A most interesting article from Eco tree care and Conservation.
Coppicing, Felling & Thinning
Coppicing is an ancient form of sustainable woodland management which makes use of the ability that some trees have to regenerate themselves when they are cut. In this system the tree is cut to ground level in the winter months and then left to regrow. When it reaches a harvestable size it is recut. This continual cutting creates a low cut stump that regenerates, known as a 'Coppice Stool'. The coppice is re-cut on a 'cycle' or 'rotation'. The idea is that woodland areas, known as 'cants' or 'coups' are cut sequentially. The number of these areas being the time in years for the trees to reach a harvestable size so there is always annual produce.
It provides the understorey in a woodland and is a regular and sustainable source of timber when managed properly. The most common trees to be coppiced are hazel, hornbeam, sweet chestnut, oak & willow.
Coppice is a major type of woodland in Britain, which on the whole has unfortunately been left without management since the second world war. The result is that much of our coppice woodland is desperately in need of re-cutting in order to preserve its integrity and maintain its overall health. We are at a stage now where some of the coppiced trees are falling apart and so falling over. As time goes on the ability of overstood stools to regenerate diminishes and often upon cutting they may die completely. The woodland will then require re-stocking.
Coppice when allowed to become 'overstood' has a tendency to fall apart and therefore the quality of the woodland decreases
Bringing coppice back into 'rotation' now may just save such overstood coppice, increasing biodiversity and creating a local sustainable source of wood fuel and timber
Coppicing is also important for biodiversity in woodlands as the system means that there is a range of different tree ages and heights across the whole woodland, with all the diversity of wildlife that comes with this variation.
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Hornbeam Coppice - Hertfordshire | Coppice Produce |
Felling & Thinning
Where trees have been managed for timber the standard activities of felling and thinning are part of the management plan.
Selective felling is undertaken to carefully remove trees ready for timber conversion , we have a Peterson for onsite milling if conversion is required on site. This can help reduce extraction costs and damage. Sometimes it is the only viable option for extracting timber from difficult sites.
Selective felling is also carried out where there is a need to fell for creating clearings or ponds, or for health and safety reasons.
Thinning - When woodlands are planted the young trees are closely planted so they compete with each other and 'draw' each other up towards the light. This encourages straight growth. As the trees grow older thinning takes place periodically. The purpose is to selectively remove poor specimen trees and/or to give more space and light to those with a greater potential to grow into fine mature trees.
The amount of thinning must be carefully considered. Over-thinning can lead to the phenomena of 'Windthrow'. Trees as they grow seek to equalise the stresses and strains across the whole of their structure, only putting on extra woody growth in the areas required to 'engineer' a strong a stable structure. Where trees have grown up together they shield and buffer each other from their environment, collectively they are strong, individualy they are relatively weak. The act of woodland thinning removes neighbouring trees from around the trees to remain, therefore for a time these remaining trees are vulnerable to gusts of wind that can 'get into' the stand of trees. If the wind does get into a stand of thinned trees and starts to blow over vulnerable trees then effectively more trees are being thinnned and the result can be a 'Domino effect'. A lot of value can be lost if this occurs. Apart from our expeirience and knowledge of tree growth, we will also consider the topography of the location and the prevailing wind direction. Decisions can then be taken to thin less in some areas and thin more in others accordingly.
Clearing Rhododendron, Sycamore & Laurel
Invasive non-native species such as Rhododendron, Sycamore & laurel can become a challenge in any woodland if they are left to grow unchecked.
Where shooting has recently been the main use of a woodlands, Rhododendron and Laurel were often planted to give cover to game birds bred in the woods . Or it may be that they have 'escaped' from nearby planted ornamental gardens. Whatever the case they can develop into a major problem with the eventual result in some cases being that the woodland becomes pure Rhododendron or heavily dominated by laurel.
Sycamore is adept at setting seed and in some woodlands can develop to become invasive casting a deep shade under which few other species stand a chance.
Rhododendron
Rhododendron, although a beautiful flowering tree, becomes quickly invasive.
It self-seeds and propagates by lateral branches spreading out and rooting. Rhododendron spreads out covering the ground with a deep dark shade under which nothing else can grow. The break down of its leaves acidifies the soil as it goes. In some cases removal of Rhododendron is something that can only be achieved by consistent effort over many years, especially if it has already become well established. There are woodland improvement grants available from the Forestry Commission to remove Rhododendron from woodlands, which is something worth looking into. It is definitely worth investing the effort to remove it in woodlands where nature conservation is the main aim.
Rhododendron is also a vector species for the Phytophora 'Sudden Oak Death/Bleeding Canker'fungus. On the positive side Rhododendron makes excellent firewood and charcoal. It burns at a high temperature.
Sycamore
Sycamore is a technically non-native, however it has been on the British Mainland for many hundreds of years. Some consider it naturalised or as good enough native, it just depends how far you go a back in time. Sycamore does support a certain amount of wildlife and can be an important timber crop. When mature in a parkland setting they are magnificant trees.
However, Sycamore seeds prolifically and these seeds self-set very easily. This means that in some situations it can become an invasive species.
In woodlands when establishing under favourable conditions it can become over dominant.
A characterisic of Sycamore is that it develops large leaves which can out shade other species, it also shade tolerant itself and grows quickly.
It coppices easily and so even cut stumps need to be treated or removed in order to prevent re-growth. Small 1-2 year old seedlings can be hand-pulled, but after this they require cutting and treatment.
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