Four separate simulations were run representing forested wetland succession
 following site establishment, forested wetland succession in the absence of vines,
 forested wetland succession when vine management occurs in year 7, and forested
 wetland succession when vine biomass is controlled when the storage of herbaceous vine
 biomass equals 20%.

 Figure 6.43 shows the results from the model of forested wetland succession
 following site establishment. Initial values for the storage of herbaceous vine biomass
 (5%), woody vine biomass (8.3%), tree biomass (30%), tree nutrients (6%), and organic
 matter (7.8%) were assigned according to the percent of the steady state storage present
 during site establishment. Initial vine biomass represented seeds and viable vine
 segments present in the applied mulched layer and as litter fall from surrounding areas in
 the landscape. Tree biomass and nutrients values reflected that associated with planted
 stock. The organic matter storage represented the mulched layer applied to the forested
 wetland surface during wetland establishment.

 This initial run suggested that herbaceous vine biomass peaked at approximately
 5-15 years, followed by a marked decline through year 25. Herbaceous vine biomass
 remained within the ecosystem throughout forested wetland maturity. Woody vine
 biomass entered the system between 5-10 years after site establishment, reached steady
 state at around 35 years, and remained in the system through maturity. Tree biomass
 reached maturity at around 100 years after site establishment. Within the first 10 years of
 site establishment, tree biomass grew rapidly, followed by slower growth through
 maturity. Soil organic matter closely followed the peak and decline of herbaceous vine
 biomass, with maximum organic matter storage at approximately 10-20 years. This
 suggests the important role vines play in the creation of organic matter.

 To explore the role of vines further, a second simulation model was run, reflecting
 forested wetland succession, tree biomass development, and organic matter storage in the
 absence of vines. Initial values for tree biomass (30%), tree nutrients (6%), and organic
 matter (7.8%) were unchanged, while the initial storage values of herbaceous and woody
 vine biomass were set at zero. Figure 6.44 shows tree biomass grew slowly without
 reaching the steady state level within the first 200 years of forested wetland succession.
 Additionally, the storage of organic matter remained extremely low in the absence of the
 contributions from vines.

 A third simulation was run to test the hypothesis that vines play an important role
in forested wetland development, and that by removing vines from systems during
development, the systems may be delayed in reaching maturity. For this run, the
management switch representing vine removal was activated in year 7 representing
herbiciding and physical removal of vine biomass from the wetland.

 Figure 6.45 shows a sharp decline in the storage of herbaceous vine biomass at 7
years, followed by a peak at 10 years, and a decline in herbaceous vine biomass, with
some threshold storage level remaining throughout maturity. Woody vine biomass was
also knocked back in year 7, followed by a low level of woody vine biomass through year


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