Anyone who has taken part in an NWT corporate work party, or who regularly volunteers on our reserves, knows winter is when the hard-work is carried out. It is a time when boots are needed on the ground, a time when invasive scrub is cleared, and a time when we maintain the vast network of dykes that dissect our reserves, particularly in the Broads.
Most of our grazing marsh dykes are maintained by the assistance of modern machinery. However, the more wildlife sensitive and hard to reach dyke systems have to be managed in a traditional manner. And it is a process that would be recognised by any marsh-worker from across the centuries.
Exploring the low-lying areas of Norfolk through an Ordnance Survey map, one finds the landscape criss-crossed by a multitude of thin blue lines. These, of course, represent a myriad of dykes and ditches. Most were dug by hand decades ago; in fact, many have sat in our landscape for centuries. Our ancient countryside would have been considerably wetter than it is now, however, once drained, these saturated wetlands formed fertile land for farming. Ditches and dykes soaked away excess water into rivers, and these were often straightened and their banks raised to allow a quicker flow to the sea. In the Broads, sitting at or below sea-level, wind-pumps were employed to hasten this drainage. Ditches and dykes also formed obvious boundaries and barriers, with deeper cut dykes on grazing marshes acting as ‘wet-fences’ for livestock.
The Norfolk Wildlife Trust’s Broadland nature reserves contain over two hundred kilometres of dykes. Key sections are now installed with water control structures, such as drop-board dams. This allows us to keep control of water levels, particularly in summer, so as to maintain the boggy ground of a healthy fen.
Just a century ago these wetlands were of high value and included many important commodities. The meadows provided hay and fodder for farm animals, with large quantities being sent to London for its half-million horses. Reed and sedge beds provided roofing material and the marshes grazing for cattle. The maintenance of the dyke systems required a team of marshmen working in a constant rotation, ensuring the dykes were free of excessive waterweed, the banks trimmed of rank vegetation, and any blockages quickly cleared.
The technological age very soon turned its back on the produce of our wetlands. Surprisingly quickly, reedbeds scrubbed over, dykes skimmed across with vegetation, and our developing modern world added pollutants and over-enrichment from nitrates and phosphates.
Although the Broads and surrounding marshes were, to a large extent, created and manipulated by people, this in part replicated the lost river floodplains and vast East Anglian wet fenlands. As such, this area became an oasis for many unique animals and plants. Neglect during the 20th century led to changes in habitat structure becoming, through natural succession, willow and alder scrub. This change of habitat started to threaten the survival of the Broads’ exceptional wildlife. Iconic species like swallowtail butterfly, bittern, bearded tit and fen orchid, to name just a few, dwindled in number. Many became restricted to the last remaining suitable habitat and, without intervention, faced local and even national extinction.
Norfolk Wildlife Trust, along with other conservation bodies, identified that the traditional management of wetlands was vital to restore these precious and bio-diverse habitats, and that decades of work was required to reverse their decline. The dykes that run through Broadland nature reserves are effectively ‘long-ponds’ and exceptionally important wildlife habitats. Most dykes are cleared on a two to five-year rotation, which ensures they are at varying degrees of natural succession and allowing for greater bio-diversity. Although mechanical diggers are often employed, where access is difficult or the intervention too invasive, NWT staff and volunteers use traditional hand tools. These tools could be viewed as antiquated, and certainly erstwhile marsh workers would have no trouble recognising them, but they still do the job. The names would trip, with a Norfolk twang, from their tongues. Names such as a shore-knife (for cutting the dyke edge), dyke ladle, (for scooping out silt), crome (a bent fork for dragging out vegetation), or maige (a long-handled scythe blade).
Ensuring the dykes do not become too choked with plant growth, particularly with reed, is vitally important. If dykes do get blocked, it can prevent the flow of freshwater across and through the whole marsh. Many of the rarer Broadland plants prefer a gradual flow of fresh groundwater through the marsh and without the dyke system the water can stagnate, reducing and changing the floral community.
After clearing bank-side vegetation with brushcutters, which are effectively petrol-driven meadow scythes. The cut vegetation, mostly reed, is pitch-forked into the nearby alder/willow Carr. Allowing it to rot down in the woody scrub ensures that any addition nutrients do not leach into the dykes. Once the bank is clear, the long handled maige is sunk into the dyke and a specific snatching jerk is required to cut free the reed rhizome. Success finds the reeds’ long white tubers floating to the surface. It is important to keep the blade sharp, so a whetstone is deployed after the clearance of a few yards of dyke. Along with other aquatic weed and algae blankets, the cut vegetation is dragged out of the dyke with the crome. The maige is also employed to cut back the peaty edge of the bank. All this material is hoicked into the undergrowth to rot down, well away from the dyke edge. Teamwork is essential to get a good rhythm going, one maiging, one croming, and one pitching. Although, many would argue that maiging is an art only managed properly by those with experience and skill.
During January and February, in a biting east wind, this is not work for the faint-hearted. Despite this, it is worthwhile. Although most people won’t have heard of these tools, or many of the creatures that inhabit marshland dykes, rest assured that our wildlife benefits from this old-fashioned care.