To improve wetland restoration and the standards that drive their design, we examined vegetation data for the DMS wetland and stream mitigation projects across the state of North Carolina. Because the CVS-EEP database contains repeated measures of plant performance in mitigation sites across the entire state, it provides a unique opportunity to evaluate plant growth and community change in a variety of different ecological settings and across many mitigation projects.
Previous studies have shown that trees planted on highly disturbed and compacted soils of mitigation sites often exhibit slower growth rates than those on natural sites. Therefore, we wished to determine the performance of woody species on mitigation sites and to understand how these vary by species, project, and within sites We also wished to determine how height and density of woody stems on mitigation sites compare to the ACOE criteria for successful mitigation.
Current regulations rely solely on performance (survival and growth) of planted stems to assess mitigation success, without considering the effects that volunteer stems have on stand growth and species composition. Therefore, we also wished to determine how the volunteer stems are contributing to community development of these sites.
Specific objectives for this study were to:
(1) assess the quality and utility of the CVS-EEP database,
(2) evaluate growth and density of woody stems on mitigation sites, and
(3) to compare community composition between planted and volunteer species.