Woodland Management for Biodiversity

Woodland Management for Biodiversity

A woodland acts as a reserve for the whole landscape, linking a network of habitats. Vast amounts of Cornwall’s landscape are arable and pastoral with woodlands often isolated. Over time our environment has lost species with limited mobility that have been unable to recolonise. Therefore woodland management should aim to sustain all species present and enhance the ability for indigenous species to thrive and regenerate. The flora of ancient woodland, particularly coppices tend to be richer than more recently planted woodland. However, a neglected woodland can decrease diversity after the canopy closes, becomes compact or one or few species of tree takes over and dominates the landscape. Woodlands can often consist of too many similar age trees and height and can subsequently become etiolated. They can also lack an understory & shrub layer or alternatively suffer from dense stands of holly, rhododendron or laurel offering little diversity. 

The management plan for our own woodland is not to sustain a timber supply, but for the sustainability of a species rich environment. (although excess timber, post deadwood retention will be of benefit for crafts and shelter building),

These techniques include:

  • Woodland thinning.
  • Coppicing.
  • Veteranisation techniques.
  • Ring-barking.
  • Pollarding
  • Planting of native tree and shrub species.
  • Ride, glade and watercourse management.

We consider the following woodland communities within our own management plan…

Tree Communities

Genetically many trees within an ancient woodland will be direct descendants of those in the original forest. Our aim is to maintain and improve age diversity with the original community of trees by natural regeneration. In our biodiversity improvement plan for our ancient but neglected oak coppice, this can prove impractical, so we have planted some local provenance trees for the benefit of biodiversity. This includes shrubs for our borders, ensuring flowers and fruits are abundant throughout the seasons.

The many oaks in our woodland require space and light, they are thin, tall with small crowns. We selected at least 2 in 5 trees to be thinned in year 1 & 2 and opening up other areas for regeneration. We are retaining trees with good crown potential and ones that show great benefit to associated wildlife. Decisions where further thinning was required has been made in year 2 and underway. A few trees such as our larger sycamores have been ring-barked, creating more standing deadwood of larger diameter.

Ground Flora

We are thinning the woodland and creating openings for the light to penetrate the ground. Hoping the seed bank regenerates with more species currently absent and our current woodland plants have more luxuriant growth and longer flowering periods. We are concerned by agricultural run off that may be affecting our soil with too much inorganic nitrogen. This is not yet proven but being monitored post our canopy management.

We have also sought information to manage the dominant Hemlock Water Dropwort in our marsh area. We will be manually or mechanically digging it out in June 2020 according to techniques from the Centre for Ecology and Hydrology.

Epiphytic Flora and Fungi

This community relies on a number of woodland attributes: This can be shade for the bryophytes, light for the lichens, decaying wood for fungi and moisture for all. We are lucky to be in the “wet” South West where epiphytic communities thrive in our unpolluted atmosphere. We also benefit from the important Atlantic Woodland flora specific to the West of England’s temperate rainforest. Angie has trained as a Bryophyte botanist as well as attending numerous Lichen/Atlantic woodland courses to ensure we embrace our micro habitats within our holistic approach to woodland management. Nigel has the experience in our tree fungi as well as pests and diseases, whilst ground and deadwood fungi remain an ongoing interest of us both.

Saproxylic Invertebrates

This community depends on dead or dying wood. We prioritise dead wood within any woodland habitat, we leave most of our felled oaks where they fall and never fell standing deadwood. We have recently ringbarked some of our larger sycamores to gain bigger diameter standing deadwood than our woodland currently offers. This also gains light in those areas for regeneration of our native trees and ground flora. The thinning of our compact and overpopulated oak, gives us more ground deadwood to replace some of the already very decayed wood on the ground. Whilst some are left where they fall, we use others to border trails and make shelter. Oak being long lasting and no treatment needed, it allows the structures to eventually decay like any other deadwood.

Butterflies

Most species of woodland butterflies live in the open areas of rides and glades. In small woodlands, It is unrealistic to consider anything more than a large ride or small glade/opening. We are maintaining our ride and creating openings for regeneration. In approx. 5 years when this regrowth is established, we will consider the location of the next opening.

We have observed a large adult population of Silver-washed fritillary in our woodland. They appear out of the leaf litter in mid-summer and feed on the nectar of our bramble. Careful consideration needs to be taken in summer to ensure the foot fall stays in areas where they are not resting in abundance and we do not strim at this time of year.

