Peatlands

To discover what truly shapes the Weald Moors wetland heritage, it’s necessary to look no further than the soil beneath our feet. The area’s naturally wet, poorly draining and seasonally waterlogged peatlands have been largely responsible for determining the range of wildlife to be found here for thousands of years…

Glacial Origins: to uncover the Weald Moors peatland origins we must go back twenty thousand years to the end of the last Ice Age. At that time, a number of glacial lakes began to drain, leaving a distinctive pattern of ridges and hollows that defined the character of a landscape better known to us as the ‘Meres and Mosses’ of north Shropshire. While sharing their origins, the Weald Moors are something of an anomaly because they are neither of these things but, rather, an ancient and extensive low-lying peatland laid out along the course of the River Strine and its tributaries

A Peat Fenland Is Born! Central to the process of peat formation is the presence of water and, more specifically, waterlogging. Nowadays, there is a complex system of artificial drains to manage the Weald Moors high water table but in distant times dead plant matter that settled in the area’s slow-moving channels had nowhere else to go, so simply built-up and decomposed in situ. Areas of ground that receive or collect (rather than shed) water are usually defined as fens and so it was on the Weald Moors, which still act as a sink for much of the surrounding area today. Here, the absence of oxygen in the soil caused by the weathering effect of naturally acidic rainfall helped to preserve the semi-decomposed organic matter from which peat is formed, providing us with a living history book of the landscape that, in some instances, is thousands of years thick.

Landscape-Shaping Influences: to say peat accumulation is a tortuously slow process is something of an understatement — it can take up to a year for just one millimetre to form! Where deeper reserves persist, however, peat soils have much to tell us, and this is certainly true on the Weald Moors. The recovery of pollen grains and insect remains trapped deep within the remaining moorland peats have allowed us build up a picture of the local landscape stretching back some seven thousand years ago. At that time, the area was a watery fenland comprising vast beds of sedges and tall grasses rooted in shallow peats, surrounded by scattered alder woodland. This seems to have been the case until at least Roman times.

This ancient picture also says something much more elemental about the value of the Weald Moors naturally wet, acidic peat soils and their ability to influence the plant life that defines so much of the area’s wetland character — which is equally true for the many specialist insects, birds and small mammals that rely upon its moisture retaining ability to meet their need for food, nutrition and water. Yet, while the Weald Moors peatlands have played a starring role in establishing the area’s wetland credentials over many millennia, their continued ability to provide for the needs of its characteristic wildlife is much less certain…

A Vanishing Landscape? A trip around the modern day Weald Moors reveals a picture of a disconnected landscape, with little obvious sign of its fenland origins to be found in many parts of the locality. Although this is no longer an active peat-forming landscape (lacking, as it does, the correct wetland vegetation to build on its existing resources) there are still a number of places where thick reserves in excess of one metre remain. Sadly, there are also many other locations where the Weald Moors peatlands have been depleted to the extent that they have vanished completely or appear very likely to within a few generations.

Peatland is the largest semi-natural resource in the UK but, like the Weald Moors reserves, much of it is inactive and exists in a degraded state. Peat soils are highly absorbent but water movement within them is extremely slow — one raindrop, for instance, might take up to ninety years to filter through ten metres of peat! While this limits the drying properties of individual drains to a very limited area, their very presence enables water stored within existing deposits to seep away more readily, drawing down the water table and causing peat to dry out, shrink and subside. In an area with an elaborate, landscape-wide drainage network, the consequences of this process are obvious and have been witnessed for many centuries, both in the widespread wastage of local peat deposits and the physical lowering of the landscape that resulted from it.

On the Weald Moors: some of the deepest and most extensive of the Weald Moors dark peatland soils can be found in the north of the moorlands on Waters Upton and Crudgington moors, and surrounding the ‘island’ settlements of Wall Farm and the Buttery. Even here, the lowering of the land caused by centuries of drainage and abstraction can be seen in the exposed roots of roadside trees and in the undulating nature of the highways themselves — a sure sign of peat wastage beneath. In spring and autumn, the freshly tilled soils of arable fields on Rodway, Sleap and Sidney moors provide a glimpse of another phenomenon known as ‘skirtland’. This term describes the thin, dusty layer of dark organic topsoil that represents the last vestiges of a peat heritage once metres thick.

In these areas, any chance of saving this irreplaceable resource has gone. Aside from the consequent effect on the wetland wildlife that depends on it, there are equally extensive implications for the wider world in stemming further losses. In their natural state, peatlands trap huge amounts of carbon and lock it up for millennia. Another of the long-term effects of drainage is to allow oxygen to penetrate existing reserves, causing the decomposition of the stored organic matter within, which is then released into the atmosphere as carbon. As we have already seen, peat soils are also capable of storing vast amounts of water. The Weald Moors act as a rainwater sink for a large area of east Shropshire, and form a highly valuable source of flood alleviation for many thousands of local residents. This illustrates that, ecological issues aside, there are many sound economic reasons for ensuring the continued existence of our peatlands, too.

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