Atlantic salt meadows are found in the middle and upper reaches of estuarine saltmarshes where, although covered by the sea during the medium and higher tides, inundation occurs with less frequency and duration. These salt meadows can be extensive, especially where the landward side hasn’t been enclosed. The vegetation varies according to climate, the frequency and duration of tidal inundation and grazing pressure. The habitat is typically species-poor and dominated by species with a high tolerance to salinity and grazing, e.g. common saltmarsh grass (Puccinellia maritima) in the lower saltmarsh and red fescue (Festuca rubra) in the upper marsh. The grazed saltmarshes of Carmarthen Bay (see image) include upper margins with sea rush Juncus maritimus and marsh-mallow Althaea officinalis, with the latter a distinctive feature of the site. The area is also important for transitions from saltmarsh to sand dune and other habitats.

Most salt meadows in Wales are intensively grazed by sheep and/or horses, which has a significant impact on the habitat structure and composition of the flora and fauna present, notably influencing the diversity of invertebrates and breeding or wintering waders and wildfowl the habitat can support.