Mammals

Unlike most management plans which mainly consider the habitat for dormice, red squirrels and bats, we consider the safe environment for our larger and predatory mammals as well. A woodland is their main habitat and mammals are an important part of the ecosystem. We should ensure populations remain healthy and the environment enriched with food.

A great deal of woodland wildlife is managed and hunted, including deer, badgers, foxes, rabbits and squirrels. I appreciate populations are successful, however:

Our woodland which we manage for wildlife, does not suffer from an excessive or destructive population of any particular species.

  • Our Roe Deer do browse but not yet proven to be to the detriment of regrowth. We are protecting some saplings and newly planted trees to be entirely confident. We have several resident deer families, often seen in our cameras where we have observed fawns grow from 1 day old through to them parting with their mothers. It’s a pleasure watching their affection for each other and the fun the young deer have.
  • Grey Squirrels like red squirrels do cause damage, but for our woodland which is not managed for timber, the current amount of damage caused is beneficial for other wildlife such as bats and woodpecker’s to thrive. We know of no introduction plan for reds in the area and the isolated nature of our broadleaved woodlands is not suitable habitat. We believe reds will not gain a stronghold in our current local landscape. Whether Idless woods could support them is a matter we have not yet been informed about.
  • Our badgers as in any woodland, are at the peril of the surrounding farmland if they choose to cull. To understand the problem and right solution to eradicate TB in cattle, Angie trained as a badger vaccinator with the APHA. Before our ownership, good populations of badgers lived in the numerous big setts but most of the setts were inactive before we took it over. Potentially due to an air rifle target practice occasionally held before we purchased. However, badgers currently use our woodland as a large part of their habitat. We monitor badgers at their runs and latrines and use peanuts on occasions as an encouragement tool. We welcome them back as full residents.
  • Foxes are resident and use old badger setts. We have witnessed offspring in 2019/20. Another mammal important for a thriving healthy ecosystem. We are communicating with the hunt that use the area to ensure they know in no uncertain terms; they are not permitted in our woodland.
  • We have recorded Pipistrelle Bats in the woodland but a local ecologist has suggested that Brown Long-eared bats are present in the area. We carefully select trees that do not make good habitat for bats when thinning. We have installed 8 bat boxes and purchased an echo meter touch 2 to allow us to monitor activity. We will, if and when required, seek advice from expert ecologists in this field.
  • We have not yet observed any signs of dormice and our shrub habitat in not currently ideal. We have also been informed that they have not been recorded in this area of Cornwall for many years. Our small area of Hazel will be coppiced over the coming three years and we will observe information of any potential re introduction in the area.
  • Our rabbits are not a large population, all appear healthy and we protect planted shrubs with rabbit guards.
  • We have only witnessed a couple of Stoats near the marsh. We don’t yet know if they are resident but our stream banks offer good habitat.

Birds

Managing the layers and age structure of a woodland is a priority when considering healthy bird populations and species diversity. Our woodland has both upper Oak woodland and wet woodland which is encouraging for a range of species. However, with a predominantly Oak and holly woodland and a limited shrub layer, we are currently introducing/planting a range of other native tree and shrub species whilst opening up the canopy. These species will enhance the flowering period and autumn berries for winter feeding birds. We have also been asked to retain the Willow/Alder carr as it currently stands, to encourage the Pied Fly Catcher.

Many of our birds are observed through the song above, using our nest boxes and on our bird feeders. We have installed 10 bird boxes and a Tawny Owl box and observed Buzzards nesting high up in the canopy whilst watching the chicks grow up. We have good populations of Blackbird, Song Thrush, Nuthatches, several species of tits & finches, along with Redwing visitors in January. We have also found some of the beautifully constructed long tailed tit nests in the far area of the woods. Our lager birds include Woodpeckers, Jays, Jackdaw, nesting Buzzards and at least one breeding pair of Tawny Owls. 

Check out our species list for the woodland here: Happy Habitats Woodland Species List

* We appreciate that badgers have protection, but the damage caused by the cull far outweighs the benefit of this protection. 

About the author: Angie Cruse

As well as working hard on the ground here in the UK, Angie has spent ample time volunteering in conservation abroad and continually studies habitat management in conservation.