk density, and soil
organic matter for the chronosequence sites. Values given are the mean for each site 
the standard deviation. Values without standard deviations have been calculated using a
single soil core. Some of the soil cores were excluded due to possible improper field
techniques or laboratory processing. Note the unusually low mean dry bulk density of
0.52 ( 0.44) g/cm3 at Guy Branch.

 Although soil moisture data result from synoptic sampling and does not represent
absolute soil moisture associated with vine rooting it does indicate vine rooting zonation
based on a range of soil moisture. Figure 6.15 shows all of the herbaceous and woody
rooted vines occurred within the range of 5%-45% soil moisture, with a range of 0-60
herbaceous vines and 0-20 woody vines rooted per square meter. The herbaceous rooted
vines were concentrated within the 25-45% soil moisture range, while the woody rooted
vines were concentrated within the 5-25% soil moisture range. Three outliers occurred
between 83-85% soil moisture. All three samples were from cores taken at Guy Branch.
Most likely these values were incorrect due to the mean standing water depth of 40 cm at
Guy Branch, and difficulty in the field separating standing water from soil cores. All of
the harvested vine biomass occurred in areas with soil moisture ranging between 5-45%,
with the exception of the same three outliers from Guy Branch.

 Profiles of each transect beginning in the upland-transitional ecotone regions and
progressing into the wetlands suggest a zone of soil moisture that favors vine growth.
Figures 6.16 and 6.17 illustrate soil moisture trends on transects from Hydric Hammock
and Sink Branch, respectively. The remaining transect profiles relating to soil moisture
are provided in Appendix 6.E. Figure 6.16(B) shows that when the soil moisture is below
20% there are less than 5 rooted vines per meter square, yet when soil moisture increases
to 25% there are nearly 30 rooted vines per meter square. Figure 6.17 depicts a similar
trend evident at Sink Branch. On transect 2, when the soil moisture ranges from 10-20%
there are approximately 10-20 rooted vines per square meter. However, as soil moisture
increases to over 30%, less than 5 vines are rooted per square meter.

 Figure 6.18 provides the less evident threshold levels of dry soil bulk density
(g/cm3), suggesting that soil substrate is not a dominant factor in determining vine


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