stress, or if aesthetics are of real concern, more dense plantings of herbaceous plants 

 are recommended. When trees are part of the wetland development scheme, they 

 must be adequately spaced (2 to 5 meters) to survive and grow properly. To reduce 

 stress and washout, the young trees may be surrounded by a planted herbaceous 

 marsh to give them temporary protection. For example, smooth cordgrass is planted 

 in Florida to act as a buffer for mangrove transplants and seed pods, and serves until 

 the mangroves take root and crowd out the grass (R.R. Lewis III, Mangrove Systems 

 Inc., Tampa, Florida, personal communication). 



Planting Schedule 



In general, plants may be established at any time the ground is not frozen. 

 However, spring months (April-May) are usually best because the propagules will 

 have an entire growing season to establish a good root system prior to winter 

 dormancy. Biological preparations such as gathering and storing propagules should 

 take place while the engineering phase is being completed. An entire growing season 

 can be missed if proper preparations are not made in a timely manner. 



Pilot Study 



A pilot study should precede large, costly wetland projects, or projects in which site 

 conditions make success less than certain. The pilot study is a small-scale version of 

 the larger project, and should be designed to anticipate problem areas prior to 

 full-scale construction. 



Natural Colonization 



If the cost of planting a wetland is prohibitive, the site may be prepared at an 

 appropriate elevation and natural colonization allowed to take place. Natural 

 colonization may take only a few months in the case of freshwater wetlands, or it 

 could take as long as 10 years in salt marshes. The major disadvantages to natural 

 colonization are that undesirable plant species may invade the site or the site may be 

 washed away before plants can provide stabilization. 



Monitoring 



A site should be monitored after planting to determine species survival, plant 

 growth, site changes, and succession. At a minimum, monitoring efforts should note 

 site succession, species diversity, productivity, wildlife use, and changes in elevation 

 and substrate conditions. 



Problems 



Some of the more common problems in wetland development are: lack of 

 coordination between engineering and biological personnel, project/ planning mis- 

 timing, incorrect selection of plants and propagules, contaminant uptake into plant 

 shoots that wildlife may consume, invasion of undesirable plant species, pest wildlife 

 and feral animals on a site, plant diseases that may be introduced to a site, and cost. 



SUMMARY 



America's wetlands are disappearing at an alarming rate, but private citizen and, 

 public agency actions reduced the annual destruction rates to some degree during the 

 1970- 1980 decade. Wetland protection and management are essential to maintain the 

 health, vigor, and usefulness of our wetlands. Wetland development may be used to 

 enhance or improve existing wetlands, to build wildlife habitat, or to build wetlands 

 where insufficient areas previously existed. Technology is developed and available 

 for use in wetland construction of all types, and the expertise is available upon 

 request from such agencies as the CE and the FWS. 



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