Background

Background information

Restoration of coastal marsh and dune habitats focuses on planting the appropriate species of plants in the correct “zone” for their survival. Zonation is a common feature of intertidal habitats, as certain species of plants are better adapted to tolerate abiotic (tides, salinity, waterlogged soils) stressors, while other species are better competitors for space and resources. In Mississippi and along the northern Gulf, there are 3 general zones:

• 1.Spartina alterniflora (= Smooth Cordgrass) - a bright green fringe right along the water’s edge, often called the “low marsh”.

• 2.Juncus roemerianus (= Black Needlerush) - a dark olive green band of varying width that is the main zone found in our coastal saltmarshes. It is sometimes referred to as the “mid marsh” zone.

• 3. A zone of mixed species including Spartina patens, Distichlis spicata, Scirpus robustus, Salicornia bigelovii, Baccharis halimifolia, Iva frutescens, Borrichia frutescens, among others. This zone is the “high marsh” and occurs at the landward edge of the saltmarsh.

Typical zonation pattern found in Mississippi saltmarshes.

For successful restoration it is very important that species are planted in the correct zone, which may require surveys of elevation to better than 1 inch accuracy. If a species is planted outside it’s optimal zone, it will likely die or be replaced by a better competitor. In both cases the investment made in plants obtained from the nursery will be lost, and restoration success will be reduced.