Marsh can be defined as land that is waterlogged for at least part of the year. Marsh land is not common in the Kent Downs AONB because of the free-draining nature of much of the underlying rock such as chalk. However, small areas of marsh can be found which are important for wildlife and contribute to the variety of the landscape.
Marshy areas usually contain plants such as rushes, sedges and reeds with wild flowers such as marsh marigold (also known as kingcup), yellow flag iris, marsh orchids, water dropwort, water mint and marsh thistle. In the absence of management such as grazing or mowing, the marsh is invaded by shrubs and trees such as willow and alder and gradually develops into wet woodland. Many of the marsh plants disappear in the shade of the shrubs and trees. You can find out more about wet woodland in the woodland section on the website.
Marshy areas can be found at the base of the Downs where springs are commonly found when water percolating through the chalk meets impermeable clay layers. Marshland in calcareous (chalky) areas is often referred to as fen, and marshland on acid (sandy) soils is often called bog. A good example of a spring-fed calcareous fen can be found at Holywell Fen, Folkestone Downs. Wet and acid conditions can prevent the decay of plant remains leading to the formation of peat, a very rare habitat in Kent, which can be found in places such as Gibbins Brook, near Sellindge. A great deal of marshland has been lost, having been drained and ploughed for agriculture. This is particularly the case on Romney Marsh, a small area of which is included in the Kent Downs.
The Romney Marsh
The Romney Marsh is an area of approximately 150km2 of reclaimed marshland crossed with drainage ditches. The land use is mainly agricultural with a mixture of arable and livestock farming. Water levels are artificially raised in the rivers, canals and other larger drainage ditches (known as sewers) across the main body of the Marsh. The sewers and drainage ditches across marshland are not only essential for the drainage of land, they also provide valuable habitat for a number of rare and protected species including water vole, great crested newt, marsh mallow, greater water parsnip and medicinal leech.
The Romney Marsh is the best place in Europe for wild populations of medicinal leech and also is one of the national strongholds for the water vole. The Marsh’s proximity to Dungeness National Nature Reserve (NNR) means that many rare bird migrants are recorded here throughout the year. These migrants are attracted to the marshland areas where they can feed and breed. Sympathetic management of the ditches is essential in order to preserve the populations of all of these species. This section aims to provide as much information as it can to allow those that have responsibility for the management of drainage ditches and marshland, to make the correct decisions and ensure that the landscape and wildlife of the marshland is retained.