the number of individuals. Mean shrub density of late successional species was lower
than that of early successional species in all sites except SP6. Mean shrub stem diameter
ranged from 0.3-3.0 cm. Greatest stem diameters were found in the intermediate age
sites (8-10 years) and in the two oldest sites (18 and 19 years). Early successional
species stem-diameter ranged from 0.3-3.0 cm. Late successional species stem-diameter
ranged from 0.3-3.4 cm.

 Shrub species richness ranged from 0 to 5 species per site. Sambucus canadensis,
 Baccharis halimifolia and Cephalanthus occidentalis were present in 57%, 57% and 50%
 of the sites, respectively. Ludwigia peruviana was present in 100% of the sites (Sink
 Branch and Morrow Swamp had primrose willow present, but it was not within a
 sampling quadrat). Itea virginica was present at both Morrow Swamp and SP6 but was
 sampled at only one site, SP6. Schinus terebinthifolius, an invasive exotic, was present at
 Parcel B and was observed but not sampled at SP6. Ludwigia octovalis was found in one
 site.

 Species diversity ranged from 0.0 to 0.59. Species diversity was greatest at
 CO7984 (5 years) followed by Parcel B (19 years). .Species diversity was least at SP11
 and Morrow Swamp where only one shrub species was sampled. Species evenness was
 lowest at Sink Branch (0.32). At all other sites, species evenness ranged from 0.52 to 1.0.


 Understory Species

 All species occurring in the research are listed in Tables 7.7 and 7.8 along with
 their frequency of occurrence. Herbaceous species richness ranged from 7 to 32 species
 (Table 7.9). Species richness of all vegetation included in the understory category ranged
 from 13 to 41 and was greatest at C07984 and East Lobe. Of canopy species, Acer sp.,
 the most common species, was found in all sites where seedlings occurred. Quercus
 laurifolia was the next most common species and was found in thirty-six percent of the
 sites. Ten of the fourteen sites had seedlings or saplings of subcanopy species present;
 however, no site had more than 2 species occurring. Shrub seedlings or sapling occurred
 in all sites sampled except LP2 Phase 1, the youngest site. Vines occurred in all but the
 two youngest sites. The greatest number of vine species (11) occurred in Sink Branch
 (18 years).

 Species diversity in the understory ranged from 1.08 to 1.57. Species evenness
neared unity for all sites (0.90 to 1.0) and was less than 0.90 in only one site (0.86 at
SP6).

 The understory community status is provided in Table 7.10. Those sites with the
lowest "Understory Community Wetland Status" contain a greater probability of
sampling wetland species and perhaps a greater probability of being a wetland. Figure
7.7 is a graphical representation of community wetland status. The horizontal line in
Figure 7.7 represents the average "Understory Community Wetland Status" of all sites
sampled. Six of the research sites have a lower than average status suggesting that they


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