1 Sink Branch 1 Parcel B
 (18 years) (19 years)
 0.8 0.8

 0.6 0.6

 S0.4 0.4

 0.2 0.2
 0 0
 0.2I1, F I I 0 I I I l
 5 10 15 20 25 30 35 40 5 10 15 20 25 30 35 40
 DBH (cm) DBH (cm)



 Figure 7.5 (Cont.) Frequency Distribution of Tree Diameter at Breast Height from
 the Chrono-Sequence of Constructed Forested Wetlands. (Size
 Class Bins: 0-5 cm, 5.1-10 cm, 10.1-15 cm, 15.1-20 cm, 20.1-25
 cm...) Sites Appear in Chronological Order.


distribution patterns in Morrow Swamp and SP6 are strikingly different from those of the
other sites. Only a small percentage of trees sampled in Morrow Swamp fall into the <5
cm size class. Only one other site, Clear Springs Seep, had fewer trees in the <5 cm size
class than were found in larger size classes. SP6 displays a unique pattern of size class
distribution for an older site, with over 80% of trees in the <5 cm size class. In sites 18
and 19 years old, a small fraction of all trees sampled were in the >30 cm size class.
There were no trees in these size classes prior to 18 years.

 While a hierarchical distribution of size classes is apparent when tree species is
not taken into account, that individual tree species do not always fit this distribution
(Figure 7.6). Acer sp. shows a hierarchical distribution in four of the seven sites where it
occurs. In the other three sites, all Acer sp. specimens occur in the smallest size class.
Fraxinus sp. exhibits a hierarchical distribution in two of three sites. In the third site, the
greatest percent of the specimens are in the 0-5 and 5-10 cm size classes, while the least
is in the smallest size class. Taxodium sp. does not show a hierarchical distribution in
any of the sites where it occurs.

 Canopy tree species richness was greatest at C07984 (12 species) and second at
Sink Branch and Parcel B (10 species). From three to seven species were found at the


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