Woodland Management

1

Contents

Introduction ------4

1 Lowland mixed deciduous woodland ------5 1.1 Introduction ------5 1.2 Managing permanent open lowland mixed deciduous woodland ------5 1.3 Managing temporary open lowland mixed deciduous woodland ------7 1.4 Managing regenerating lowland mixed deciduous woodland ------8 1.5 Managing pole stage or thicket lowland mixed deciduous woodland ------10 1.6 Managing mature lowland mixed deciduous woodland ------11 1.7 Managing veteran lowland mixed deciduous woodland ------14

2 Native pine woodland ------17 2.1 Introduction ------17 2.2 Managing permanent open native pine woodland ------17 2.3 Managing temporary open native pine woodland ------19 2.4 Managing regenerating native pine woodland ------20 2.5 Managing native pine thickets with closed canopies ------22 2.6 Managing mature native pine woodland ------22 2.7 Managing veteran native pine woodland ------25

3 Upland mixed ashwoods ------28 3.1 Introduction ------28 3.2 Managing permanent open upland mixed ashwoods ------28 3.3 Managing temporary open upland mixed ashwoods ------30 3.4 Managing regenerating upland mixed ash woodland ------31 3.5 Managing thicket or pole stage upland mixed ash woodland ------32 3.6 Managing mature upland mixed ashwoods ------33 3.7 Managing veteran upland mixed ash woodland ------36

4 Upland birchwoods ------39 4.1 Introduction ------39 4.2 Managing permanent open upland birchwoods------39 4.3 Managing temporary open upland birch woodland ------41 4.4 Managing regenerating upland birch woodland ------42 4.5 Managing mature upland birch woodland ------43 4.6 Managing veteran and ancient upland birch woodland ------46

5 Upland oakwoods ------49 5.1 Introduction ------49 5.2 Managing permanent open upland oakwoods ------49 5.3 Managing temporary open upland oakwoods ------51

2 5.4 Managing regenerating upland oakwoods ------52 5.5 Managing thickets or copses in upland oakwoods ------53 5.6 Managing mature upland oakwoods ------54 5.7 Managing veteran and ancient upland oakwoods ------57

6 Wet woodland ------60 6.1 Introduction ------60 6.2 Managing permanent open wet woodland ------60 6.3 Managing temporary open wet woodland ------61 6.4 Managing regenerating wet woodland ------62 6.5 Managing thickets in wet woodland ------63 6.6 Managing mature wet woodland ------64 6.7 Managing veteran wet woodland ------66

7 Wood pasture and parkland ------69 7.1 Introduction ------69 7.2 Managing permanent open wood pasture and parkland ------69 7.3 Managing regenerating wood pasture and parkland ------71 7.4 Managing mature wood pasture and parkland ------72 7.5 Managing veteran wood pasture and parkland ------75

8 Other non-Biodiversity Action Plan priority woodland habitat types ------79 8.1 Introduction ------79 8.2 Managing coniferous woodland------79 8.3 Managing broadleaved woodland (non-UKBAP habitat types) ------81

3 Introduction

Promote biodiversity in your woodland with this comprehensive guide. You’ll find detailed information on how best to manage each type of woodland to benefit the species that live there.

Funding from the Scottish Rural Development Programme (SRDP) is available for many of the management actions recommended here. For information, see SRDP or other sources of funding.

You’ll find that the woodland habitat types are all aligned with the habitat structures in the Native Woodlands Survey of Scotland, which is a major project carried out by Forestry Commission Scotland.

This woodland advice was prepared by Forest Research for the Woodland Ecosystem Group of the Scottish Biodiversity Forum. The work was funded and managed by Scottish Natural Heritage with assistance from Forestry Commission Scotland, which jointly steered the project.

You can find more detailed information on the species associated with woodland habitats in the following resources:

• Amphibian and Reptile Conservation Trust

• Bat Conservation Trust

• Botanical Society of the British Isles

• Butterfly Conservation

• Forestry Commission

• Froglife

• Habitats and Rare, Priority, Protected Species (HaRPPS)

• Plantlife

• Reptiles & Amphibians of the UK

• RSPB

• Save the Scottish Wildcat

• Mammal Society

• British Lichen Society

• Scottish Fungi

• British Bryological Society

4 1 Lowland mixed deciduous woodland

1.1 Introduction This priority habitat brings together a wide range of lowland woodland types, on well-drained basic to acidic soils on steeply sloping to more or less level ground in the southern and eastern Scottish lowlands. The tree canopy includes varied mixtures of species including oak, downy birch, silver birch, ash, wych elm, sycamore, holly and hazel. In contrast to the situation in upland areas, many of these lowland woods are enclosed by stock-fences or walls.

