The Caledonian Forest!
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Native Forest in the Highlands ! - the Caledonian Forest! Alan Watson Featherstone" Executive Director, Trees for Life" Forestry in the Highlands Conference What is (or was) the Caledonian Forest?! Forestry in the Highlands Conference What is (or was) the Caledonian Forest?! A massive expanse of dense pinewood…? Forestry in the Highlands Conference What is (or was) the Caledonian Forest?! …of which only a few scattered derelict remnants survive? Forestry in the Highlands Conference Changing perspectives on the forest! "A variety of woodland types within * the forest – not just pines "" " "Greater component of broadleaved * trees" " * "Varied age structure" " * "The forest is a whole community, of fungi, plants, insects, birds & animals" "" * "The forest is dynamic, changing over time, and from area to area" Forestry in the Highlands Conference A range of woodland types in the forest! The Atlantic oakwoods, such as this in Ariundle Away from the west coast, narrow gorges with NNR, are a bryophyte-rich temperate rainforest cascading rivers, such as this is Glen Moriston, component of the Caledonian Forest! create similar a rainforest micro-climate! Forestry in the Highlands Conference Riparian and floodplain woodlands! Alder and birches in riparian woodland along Alder trees in the floodplain of the! a burn in Glen Affric! River Moriston! Forestry in the Highlands Conference Treeline and montane scrub communities! Krummholz pines and juniper at ! Reindeer lichen, juniper & birches at 500 Creag Fiaclach in the Cairngorms! metres on an island on the Hilton Estate! Forestry in the Highlands Conference Bog woodland and clearings in the forest! This natural clearing in the forest at Dundreggan is formed by an area of boggy ground, which is the habitat for the strawberry spider (Araneus alsine)! Stunted pine in an area of bog woodland ! in Glen Affric! Forestry in the Highlands Conference Diversity of tree species in the Forest! Oak and hazel growing amongst pine and birch Aspens in autumn in Glen Affric. Aspen at the eastern end of Glen Affric. The vegetation would have been more abundant in the past, community here is an upland oakwood one, but its restricted seed production limits its although the forest is mainly birch today! ability to recolonise sites where it is absent ! Forestry in the Highlands Conference Diversity of tree species in the forest! Wych elm growing on a rocky crag ! Ash trees in Rassal Ashwood NNR – a in Glen Strathfarrar! limestone area in Wester Ross! Forestry in the Highlands Conference Diversity of species in the forest! Twinflower grows in abundance in similar forests Zoned tooth fungi (Hydnellum concrescens). The in Scandinavia & North America, but is very tooth fungi are an unusual group of fungi scarce in Scotland – due to past deforestation?! associated with ancient woodland in Scotland! Forestry in the Highlands Conference Diversity of species in the forest! This sawfly (Nematus pseudodispar), a rare boreal The capercaillie has already been extirpated once birchwood species, was only known from Finland from Scotland. Despite much conservation effort, its & Latvia until its discovery on Dundreggan in 2010! numbers are declining and it is at risk again! Forestry in the Highlands Conference Much of the Highlands remains in a depleted condition! Native forest cover still a small percentage of * its former area.! Populations of many species (eg wildcat, wood * ants) fragmented and greatly reduced.! * Important species are extirpated, including keystone species (eg European beaver) and large carnivores.! Crucial ecological processes (eg succession, * disturbance, predation) are not functioning. ! Human pressures maintain the land in a * condition of impoverishment, through overgrazing, muirburn, waterlogging of Deforested riparian area, unable ! soils, export of sheep and deer carcasses etc.! to regenerate, in Glen Affric! Forestry in the Highlands Conference Many areas are in a state of arrested succession! Arrested succession occurs when the natural process of succession from one vegetation community to another is prevented. " Here, at the fence by the road on Dundreggan, heather is flourishing and a birch is growing in the absence of overgrazing. On the other side of the fence, arrested succession predominates and Peat hags are an example of heather (and new trees) are unable to grow. ! arrested succession, where mire vegetation is unable to grow and cover the exposed peat.! Forestry in the ! Highlands Conference Protection from overgrazing allows succession to occur again! At Athnamulloch in Glen Affric, heather and At Allt Coire Ghaidheil on West Affric, the bog myrtle are flourishing inside the fence, protection provided by the fence is enabling whereas