flora and fauna
Cuckmere Haven is famed for its Saltmarsh environment between the flood bank and the tidal river, a salt marsh has developed which is covered by most tides. The level of the mud is slowly, but constantly rising. At slack water either side of high tide, the suspended silt particles, which have been brought down by the river, sink and are deposited around the roots and stems of salt marsh plants. These are specially adapted to living in a soil with a very high salt concentration and are called halophytes.
The bare mud is first colonised by the fleshy succulent green glasswort Salicornia sp. but as the level of the mud rises and is covered by water for a shorter time, other plants become established. These include sea purslane Halimione portulacoides which has flattened grey-green leaves, sea spurrey Spergularia media, which may be distinguished from the similar sea blite Suaeda maritima when not in flower, by the whitish scale at the base of the leaves, and the red fescue grass Festuca rubra. Still higher and reached only by the highest tides are the grey-green sea wormwood Artemesia maritima and the mauve-flowered sea aster Aster tripolium. The seed and fruit of these plants are mainly dispersed in sea-water by the movement of the tides.