You’ll find detailed information about managing each woodland type and its niche features in the following sections.

1.2 Managing permanent open lowland mixed deciduous woodland Permanent open woodland occurs where there is a change in vegetation from woodland to open habitat because of site factors. This could be a change in soils (such as areas used as pasture or arable land), geology (rocky outcrops), water availability (ponds, fens and rivers) or where there is a maintained structure such as a road or ride. Woodland rides often support many of the herbs that are historically characteristic of pastures, meadows and mires in the surrounding farmland. Ride margins contain shrubs and small trees, such as dogwood, willow and hazel.

1.2.1 Management

• Mow ride-sides twice yearly to create a short, grassy sward, or annually – in late summer or autumn – to maintain a herb-rich sward.

• Alternatively, graze with cattle at low intensity (c. 12 months at 0.1 animals per ha) but protect different sections from grazing each year.

• Don’t fertilise or reseed open areas which have semi-natural vegetation, or where botanical interest exists. Allow natural vegetation to develop.

• Where soil is fertile, glades used as deer lawns may need to be managed.

5 • Use managed grazing to control invasion of scrub, or cut vegetation using a swipe.

• Cut scrub margins every 2–5 years.

1.2.2 Creation

• When establishing new woodlands, unplantable areas (e.g. because of different land use) will remain as open space. Buffer these with more open space. Leave 50% of the riparian buffer zone unplanted. Leave fertile areas open as deer lawns.

• New rides should be a minimum of 10m wide to prevent shading by developing canopy and east–west rides should be at least 1.5 times wider than tree height on the south side (c. 30m minimum).

• Rides that are orientated in an east–west direction intercept maximum sunlight.

• Further glades, rides and clearings should be connected. Rides should meander through the forest compartments, as straight rides can act as wind tunnels.

• Create glades by felling one or more corners around a ride intersection or fell woodland along rides to create a network of long glades. Include open space when planting next to existing woodland and during restocking of a site.

1.2.3 Managing niche features

Lowland mixed deciduous woodland with permanent open areas supports a range of different niches, including those described below.

Tree bark (dry): well-lit trunks of ash, sycamore or elm, open grown or on the edge of open areas. Trees act as windbreaks and provide more stable conditions.

• Selective thinning or planting, weeding and protection (particularly from grey squirrel) will promote and maintain ash, elm and sycamore trees in the stand next to open ground. Avoid damage or removal of trees in such situations.

• Manage as for bare ground conditions.

Important related species include lesser squirrel-tail moss (Habrodon perpusillus).

Wet ground: ponds, semi-permanent water bodies. Wet areas and temporary puddles can occur behind banks and in depressions, especially on heavy soils.

• Allow water to collect and avoid draining wet areas or cleaning ditches and ponds. Drainage of these patches is undesirable and drainage of the woodland is not recommended.

• Leave material such as harvesting debris or road material if it accumulates nearby.

• Avoid taking heavy machinery over wet soils.

Important related species include great crested newt.

Woodland edge/scrub: border between wooded and open habitats providing shelter or an area covered with stunted trees or shrubs. Both provide cover and shelter.

• Scrub can be coppiced on a 3–20 year rotation, which encourages dense growth of blackthorn and hawthorn, which are beneficial for many species.

• Where rank grass dominates, this can be cut and raked off.

Important related species include great crested newt.

Bare ground: visible topsoil in a mosaic of ground vegetation. Well lit and sheltered. Can be base enriched.

6 • Work on rides and glades in summer to minimise soil damage.

• Control rank vegetation and herbaceous plants by mowing (twice yearly) and/or grazing (c. 12 months at 0.1 animals per ha).

• Deer, rabbits and hares should be maintained at low levels, as they can contribute to creating bare ground but can be damaging in high numbers.

Important related species include narrow-leaved helleborine, adder and slow worm.

Glades: large open areas with a range of vegetation types and heights in a succession from bare ground, short turf, longer vegetation, shrubs and, finally, trees. Soils can be poorly drained.

