The importance of our woodlands and forests to nature and the environment
Our trees and woodlands have a direct impact on the environment and climate. They also host flora, fauna and fungi and form an essential part of many Sites of Special Scientific Interest.
Native deciduous woodlands
Deciduous trees are those that shed their leaves in autumn. Woodlands of oak, alder, hazel and ash are common throughout our National Park. Hawthorn and other native species often form an understorey beneath the canopy of larger trees.
Many woodlands are small fragments surrounded by open fields. These are often remnants of much larger woodlands and are very important as they can provide stepping-stones to allow species to move across the countryside. Where woodlands occur on the slopes of gulleys or streams, they may have existed there for hundreds of years as it has never been possible to farm these inaccessible areas.
Almost all the remaining woodlands have seen some management by humans. These woodland areas used to be an essential part of every farm as they provided timber for fences, firewood and other uses. In many cases the management was called coppicing - the practice of cutting down the tree but allowing the stump to grow new shoots. This produced a renewable crop of timber and the timber could be cut when it reached the right size for its intended use. Hazel was most often coppiced and coppice stools of hazel can be found in most woodlands around our National Park.
Large areas of our National Park, particularly in the uplands have been planted with conifers. Plantations of larch, pine and fir have now reached maturity and stand out from the open grass and heathlands.
These trees were planted as a commerical crop often on land considered unproductive for other farming. Unfortunately many of these plantations are on rare habitats such as blanket bogs and heaths. These more natural areas were replaced with rigid rows of conifers not native to Wales.
However, conifer forests do have value to some wildlife that has adpated to these new forests. Red squirrels now depend on conifer forests to survive, mainly because they are unattactive to the introduced Grey squirrels. Several birds of prey such as red kites and goshawks need the tall conifers to make their nests. While the dark and shade under the thick evergreen canopy prevents the growth of many plants, they can contain many species of moss and fungi. This shelter also allows insects, particularly mosquitoes and midges to fly in bad weather and this can be a vital food source for several species of bats.
Where the ground is permanently wet, only those trees that can cope with the water logging survive. Willow and alder are both suited to these conditions and can form a dense woodland canopy over standing water. Wet woodland was previously more extensive in Wales but much has been felled and drained to create farmland along the river valleys.
Wet woodlands are important to a number of species as both animals and plants of woodlands and wetlands can be found here. Wet woodlands often developed when tree seedlings took root in other habitats such as fens and reedbeds. Over time the trees matured and shaded out other plants providing more shelter and cover than open habitats.
Wetlands are most valuable to wildlife when several types of habitat occur together and small patches of wet woodland and scrub are a vital addition to any wetland. As these open habitats like fens and reedbed are valuable in their own right, if it often necessary to control the spread of wet woodland by selective removal of some trees but retaining enough to provide for some species.
As one of the most widespread habitats in Wales, woodlands support a great number of species.
The red wood ant builds large mounds in deciduous woodlands to form the nest for the colony. The ants can be 1cm in length and are canivorous, hunting out other insects. They are only found in a few undisturbed woodland in our National Park and they favour open clearings so that the nest mound can catch the sun and keep the ants warm and active.
The waved carpet moth has recently been found at a site within our National Park for the first time in more than 70 years. The caterpillars of this small moth feeds on alder, birches and willows and can most usually be found in damp, coppiced woodlands.
The lesser spotted woodpecker is the smallest of the three woodpeckers in Wales and also the rarest. Small, quiet and elusive it can be found in the highest parts of the woodland canopy, searching for insects, or softly drumming on a tree.
The spotted flycatcher arrives in the UK in May and can often be found along woodland edges where it waits for passing insects before flying out to take them. Its numbers have reduced dramatically in recent years.