SHELTERED from the pull of the tides, any sediment from the sea soon builds up into a skim of mud and silt. Over the years the layers of sediment evolve into saltmarsh. In summer, exposed to wind and sunshine, the lower mudflats dry out and are frosted by salt crystals; glasswort and annual seablite are the only plants to cope with the sudden shift from chilly ooze to salty desert. By contrast, the middle and upper levels of Holkham's saltmarshes are covered with plants. Sea aster looks like Michaelmas daisy and its flowers are a pale magenta; sea lavender forms extensive carpets and creates a misty-blue haze around creeks and grey levels. A closely related plant, the matted sea lavender, is a North Norfolk speciality and forms cushions rather than carpets.

Flea beetle

The plant which gives the upper marshes their distinctive character is the shrubby seablite. This is a dark green chunky shrub with a mass of tiny cylindrical leaves. Although it is common on the Norfolk coast it is very local anywhere to the north or west. It also has the distinction of being the first shelter when weather-blown migrant birds arrive on the coast, which is why bird-watchers pay seablite bushes special attention in October.

In the breeding season the mid and upper marshes ring to the loud, fretful call of the redshank, which nests in tussocks and feeds in the creeks and muddy saltpans. In the winter these same marshes are grazed by brent geese, shelduck and waders. Against evening sunshine the shimmering herds of grazing wildfowl and the wide horizon of the saltmarshes combine to create a lasting impression: one of the wildlife sights of Europe.

Sea aster                           Sea Lavender                                                                                     Shelduck