• Mow the centre of the glade at least once, possibly twice, a year to maintain the short turf using the patch method, whereby small sections (c. 50m lengths) are mown.

• A quarter of tall vegetation should be cut annually and material removed to prevent nutrient build-up and growth of rank weeds.

• Hand cutting is the best method where grasses are not dominant and if cutting can be delayed until late June.

• Treat dense stands of bracken or bramble with herbicides.

• Use low-intensity cattle grazing in autumn. Rotate the areas grazed to increase diversity and ensure that there are areas where plants can flower and set seed.

Important related species include date-coloured waxcap (Hygrocybe spadicea).

1.2.4 Related links

• species associated with permanent open areas of lowland mixed deciduous woodland

• habitat management for amphibians

• habitat management for reptiles

1.3 Managing temporary open lowland mixed deciduous woodland Temporary open areas result from disturbance, and in the context of woodland development may be short lived. For example, they may be replaced by growth of regenerating trees or regrowth of coppice when released from shading by felling overstorey. The open area may have exposed soil or a humus/litter layer or sparse ground vegetation if densely shaded before disturbance. Depending on site richness, plant species already occupying the site and sources of seed available, such open areas can develop species-rich ground vegetation and offer a seed bed for shrubs and tree regeneration (such as bramble and birch). Where ground vegetation is already well developed, this can expand rapidly to fill the site. Examples of activities that result in temporary open habitats are thinning and group felling, cutting along wayleaves and coppicing.

1.3.1 Management

Shorten crop rotations or thin more frequently and heavily.

1.3.2 Creation

• Carry out staged felling of woodland occupying the site and group felling of mature stands once advanced regeneration appears at the end of the rotation (60–150 years, depending on species present).

• Maintain coppiced sites.

1.3.3 Managing niche features

Lowland mixed deciduous woodland with temporary open areas supports different niches, including those described below.

7 Bare ground: visible topsoil in a mosaic of ground vegetation and trees. Low shade at the centre, with increasing shade moving closer to the trees. Can be base enriched.

• Use of machinery during clear-felling creates disturbance and patches of bare ground, but on poorly drained clays heavy machinery can rut and compact the soil. This can result in difficult weed problems with brambles, coarse grasses and rushes. Wherever possible, heavy machinery should be kept to existing tracks and rides or used on a protective bed of lop and top.

• Ground can be bare following coppicing.

• Short rotations (5–15 years) provide the highest benefits.

• Thin out regenerating trees and shrubs to prevent loss and over-shading of bare ground.

Rock (dry): rock in a mosaic of ground vegetation and scrub. Well lit in the centre, getting shadier towards the edges. Warm and sheltered.

• Following thinning/harvesting operations, any lop and top should be spread around rather than heaping or burning (both can lead to nutrient enrichment and beds of nettles).

• If lop and top is burned, the area used for such disposal should be as small as possible.

• Rank vegetation and herbaceous plants overgrowing rocks should be controlled through extensive cattle grazing (c. 12 months at 0.1 animals per ha).

Woodland edge/scrub: border between wooded and open habitats, or an area covered with stunted trees or shrubs. Both provide cover and shelter.

• Scrub can be coppiced on a 3–20 year rotation, which encourages dense growth of blackthorn and hawthorn, which are beneficial for many species.

• Where rank grass dominates, this can be cut and raked off.

Glades: large open areas in woodland, with a range of vegetation types and heights in a succession from bare ground, short turf, longer vegetation, shrubs and, finally, trees.

• Glades can be kept open for longer by cutting and/or grazing.

• A quarter of tall vegetation should be cut annually and any cuttings produced should be removed to prevent nutrient build-up and the growth of rank weeds.

• Where grasses are not dominant, it is best to cut by hand, especially if it can be delayed until late June.

• Exceptionally dense stands of bracken or bramble may be treated with herbicides.

• Use low-intensity cattle grazing (c. 12 months at 0.1 animals per ha); rotate areas grazed to increase diversity and ensure that there are areas where plants can flower and set seed.

1.3.4 Related links

• species associated with temporary open areas of lowland mixed deciduous woodland

1.4 Managing regenerating lowland mixed deciduous woodland This type of woodland has no overstorey. Vegetation is composed of tree seedlings (<1m tall), saplings (trees >1m tall and with girths of up to 7cm diameter at breast height) and shrubs. Shrubs are woody plants usually branching abundantly from the base, >1m tall and usually <5m tall, which may include the following species:

• blackthorn

• bramble

8 • dog rose

• gorse

• guelder rose

• broom

Other species, such as hawthorn, hazel, holly, elder and rowan, may display both shrub and tree forms.

