Flooding the wetland had the added effect of increasing the soil pore water in the
 hummocks. Figures 5.24 and 5.25 show that the organic hummocks have higher
 volumetric water content than the overburden hummocks as expected based on the
 properties of organic and mineral soils. An increase in number of species, Shannon
 diversity, and percent cover accompanied the increase in soil pore water. The water
 pumped into the wetland likely had background levels of phosphorus, which were
 utilized by the growing vegetation. The muck hummocks, which were exposed to
 oxygen, would have added nutrients to the soil upon decomposition. The overburden
 soils, because of their origin, also contain background amounts of phosphorous, which
 plants could uptake as pore water increased. The muck hummocks likely had greater
 diversity and percent cover due to more available nutrients and higher soil moisture.
 Figures 5.16 and 5.17 show the two hummock types to have similar ranges of soil
 moisture providing a similar distribution of micro-sites for vegetation growth. Organic
 hummocks have higher values of soil moisture at similar elevations than do overburden
 hummocks. This would be expected based on the characteristics of organic and mineral
 soils.

 Based on initial data, these two hummock soil types provide similar benefits in
 terms of stability and colonizing vegetation. Tree data may provide the defining
 characteristic when chosen between the two soil types. Due to the late construction of the
 site during this study, only initial tree data were available and no comparison can be
 made.


 WETLAND COMPARISON

 Comparing the hummocks in the Agrifos and Cargill wetlands becomes difficult
due to the difference in time of construction and the conditions found in each wetland.
Because the Cargill wetland was not completed until late in the growing season, only two
sampling periods of data were taken. These can be compared to the first two sampling
periods in the Agrifos wetland, but they occurred at opposite ends of the growing season.
The samplings taken at the end of the growing season can be compared, but the wetlands
are slightly different ages. In the early growth of the wetlands, the small age difference
could influence data. The difference in flood stage of the wetlands also makes
comparison difficult. Water level greatly influences soil moisture and nutrient
availability, which in turn affects the vegetation growing on the hummocks. None-the-
less, the comparison will be made between the two new wetland hummocks and the third
elder Iluka wetland hummocks.

 The stability of the hummocks in the three wetlands begs the first comparison.
The hummocks in the Iluka wetland show a slight growth as opposed to the decay seen in
the infant hummocks in the other two wetlands. The soils in the older hummocks have
already undergone the period of settling and compaction, which takes place in newly
disturbed soils. The newly constructed hummocks in the Cargill and Agrifos wetlands are
still experiencing the settling, which accounts for some decay. The mature hummocks in
the Iluka wetland also have more vegetative root structure to provide soil stability than do


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