outside, vegetation is still unable to the process of succession from grassland to ! colonise the peat hags.! dry heath to occur.! Forestry in the Highlands Conference The role of natural disturbance! Natural disturbance is caused by events * such as flooding, windthrow, avalanches, fire, actions of predators, * insect outbreaks etc.! Disturbance operates at all levels in a healthy ecosystem, from wild boar disturbing soil by their rooting behaviour, to catastrophic disturbance through occasional large scale fire.! Disturbance brings a dynamic element * to ecosystems, and creates diversity and mosaic-like habitat patches in the landscape.! Disturbance provides the conditions for opportunistic or pioneer species to Flood at the vehicle bridge at Dog * Falls in Glen Affric! thrive, and creates the habitat (eg dead wood) for whole groups of organisms. ! Forestry in the Highlands Conference The importance of predation! Predators exert a ‘top down’ regulatory effect * on ecosystems – they control the numbers of their prey species, which in turn limits the * effects of herbivory.! Predators maintain the health and fitness of their prey, by removing the old, weak, sick etc from the population.! The effects of predators are not just through * the number of animals they kill. Their role as agents of disturbance (eg wolves affecting where deer spend time) are possibly more significant in the ecosystem.! Predation enables the nutrients contained in * their prey species to be retained and recirculated within the ecosystem.! Human actions (eg deer stalking) do not fulfill * all the ecological functions of predators.! Photo © Peter Cairns! Forestry in the Highlands Conference Accomplishments to date:! Forest restoration via natural regeneration" Natural regeneration of birches at Creag Meagaidh NNR! Natural regeneration of Scots pines in Glenfeshie ! Forestry in the Highlands Conference Accomplishments to date:! Forest restoration through tree planting" Left: Planting a pine in Glen Affric in April 1991.! ! Bottom left: The same scene in 2002.! ! Below: May 2011, after 20 years of no grazing.! Forestry in the Highlands Conference Accomplishments to date:! Species recovery" Photo © Laurie Campbell! Photo © Laurie Campbell! Pine marten numbers have increased in The trial reintroduction of European beavers, Scotland have increased in recent decades a keystone species in riparian and aquatic with the expansion of conifer plantations ecosystems, at Knapdale in Argyll, is and native woodland, and a reduction in potentially a major step forward for the persecution! return of Scotland’s missing mammals ! Forestry in the Highlands Conference What might a restored forest look like?! There would be more diversity in the forest - Reindeer lichen, heather, juniper and trees on on better (eg south-facing) sites, oak and an island in a loch on the Hilton Estate. This hazel would take over from birch, through gives an indication of what higher elevation natural succession, with pine as well.! landscapes (505 m.) could look like. ! Forestry in the Highlands Conference Principles of Ecological Restoration! 1.! "Work from areas of strength - the areas where the ecosystem is closest to its natural condition."" " 2.! "Pay particular attention to ‘keystone’ species - those on which many others depend." " 3.! "Utilise processes like the use of pioneer species, natural succession etc to facilitate the restoration process." These are based on the premise that ‘Nature knows best’! Forestry in the Highlands Conference Principles of Ecological Restoration! 4.! "Mimic Nature wherever possible. "" 5."! "Re-create ecological niches where they have been lost." 6."! "Re-establish ecological linkages - reconnect the threads in the web of life." Wood ants tending aphids on an aspen sucker at Dundreggan! Forestry in the Highlands Conference Principles of Ecological Restoration! 7.! "Control and/or remove introduced non-native species."" " 8.! "Remove or mitigate the limiting factors which prevent restoration from taking place naturally." " "Reintroduce species that are 9.! unlikely or impossible to return by themselves." Photo © Liz Balharry! Forestry in the Highlands Conference Principles of Ecological Restoration! 10.! "Re-establish essential ecological processes, eg succession, predation, natural disturbance etc that are absent." " 11.! "Let Nature do most of the work." " 12.! "The ‘green thumb’ principle – human care & love has a tangible, positive effect on all living things to which it is directed." These are based on the premise that ‘Nature knows best’! Trees for Life " Restoring the Caledonian Forest! Participating in restoration has changed lives…! "Did first of many volunteer Weeks * in Glen Affric in 1991"" " "Trained as a group leader in 1995" *" "Organised Sponsored Walks on * Dartmoor & ran