1.4.1 Management

Encourage a shrub boundary for woodland next to other semi-natural habitats.

1.4.2 Creation

• Carry out thinning and staged felling of mature stands at the end of a rotation (70–100 years) once advanced regeneration appears.

• Control browsing in these mature woodlands if the species arising by regeneration within these stands are those wanted in the regeneration/shrub habitat.

• Take care not to cause compaction with machinery, as this may change ground flora composition to one dominated by species preferring wet conditions, such as Juncus.

• Cutting large coupes will encourage natural regeneration and shrubs.

• Naturally occurring regeneration and shrubs can have greater variability in species composition and structure than that which is planted or arising from coppicing.

• In the absence of natural regeneration, plant species that are desirable as components of the woodland habitat.

• Diversity of structure can be created by coppicing species present on the site. Here, control of deer is important, as repeated browsing can kill coppice stools.

• Planting at wide spacing (3–5m) or in clumps is recommended where timber production is not the management aim.

• Enrichment planting 2–3 years after felling will ensure a stock of the desired species within a matrix of natural growth.

1.4.3 Managing niche features

Regenerating lowland mixed deciduous woodland supports several different niches, including those described below.

Woodland edge/scrub: border between wooded and open habitats, or an area covered with stunted trees or shrubs. Both provide cover and shelter.

• Scrub can be coppiced on a 3–20 year rotation, which encourages dense growth of blackthorn, hawthorn and dogwood, and is beneficial for many species.

• More frequent cutting may be necessary where bramble dominates.

• Where rank grassland dominates, this can be cut and raked off.

Important related species include hedge accentor (dunnock), bullfinch and otter.

Glades: large open areas in woodland, with a range of vegetation types and heights in a succession from bare ground, short turf, longer vegetation, shrubs and, finally, trees.

• Use low-intensity cattle grazing in autumn (equivalent to a rate of c. 0.1 animals per ha for 12 months).

9 • Rotate the areas grazed, protecting some areas from grazing each year, to increase diversity and ensure that plants can flower and set seed on part of the site.

• Exceptionally dense stands of bracken or bramble may be treated with herbicides.

• Mow the centre of the glade at least once, or possibly twice, a year to maintain the short turf using the patch method, whereby small sections (c. 50m lengths) are mown.

• A quarter of tall vegetation should be cut annually and any cuttings produced should be removed to prevent nutrient build-up and the growth of rank weeds.

• Where grasses are not dominant, this is best done by hand cutting, especially if it can be delayed until late June.

Important related species include song thrush, tree pipit and cuckoo.

1.4.4 Related links

• species associated with regenerating lowland mixed deciduous woodland

1.5 Managing pole stage or thicket lowland mixed deciduous woodland In a thicket, trees and shrubs fill the area, and some trees in the canopy and shrubs in the understorey die as a result of competition. Ground flora is shaded out. There is no colonisation by other plants. Trees and shrubs are too young to bear seed/fruit. Trees usually have a diameter at breast height of >7cm and are above 5m tall.

1.5.1 Management

It is difficult to perpetuate stands at pole stage unless woodland is dominated by one species and is on a very uniform site. Management of this structural type is usually aimed at influencing the composition and structure of ‘mature’ woodland.

1.5.2 Creation

Composition and stand density are influenced by site management in previous rotations, e.g. control of browsing of the regeneration in the previous stand, and during restocking from the choice of species planted. High stocking rates (c. >10,000 trees per ha) during the planting phase will allow this structure to develop more quickly and are likely to increase deadwood provision.

1.5.3 Managing niche features

Lowland mixed deciduous woodland with thickets supports several different niches, including those described below.

Deadwood: rotting wood in sheltered closed canopy woodland.

• Promote high stocking rates during previous stages of stand development through grazing management and planting.

• Leave dead limbs in situ after harvesting, preferably close to existing trees or areas of semi-natural vegetation. Aim for >30m3 deadwood per ha.

Important related species include slender thread-moss (Orthodontium gracile).

Rock (humid): calcareous rock shaded by a dense tree canopy.

