Lower Wood: the changing face of an ancient woodland

Fresh snow in Lower Wood, Ashwellthorpe, February 2012. Photo by S. Shailes. CC BY 4.0

Fresh snow in Lower Wood, Ashwellthorpe, February 2012. Photo by S. Shailes. CC BY 4.0

Lower Wood in Ashwellthorpe is one of the few remaining ancient woodlands in Norfolk. Today, the wood is about 100 acres in size, which is only a small remnant of its recorded size in the Domesday Book of 1086. Having been managed for centuries to produce wood for local industry, the last 50 years have seen the wood undergo many changes and face new challenges.

The wood was managed by coppicing to produce wood for a variety of purposes including charcoal production, fencing and furniture. It also supplied the local brush-making industry, which by the end of the 1700s was thriving in Norfolk (1). From 1922, the wood supplied the Co-operative Wholesale Society Brushworks in the nearby town of Wymondham, which in its heyday employed over 200 people. However, by 1983, the brushworks was unable to compete with cheap imports from abroad and it closed (1). Coppicing stopped in Lower Wood sometime in the 1970s and without it, the canopy of the wood became denser and biodiversity suffered as less shade tolerant plant species struggled to survive.

In 1973, Lower Wood was given a Site of Special Scientific Interest (SSSI) notification (2) because it is an ancient woodland where most of the coppice trees are plateau-alder (Alnus glutinosa), which is rare in the UK. Other tree species include hazel (Corylus avellana), field maple (Acer campestre) and sallow (Salix caprea). It was traditional to leave some trees in a coppice uncut for longer periods to produce wood with a larger diameter — called timber — to use for building or shipbuilding and, in Lower Wood, these so-called “standards” are mostly oak (Quercus robur), ash (Fraxinus excelsior) and hornbeam (Carpinus betula).

Early purple orchids growing near a coppice stool (top left). Common twayblade in flower (bottom left). A white admiral butterfly (right). Photos taken in Lower Wood by Anne Edwards.

Early purple orchids growing near a coppice stool (top left). Herb paris in flower (bottom left). A white admiral butterfly (right). Photos taken in Lower Wood by Anne Edwards.

The wood is also unusual in that it lies on a boulder clay plateau and the chalk in the clay promotes very diverse ground plants including uncommon species such as ramsons (Allium ursinum), early purple orchid (Orchis mascula), herb paris (Paris quadrifolia) and common twayblade (Listera ovate) (2). The plants in turn support interesting wildlife and the site is home to the rare white admiral butterfly (Limenitis camilla), which exclusively lays its eggs in honeysuckle (Lonicera periclymenum), a climbing vine-like plant.

Despite becoming a SSSI, the wood was neglected until the Norfolk Wildlife Trust (NWT) purchased it and started restoration coppicing in 1992. The first round of coppicing was especially tough because, due to the long gap in management, the trees had produced wood that was much larger in diameter than would be produced from a normal coppice cycle. The NWT coppice the wood to conserve it, not for the wood it produces, so the cutting season is restricted to October-March to prevent trampling of wildflowers or disturbing bird nests. Also, some of the cut wood is left to decompose to support fungi and insects. Newly coppiced areas are surrounded by electric fences for the first few years after cutting as they are very vulnerable to damage by grazing deer. This is becoming an increasing problem in the UK as deer numbers rise to due to the lack of natural predators.

By 2012, a regular coppice rotation of about 14 years had been established and the woodland was recovering. However, in the Autumn, there was some alarming news: ash dieback disease had been spotted in the wood, the first recorded outbreak in the UK that was not linked to imported saplings in a plant nursery. Ash dieback is caused by a fungus called Hymenoscyphus pseudoalbidusalso known as Chalara fraxinea. There is no treatment for the disease, which eventually kills the host tree, and since then it has spread across the country.

Young tree infected with the fungus. A small necrotic (dead tissue) spot is visible on the stem

Young tree infected with the fungus Hymenoscyphus pseudoalbidus. A necrotic (dead tissue) spot is visible on the stem. Photo credit: Anne Edwards

In Lower Wood, the disease has spread very quickly. Dr Anne Edwards, who leads a group of coppicing volunteers in the wood said: “many of the coppiced ash and seedlings have died already. Several of the standards are also show clear signs of the disease.”

The death of ash trees in the wood is leaving gaps in the canopy, so how will this affect the rest of the flora? Anne says: “bramble will probably run rampant. There are signs of other tree seedlings coming through in the [coppice] block we are [working] in now: hornbeam—quite slow growing so usually out competed by ash seedlings—spindle, hawthorn, field maple. We are “layering” hazel shoots into areas where the ash coppice has died to try and fill in the gaps. If we can keep the deer out, the mixed tree seedlings and hazel might stand a chance.”

There is hope that at least some of the ash trees will survive the disease and the woodland will recover in time. “The [ash] coppice does seem to be showing a range of sensitivities to the fungus, so in some trunks the fungus seems to move very rapidly, in others, progress is much slower. We have tagged any that, at this early stage, appear to show some tolerance.”

Since Lower wood contains trees of many species, ash dieback disease will not destroy the woodland, but it is dramatically altering the mix of trees found there. It is not yet clear what impact this will have on the other plants and wildlife in the wood in the long term, only time will tell.

For more information about ash dieback disease and some of the research that is underway to understand more about the disease please follow these links:

OpenAshDieback: A hub for crowdsourcing information and genomic resources for Ash Dieback

Nornex: a network of scientists from eleven research institutions aiming to make tools to help understand how to deal with ash dieback

AshTag: you can help to identify diseased trees and monitor their health.

Read more articles about woodlands in Focus on… Woodlands:past, present and future

Author’s note: It does not snow in Norfolk often, so the photo at the top of the article is not an accurate reflection of what the wood usually looks like in winter. However, I decided to include it  because it was taken on one of my favourite visits to the wood (and it is almost Christmas!)

References:

  1. Manning, I.M. (1983) The Co-operative Wholesale Society Brushworks, Wymondham Journal of Norfolk Industrial Archaeology Society Vol. 3 (1981-85) p 169.2
  2. SSSI notification: Lower Wood, Ashwellthorpe (1973, 1983)
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6 thoughts on “Lower Wood: the changing face of an ancient woodland

  1. Pingback: Morsels For The Mind – 19/12/2014 › Six Incredible Things Before Breakfast

  2. Pingback: Book review: The Ash Tree by Oliver Rackham | Plant Scientist

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