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SITE VISIT TO TOLL WOOD, LYNSTEAD, KENT - FEBRUARY 2001.
Barry O' Dowd.
Toll Wood stands on the gradually rising northern slope of the North Downs, just to the south- east of Lynstead. It is a linear woodland running north - south, some 400m long and averaging 130m in width - appx 6 ha. It slopes westwards into a shallow dry valley and is bounded to the east by a narrow road - Toll Lane. The wood is an important natural feature in the landscape where the nearest significant woodland is a mile to the south.
Ecology
As far as we know Toll Wood stands on a thin layer of clay overlying the chalk and contains four distinct habitats: the tall forest, the northern alkaline or chalky grassland, the scrub surrounding the grassland, and the western cut ('coppiced') edge.
Tall forest
The southern 2/3rd's of the wood is generally uniform in terms of structure and tree age. The trees are tall and generally even aged, most are close standing reflecting secondary growth following clearance some time in the past. The dominant tree is Sycamore Acer Pseudoplatenous, a long- standing introduced species to the UK which is invasive and casts a heavy shade. This species tends to exclude native tree regeneration and produces copious quantities of seed, so spreads rapidly, eventually dominating the canopy, as it has here. Sycamore supports very few insect species though abundant quantities of aphids feed on its leaf sap and are an important bird food. Some trees are multi- stemmed indicating localised coppicing/ tree felling in the past.
There are a small range of native trees present in the tall woodland including many fine Hornbeams Carpinus betulus and some Beech Fagus sylvaticus both of which appear to predate the Sycamore thus indicating a long-standing history of trees/ woodland on at least part of the site. There are also some huge tall Wild Cherry Prunus avium trees though no younger trees were seen. One or two Field maple Acer campestre occur with lots of young Ash Fraxinus excelsior along the western edge. The history of woodland on this site is not known, a ground flora study in the summer should determine if it is an ancient woodland site or not. There is evidence of old wood banks in the wood which were historically constructed to mark ownership and wood boundaries.
Of greater interest is the northern third of the tall forest which has extensive elm Ulnus stands, specific species yet not determined. There are a number of tall fine trees which are not apparently suffering from Dutch elm disease. From these there are younger suckers forming extensive stands. These trees have extended into the grassland at the northern end of the wood but are being superseded by elder scrub and sycamore invasion into the alkaline grassland. This is undesirable as the open grassland is probably of significant conservation interest (see below).
The northern third of the wood has some induced structural diversity and also dead wood (biologically valuable) as a result of the 1987 storm. Many trees, especially hornbeam, were blown down and most have re-grown in their prone position. Light penetrating the lost canopy is encouraging shrub and herb growth. The shrub layer within these gaps consists largely of Elder Sambucus niger. Otherwise there is little shrub cover within the wood apart from some hawthorn in localised areas, especially where there once existed a broad track through the wood. The ground flora could not be surveyed at this time of year although dogs mercury is abundant and there are small areas of bluebells which may indicate ancient origins.
The northern alkaline grassland
This area of only 3 or 4 acres may be the richest part of Toll wood in terms of uncommon and valuable species. The substrate of the area needs further examination but probably consists of a thin layer of clay over the chalk which forms the North Downs. This would produce an alkaline soil, chalky clay in simple terms. Chalk grassland is highly localised in the UK and good examples contain some of the richest plant communities found in the British isles. Orchids are likely to occur and the range of nectar- rich plants throughout the summer should support a colourful range of butterflies and rare invertebrates. There was not time to look closely at the grassland and a further trip in the spring/ summer is necessary to see what is there. If of high value the sward may require grazing management to optimise its richness, it seems that rabbits are presently doing a reasonable job.
Unfortunately the sycamores are seeding into the grassland with mixed scrub spreading in from the woodland and perimeter hedges. The removal of some invading trees and scrub would help restore the grassland which is being lost. Further surveying is required to determine the exact value of this area and recommended management.
Scrub surrounding the grassland
A hedge borders the eastern edge of the wood (along the roadside) where there is much hazel Corylus avellana. The hedge continues around to form the northern perimeter and north-west section surrounding the grassland. Here there are hazels, though blackthorn Prunus spinosa is the most common hedge constituent surrounding the grassland. The hedges here are tall and largely unmanaged and spreading as suckers and seedlings (especially hawthorn) into the grassland. The hedge and scrub forms a rich habitat in its own right and a natural border between the 'natural' grassland of Toll Wood and the surrounding orchards and improved sheep pasture.
The gradation from grassland into scrub forms a rich invertebrate habitat and fine bird habitat which is certain to provide prime habitat for breeding songbirds, especially warblers, in the summer and residents such as the Long tailed tit and the declining Bullfinch all year. As mentioned earlier the scrub may require management to maximise its value and maintain some open grassland.
The western cut or 'coppiced' edge.
Telegraph/ electric wires run along the western edge of the wood and the shrubs/ trees below are cut close to ground level every few years (maybe 3-6yrs). This 'coppiced strip is probably flailed and does provide a species-rich shrub strip which is dense and was about 4 -6 feet tall at the time of the visit. Dogwood, spindle, privet and travellers joy are all common here, a rich nectar source for invertebrates which will be warmed by afternoon sun in the summer months. This long dense strip should provide good feeding and nesting sites for birds in the summer and provide autumn fruits also.
Birds of interest recorded on the visit:
Long-tailed tits, Mistle thrush, Song Thrush, Redwing, Sparrowhawk, Goldfinch, Bullfinch.
Barry O' Dowd, Elmley RSPB reserve, Sheerness, Kent. ME12 3RW.
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