Stem density for Myrica sp. was reported as 400, 200 and 800 stems ha"' in
 cypress domes, bayheads and hardwood swamps, respectively (Davis and others 1991).
 This study found stem densities ranging from 420 to over 10,000 stems ha-'. The
 relatively large number of stems reported in this study may result from data collection
 methods. Each stem reaching above lm was counted and measured regardless of origin.
 Therefore, the growth architecture of Myrica sp. and Salix sp. results in multiple stems
 and does not represent the number of individual plants. The definition of a stem is not
 clearly stated in other studies. Regardless of methodology, Myrica sp. is a component of
 natural and constructed forested wetlands.

 Clearly, there is a lack of species richness in the subcanopy component of
 constructed forested wetlands. Perhaps Myrica sp. and Salix sp. are able to out compete
 other subcanopy species until community basal area (and the corresponding increase in
 below-ground competition), and lower light levels accompanying canopy closure create
 conditions where other subcanopy species have a competitive advantage.


 Shrub Species

 Shrub species are a component of most wetland systems including marshes, where
 they are often relegated to the ecotones between wetland and upland. Davis and others
 (1991) reported that the number of shrub species found in Florida wetland communities
 ranged from 13 species in bayheads and 19 species of shrubs in marshes and cypress
 domes, to over 30 species of shrubs in hardwood swamps. However, a list of the ten
 most common shrubs provided by Davis and others (1991) included Myrica sp., which in
 this study is considered a subcanopy tree, and several vine species, which are treated
 separately from shrubs in this study. Even when including Myrica sp. and vines in the
 total number of shrubs found in constructed forested wetlands in this study, there were
 considerably fewer (0-15) shrub species than in hardwood swamps. This is only half the
 species richness of hardwood swamps. Of the four most common shrubs occurring in
 natural wetlands (Davis and others 1991) that were also considered shrubs in this study
 only Cephalanthus occidentalis and Vaccinium sp. occurred in both natural and
 constructed sites. In sites where these species occurred, they were included in planting
 during construction or were part of supplement planting after establishment of the
 canopy. There is evidence of recruitment of shrubs, considered desirable by regulatory
 agencies, in only a few older sites.


 Understory Species

 Understory species include all structural categories, but will be discussed by
individual category for clarity and comparisons. Herbaceous species richness ranged
from 7-35, with the greatest number of herbaceous species found in the younger sites.
Herbaceous species richness in constructed forested wetlands although similar to that of
bayheads (26 species) falls short of that reported for marshes (157), cypress domes (74)
and hardwood swamps (111) (Davis and others 1991). In light of the differences in


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