Vegetation change in created emergent wetlands (1988–1996) in Connecticut (USA)

  • Published source details Moore H.H., Niering W.A., Marsicano L.J. & Dowdell M. (1999) Vegetation change in created emergent wetlands (1988–1996) in Connecticut (USA). Wetlands Ecology and Management, 7, 1988-1996.


This study is summarised as evidence for the following.

Action Category

Reprofile/relandscape: freshwater marshes

Action Link
Marsh and Swamp Conservation
  1. Reprofile/relandscape: freshwater marshes

    A replicated, site comparison study in 1996 of seven freshwater marshes in Connecticut, USA (Moore et al. 1999) reported that created marshes had similar wetland plant richness, overall vegetation cover and woody plant cover to natural marshes, but greater cover of common reed Phragmites australis and cattails Typha spp. Statistical significance was not assessed. After 12–13 years, excavated marshes contained 25–53 wetland plant species (vs natural: 38–46 species) and had 80–123% total vegetation cover (natural: 90–130%). Key species with greater cover in created marshes included common reed (three of three comparisons; created: 2–29%; natural: <1%), narrowleaf cattail Typha angustifolia (three of three comparisons; <1–19%; natural: 0–11%) and broadleaf cattail Typha latifolia (two of three comparisons, for which created: 5–8%; natural: <1%). Woody plants had grown in both created marshes (10% cover) and natural marshes (16% cover). The study also reported data from 4–5 years after excavation (see original paper). Methods: In summer 1988 and 1996, vegetation was surveyed in four created marshes (excavated in 1983–1984) and three nearby natural marshes. All marshes were <1 ha, and the summer water table was 30 cm below to 22 cm above ground surface on average. Plant species and their cover were recorded in at least forty 1-m2 quadrats within vegetated areas of each marsh. This study used a subset of the marshes in (2).

    (Summarised by: Nigel Taylor)

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