including Ampelopsis arborea, Melothria pendula, Momordica charantia, Passiflora
incarnata, Smilax spp., and Vitis spp. (Table 6.6). All of these vines were found growing
on sites six-years or older, suggesting that there may be a direct correlation between the
presence oftendrillar vine species and increased forest maturity.

 At six-years, the forested wetlands studied had an approximate canopy height of 3
meters and a basal area of 4 m2/ha (Table 6.7), which correlated to approximately 50%
sunlight transmittance through the canopy (Figure 6.13). Vine leaf area peaked around 6-
7 years (Figure 6.29). Although forest maturity is hardly complete by age 6, the
definition of forest maturity may need to be modified to stress the onset of canopy
closure by early successional subcanopy species. Additionally, most of the studies on
vines have been conducted in tropical systems where lianas (large woody vines) dominate
the systems. These tropical systems have greater turnover times, taller canopies, and
greater structure.

 The initial run of the computer simulation model reflects these successional
conditions with increasing tree biomass and a peak of herbaceous vine biomass between
5-10 years after site establishment (Figure 6.43). The wetlands sampled in the
chronosequence design do not reflect forested wetlands at maturity, but rather forested
systems progressing through succession. According to the model, the herbaceous vine
biomass levels off at by year 20, whereas the oldest site sampled was 18-years-old. Tree
biomass reaches a steady state level at approximately 100 years after site establishment,
with well over 80% of the steady state biomass achieved by 50 years. Woody vines enter
the system at approximately 5 years after establishment, and reach a steady state level by
approximately 25 years.

 The second run of the model demonstrates forested wetland succession and tree
biomass development in the absence of vines (Figure 6.44). In this simulation, tree
biomass at maturity is greatly reduced without the storage of organic matter created by
vines. Vines may in fact make important contributions to organic matter accumulation
and therefore the successional development of tree biomass (Bush and others 1995;
Castellanos 1992; Putz and Mooney 1989).

 Vines may be important to forested wetland development, and vine removal may
be unnecessary and possibly even detrimental to timely system self-organization of
developing forested wetlands (Figure 6.45; Figure 6.46). To discover the effects of
management by means of biomass removal of vines two simulations were run mimicking
management in the form of herbiciding and removal of vine biomass. These simulations
showed delayed accumulation of organic matter following closely with the delayed peak
of herbaceous vine biomass. The lack of organic matter and therefore vine biomass may
contribute directly to the natural succession of forested wetland systems. It appears that
by removing vine biomass throughout succession organic matter accumulation in the
system is reduced.

 Competition between herbaceous vines, woody vines, and trees for available
 sunlight and nutrients is also visible when woody vines do not recover after initial


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