Milton D. Taylor

Floral Colonization of a Free-Water Surface Constructed Wetland System in Grady County, Georgia

ABSTRACT  A comprehensive survey of the vascular flora of a constructed wetland in Grady County, Georgia was conducted at monthly intervals between August 2004 and May 2006. The constructed wetland is used as a part of a nutrient remediation system to improve the sustainability of plant nursery water-handling practices. The survey evaluated vegetation in a 3.1 ha, two-stage constructed wetland consisting of two deep cells (Stage 1; mean depth 0.75 m) totaling 1.8 ha that drain into two shallow cells (Stage 2; mean depth 0.2 m) totaling 1.3 ha. Each cell was band planted in 1997 with seedlings or liners of six wetland plant species. During the 2-yr survey, 141 distinct species were collected from the 3.1 ha constructed wetland; of the taxa collected, there were 101 genera from 51 families. Native taxa made up 76.6% of the species recorded, and 24.1% of the taxa were introduced. Hydrophytic plants accounted for 68.1% of the plants collected and the remainder (31.9%) were classified as nonhydrophytes. Because 57.4% of the taxa surveyed were perennial, it is likely that plant propagules introduced by wildlife (waterfowl, reptiles, and amphibians) were the dominant method of plant introduction rather than primary succession. Vascular plant community diversity increased 24-fold during the 9-yr period after constructed wetland installation.