be determined with humans continually providing a diversity of seeds and evaluating
 which species become established.


 Subcanopy Trajectories

 Only weak positive trends with time were found in early successional subcanopy
 species richness and stem diameter, while no trends were found with late successional
 species. Salix caroliniana and Myrica cerifera are the most common species in the
 subcanopy structural category. Only the youngest sites and the two oldest sites had
 subcanopy tree species other than S. caroliniana and M. cerifera present. Subcanopy tree
 species were planted during reclamation in the three youngest sites. Subcanopy species
 were not on the planting list for the older sites and appear to have been naturally
 recruited. Only one of the two older sites was immediately adjacent to an unmined
 floodplain. The seed source for the other older site (Sink Branch) is unclear. Seedlings
 of Celtis laevigata and Comus sp. were present in the two oldest sites, although not in
 large numbers.


 Shrub Trajectories

 There are no clear trends in shrubs with site age, neither in decreasing trends in
 early successional species nor increasing trends in late successional species.
 Cephalanthus occidentalis was present in six of ten sites. It had been planted at each of
 the sites. Sambucus canadensis was present in five of ten sites and appears to be
 recruited naturally. Itea virginica was present at one site (16 years); it was not included
 on any planting lists and appears to have been naturally recruited.


 Understory Trajectories

 There were only a few weak trends in herbaceous understory vegetation
 associated with site age. This was explained in a previous section by the differences in
 species richness of marshes and forests with young forested wetlands more closely
 resembling marshes. The number of vine species and species of tree seedlings increased
 with site age. No other structural category increased in species richness with age. There
 are weak increasing trends in frequency of occurrence of canopy tree seedling and vines.
 Vines increased in both number of species and frequency of occurrence with site age.
 There was a weak trend with site age in the frequency of occurrence of early successional
 subcanopy species, increasing to a peak around 10 years and then declining.


 Soil Trajectories

 There is a weak trend in soils associated with age of wetland. Soil bulk density
decreases with time. If wetland hydrology has been successfully reproduced, and


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