BSNHS

©BSNHS 2014

Archive

Sawbridgeworth Marsh 1966 - 2015

Sawbridgeworth Marsh

Sawbridgeworth Marsh

Sawbridgeworth Marsh Nature Reserve was purchased in the very early 1970s by the then Essex Naturalists Trust and the Herts and Middlesex Naturalists Trust. There was some competition between the Trusts and the neighbouring farmer who considered the Marsh as a "source of weed seed" and wanted to dig it out to make a Lake probably after gravel extraction.

John Fielding was instrumental in pointing out the botanical significance of the Marsh in conjunction with a survey done by John Dony and an account of the Marsh appeared in the Flora of Herts. The area was purchased for the sum of £1000.

These archived items show some early photographs along with reserve records and the results of survey work done by Alec Martin on the microscopic life in the ditches particularly algae and diatoms.

My Quarter Century on the Marsh - Andy Sapsford Marsh Warden

It is not only the Bishop’s Stortford Natural History Society that has a landmark anniversary this year. I have a small one of my own – it is 25 years since I first began working regularly on Sawbridgeworth Marsh Nature Reserve.

This reserve, situated just to the north of Sawbridgeworth adjacent to the old river Stort, is a jewel in the crown of the Essex Wildlife Trust. It consists of 22 acres of botanically rich wetland – 6 acres of wet rush pasture, 10 acres of sedge and reed beds and a 6 acre former Cricket bat willow plantation, lying to the south of both of these areas and standing itself on flower rich swamp. It was jointly purchased by the Essex Wildlife Trust (EWT) and Herts & Middlesex Wildlife Trust (HMWT) (then both known as Naturalist’s Trusts of course) when it became available for sale in 1969 – 1970. The original warden was John Fielding, who had known the site for some years and had shown it to John Dony, when he was surveying for his county flora in 1962. John Fielding managed the reserve until about the mid – 1980s. There were a couple of wardens after that, Julian Smith and Julian Thompson, but the reserve was effectively wardenless at the end of the 1980s for about a year.

So it was that Chris Swan, who had agreed to take over as warden, Bob Reed and I met up on the early evening of Saturday 21st April 1990 and began the first practical task – the removal of a crack willow that had fallen into the Alec Martin Pond.

During the months that followed, we tackled the various tasks involved in restoring the reserve, including relocating the path network under the vegetation, getting the sedgebeds and reedbed marked out into plots and installing a cutting rotation for them, recutting overgrown pollards and starting new ones and digging out the old channels that had originally lined the paths in order to create open water habitat on the reserve. In 1993, Chris became warden of the Hatfield Forest Marsh, then still an EWT reserve. I was invited to take over as warden on the marsh, which I was very pleased to do.

Much of the management work continued as before, since we had established cutting rotations for the sedgebeds (4 years), reedbed (4 years), ditches (5 years) and willow pollards (6 years). We also began to monitor the wildlife on the marsh, producing reports for the EWT on the birds and mammals present. In 1994, we surveyed the sedge plots, which had been cut in the spring, summer and autumn against a winter control plot, in order to gauge its effectiveness in improving the species diversity. We found that the differences in the species composition in each plot owed more to the water level than the management technique. Summer cutting was therefore stopped and substituted by late winter / early spring cutting, since this was felt to be more beneficial to Snipe, which still nested regularly on the marsh in those days.

The most botanically rich part of the reserve has always been the peatbank, 6 acres of M22 (marsh thistle / blunt flowered rush) wet pasture situated on rising ground on the east side of the marsh and standing on 6 feet of waterlogged peat with spring flushes. The flora here includes blunt flowered rush, early and southern marsh orchids, hay rattle, ragged robin and marsh valerian, all species that are distinctly uncommon or rare in Hertfordshire and Essex these days. The peatbank was traditionally managed through cattle grazing. Since becoming a reserve, the peatbank has been mowed annually in late summer / early autumn by Mike Rowley and his Uttlesford District EWT volunteers group. The cut material was raked up and burnt in sometimes spectacularly large smouldering heaps.

However, the act of burning added nutrient to the ground and the old fire sites were plainly visible and were steadily destroying a rare habitat type. When the opportunity arose to have the reserve included in the Higher Level Stewardship (HLS) scheme therefore, I leapt at the chance, since this meant that funding would be made available to fence the whole area and reintroduce cattle grazing – a long held dream of mine! In 2009 / 2010, the whole area was fenced and a small herd of

Highland cattle have grazed there between June and October ever since. The effect they have had is remarkable. Where there were stands of Great Willowherb and meadowsweet, these have been largely eradicated and the whole peatbank looks much more grassy these days, probably as it did when John Dony and John Fielding came to survey the marsh back in 1962.

Although most of the plant species found in 1962 are still present, other species have been lost. The Snipe no longer breeds on the marsh. Turtle dove, Tree Sparrow, Willow Tit and Corn Bunting have also been lost, as have frogs, toads and water voles. It is not all bad news however. Frogs have recently returned to the marsh and Otters have been seen nearby. Water Voles are

soon to be reintroduced to the upper Stort valley and should hopefully find their own way back to the marsh in time. We also have recent arrivals like the male Cetti’s warbler that has been entertaining us with his loud but brief bursts of song and formerly persecuted species such as the Raven, Buzzard and Polecat have also been seen on and around the reserve. Who knows what the next 25 years will bring?