Figure 6.24 shows that the number of herbaceous and woody vines rooted and
 vine biomass appeared uniform throughout the entire 1-133 g iron/ m3 range of soil iron
 concentrations. The three samples with iron concentrations greater than 100 g iron/ m3
 occurred at three different sites (SP11, Morrow Swamp, and Sink Branch) again
 suggesting natural inter-site variability.

 Soil nitrogen concentrations as ammonium (NH4-N) and nitrate (NO3-N) were
 compared to occurrence of rooted vines and dry weight vine biomass. Figure 6.25 shows
 that almost all of the rooted vines and dry weight vine biomass were located in areas of
 0-1 g NH4-N/ m3. Only five data points had concentrations greater than 1 g NH4-N/ m3
 hosting both herbaceous and woody vines. Similarly, Figure 6.26 illustrates that a
 majority of the rooted vines and dry weight vine biomass were located within the 0-2 g
 NO3-N/ m3 range. However, many vines were scattered throughout the entire soil nitrate
 range of 0-4 g N03-N/ m3.


 INTENSIVE SAMPLING DESIGN

 Six wetlands were sampled with an intensive sampling design for rooted vines
 and dry weight vine biomass, mean vine basal diameter, vegetative cover, vine leaf area,
 sunlight transmittance, water depth, and soil parameters.


 Vegetative Data

 Figure 6.27 shows that every site sampled intensively had at least 2.5 rooted
 herbaceous vines per square meter, and over 20 grams of dry weight herbaceous vine
 biomass per square meter. Only three intensive sample sites had rooted woody vines,
 including Hydric Hammock with 2.5 rooted woody vines, Cateye with 3.5 rooted woody
 vines, and SP11 with 2 rooted woody vines per square meter. There was greater woody
 biomass at both Hydric Hammock and Cateye than herbaceous vine biomass. However,
 SP11 was dominated by herbaceous biomass. The standard deviations of both rooted
 vines and vine biomass are extremely large, suggesting great heterogeneity throughout
 the landscape. Figure 6.27 also shows that the mean vine basal diameter varied
 considerably, with no significant differences between sites.

 Figure 6.28 illustrates that vines occurred throughout all class of herbaceous
understory vegetative cover. Herbaceous vines occurred throughout quadrats with
greater than 10% herbaceous understory cover, and no woody vines occurred in areas of
10-25% herbaceous understory cover. Quadrats with no vines were represented by
herbaceous ground cover greater than 25%.

 Vine leaf area appears to show a weak correlation with site age. Figure 6.29
shows that the greatest leaf area (number of leaves per square meter) occurred around age
7 years, with a decrease in the vine leaf area as a site ages. Additionally, mean vines leaf
area was not significantly different throughout varying degrees of vegetative cover. The


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