Woodland Management for Conservation
In Britain ancient Woodlands are recognised as the most important for nature conservation. Certainly in the South West we have our rare and important Atlantic Woodland habitat to preserve. The charity Plantlife’s own ‘Building resilience in South West Woodland‘ project has been an invaluable resource to our work in woodland management.
Secondary woodlands offer a structural complexity too, establishing a different formation of vegetation which can develop into rich habitats.
As woodland managers we must embrace every opportunity to diversify secondary woodland. Our British landscape will be enriched by establishing more than just 11% under trees.
Woodland Habitat & Management Methods
The management methods depend on the woodland habitat, ecosystem, geology and its previous uses. Our objectives differ between ancient and secondary and whether a single woodland or group. We also need to consider the open spaces within and surrounding influences.
Here is an outline of woodland habitats & and basic methods of intervention. We’ve also highlighted where we have used these prescriptions with our own woodland biodiversity improvement plan. We also have case studies available for the work we’ve done for our clients.
Coppice. Its ecological value.
Coppicing produces a light environment similar to that of a young natural forest or from a gap created when a mature tree falls. In the early stages of a coppice cycle the ground flora is rich and butterflies abundant. Along with the increased light, temperature to the ground is higher and moisture in the soil lower.
Animals such as Dormice thrive in coppice management as they feed on nuts, berries and invertebrates. Periods of coppicing are important to note. For example, hazel takes around 8 years to produce nuts, therefore a coppice rotation would need to be 15-20 years.
Our own Sessile Oak woodland is an ancient woodland that has been coppiced, potentially for as long as a few hundred years. We know it was harvested to produce charcoal for the local gunpowder mill but neglected for many decades.
As a small woodland and derelict coppice, we have opted out of this method of future management as a whole, instead we want to manage it as a future natural forest. We are therefore coppicing many individual trees to make room for those with the best potential for crown improvement and a long life. Basically a patchy coppice and subsequent singling of trees to create a less uniform structure to the woodland.
We are also involved with our neighbouring woodland management and will be coppicing a section in winter 2021 and therefore the whole area will benefit from different management techniques.
Management of ancient woodlands/old growth forests require less intervention, allowing dead wood to accumulate and a natural woodland structure to form. Where trees die and fall naturally, not only does this create openings in the canopy for regeneration, but the dead wood generates suitable habitat for fungi, lichens, bryophytes, invertebrates and associated fauna such as birds and bats.
In England there is less than 800,000 acres remaining of ancient woodland.
In these woodlands, dominant species can require intervention, such as holly in the understory or beech can often take over being so shade tolerant. Self seeding sycamore can also be a problem in those openings. Maintenance includes the monitoring of glades/rides and thinning those less desirable immature trees.
Britain has no virgin Forest, so a woodland can be chosen for how appropriate it is to have minimal intervention. Ideally large mature key species and veteran tree habitat. The process is very slow so initial management can accelerate the patchiness and dead wood elements for the future health of the woodland.
We have chosen our woodland due to its ancient designation. We wanted a woodland requiring our attention to improve it. Although its smaller than one would want in such a project, we want its future to be as similar to a natural woodland as much as it’s viably posible. Careful consideration has been made over the work we carry out, to help develop valuable habitat for species dependent on mature trees and to increase its biodiversity. We also need to consider that even large woodlands will be influenced by their surroundings such as pesticides, , agricultural runoff, invasion of edge species and air pollution. Not forgetting Britain has lost many of our large mammals.
The biggest benefit to us as woodland owners, are the long term educational opportunities a project like this has provided. It has formed a baseline for monitoring environmental changes. We are documenting and sharing our progress whilst studying the natural dynamics of the woodland. We are wanting to create the wilderness atmosphere missing from our environment as a whole.
High forest is woodland that has a closed canopy (unlike coppice or old growth woodland) and has far less biodiversity. It is usually under some form of management for timber production rather than conservation and therefore: same aged, one or few species, a lack of shrub layer, dark throughout and dead wood is often removed.
Occasionally these woods are managed for recreational benefits. Management can therefore incorporate techniques to enhance biodiversity. Such as:-
- Encouraging natural regeneration of native tree species.
- Creating a diverse age structure and good shrub layer through planting and regeneration.
- Protecting some of the large mature trees
- Retaining standing and fallen dead wood.
- Removing invasive species such as Rhododendron.
- Managing other habitats such as tracks, glades and streams.
- Ensuring that forestry operations have minimum negative impact.
Some of our oldest trees are situated sporadically throughout our parks, estates, grazed common land, royal forests and medieval deer parks.
On these sites, stopping or even relaxing grazing can be very damaging to the epiphyte community of such old woodland sites, as well as certain bird species who do not do so well in dense undergrowth.
Pollarding has been very successful in producing many of the magnificent ancient Beeches and Oaks in lowland wood pasture which are rich in Epiphytes and saproxylic communities.
It is desirable to continue the pollarding tradition on young or middle-aged trees which benefit from an unshaded environment. Prolonging the life of the tree for future generations and woodland communities to benefit.
Shrub and sub canopy management
The opening up of our canopy will assist the development of the shrub and sub canopy, through regeneration and will increase the age diversity. The light created through thinning, coppicing and ring barking is also allowing us to plant flowing, berry producing shrubs.
To add food and shelter for birds and pollinators, we have group planted silver birch, a few downy birch in the wet woodland and planted occasional mountain ash throughout. We have added a few crab apples and a group of small leaved lime. Shade tolerant Guelder Rose has been introduced and spindle has been added to the woodland hedges.
Rides can be managed by crown raising, coppicing and veteranisation techniques to imitate damage and benefit wildlife habitat.
In our woodland we have cut back the oak and holly to widen the rides (they should be to 1.5 x the height of the trees but a small woodland doesn’t permit this width). The bordering regrowth will be cut every 4 to 7 years.
Glades will be monitored for regrowth of less desirable trees such as sycamore and the bramble managed in those light patches to allow for our seed bank to show its true colours. We do expect to see a great deal of oak regeneration this year due to the mast year of acorns we had in Autumn 2020
Wet Woodland, Marsh and Stream
Our wet woodland consists of willow/alder carr and has become a rare habitat. Through some natural fallen trees and some management of holly and hazel over the marsh and stream we have patchy lighter areas which are without doubt the most beautiful where flowering is abundant. Under the darker willow growth, much of our wild wetland flowers do not flower so well but we have been advised by a local ecologist to let it be. A lot of the marsh is dominated by Hemlock Water Dropwort and some areas of dense nettle. We are managing patchy areas for diversity reasons. It will be dug out according to the Centre of Ecology and Hydrology and disposed of by drying and burning.
We have identified many other wetland species and the reduction of dominating species, will enhance this floral habitat where insects and birds benefit from the open canopy next to the stream. We have started digging a pond complex and observing the benefits of new species, including dragonflies for the first time in our woodland. This work continues as per our 3 year woodland plan, along with exciting wildlife installations such as an otter holt to come.
We have also considered the possibility of agricultural run off being the cause of nettles and Hemlock Water Dropwort, we have tested our soil & water and are seeking further advice from organisations such as the Westcountry Rivers Trust.
Our species list is a consistent tool to monitor the changes in our woodland. This also helps us identify food plants to study the lifecycle of our wildlife that rely upon them.