• Rank vegetation and herbaceous plants should be controlled by grazing (equivalent to rate of c. 0.1 animals per ha for 12 months) and perhaps through mowing (twice yearly) where practicable.

• Weed problems can result from local enrichment where lop and top is left lying or is burned.

• Following thinning or harvesting operations, any lop and top should be spread around.

10 • On poorly drained clays, weed problems with brambles, coarse grasses and rushes can be caused by harvesting machinery compacting soil. Heavy machinery should be kept to existing tracks and rides or used on a protective bed of lop and top.

Important related species include incurved feather-moss (Homomallium incurvatum) and slender thread-moss.

Tree bark (dry): smooth bark of young ash, hazel and aspen in sheltered closed canopy woodland.

• Encourage provision of new ash, aspen and hazel trees during previous stages of stand development through grazing management and planting.

1.5.4 Related links

• species associated with lowland mixed deciduous woodland thickets

1.6 Managing mature lowland mixed deciduous woodland Mature woodland is characterised by:

• trees producing seed/fruit

• crown/canopy spreading and at maximum development

• canopy die-back (up to 10%) from competition for light and/or wind/snow damage

Ground flora is developed and there is a woodland floor with regenerating trees and shrubs. All trees >5m tall. Diameters of trunks at breast height are as below:

• birch and aspen: 20–50cm

• rowan and cherry: 20–75cm

• alder: 20–80cm

• oak: 30–100cm

• ash: 20–100cm

• elm and beech: 30–150cm

• sycamore: 20–150cm

1.6.1 Management

In the long term, maintain an all-sized (old growth) structure using group felling combined with retention of a few (<5 per ha) old trees, to develop into veterans.

• Regenerate ash, sycamore and wych elm under the canopy or in small gaps.

• Regenerate oak, birch, hazel and hawthorn using larger group fellings – gaps of 0.5–2ha created. However, note that dense growth of bramble and/or bracken may develop in larger openings on oak and birch sites.

• Retain old trees individually or in groups in wind-firm locations.

• An all-sized structure can be achieved in derelict coppice by singling overgrown coppice plants (providing stool is still vigorous).

1.6.2 Creation

The structure and species composition of the stand present will be influenced by:

11 • Previous rotation management favouring regeneration of certain species; enrichment planting during regeneration stage; respacing in early pole stage; respacing by selecting two trees >2m apart every 10m, and clearing around these to create a gap the diameter of the surrounding trees.

• Selective thinning in late pole stage further influences species composition of the canopy. Identify as stand dominants 150 stems of oak, 200 stems of ash and sycamore, and 300 stems of birch per ha. Fell all surrounding trees with crowns in competition. Lightly thin matrix. Repeat every 5–10 years and apply to areas >2ha.

• For biodiversity, trees to remain should have irregular form, including snapped limbs. Retain suppressed stems, as these may be older than surrounding trees and have developed a more diverse epiphytic community.

1.6.3 Managing niche features

Mature lowland mixed deciduous woodland supports a range of different niches, including those described below.

Wet ground: ponds and semi-permanent water bodies. Wet areas and temporary puddles can occur behind banks and in depressions, especially on heavy soils.

• Allow water to collect.

• Leave material such as harvesting debris or road material if it accumulates nearby.

• Avoid taking heavy machinery over wet soils.

• Avoid draining wet areas or cleaning ditches and ponds. Drainage of the woodland is not recommended.

Important related species include noctule and great crested newt.

Bare ground: visible topsoil in a mosaic of ground vegetation. Well lit but sheltered, as surrounded by trees. Can be base enriched.

• Using machinery during harvesting creates disturbance and patches of bare ground.

• Thin out regenerating trees and shrubs to prevent loss and over-shading. Take care on steep slopes, as there will be a risk of erosion and damage to the thin layer of litter, including fungi.

Important related species include adder and slow worm.

Tree bark (dry): bark of a variety of species (ash, elm, sycamore and aspen), flaking, rough or smooth, shaded or well lit, but generally dry and in sheltered locations.

• Manage for all-sized structure and encourage diverse composition of tree species during earlier phases of woodland management.

• Do not halo thin around trees, but leave in groups.

Important related species include spotted flycatcher, lesser squirrel-tail moss and dwarf bristle-moss (Orthotrichum pumilum), brown long-eared bat, soprano pipistrelle, noctule and red squirrel.

Deadwood: large fallen and standing deadwood (trees and snags, diameters >30cm) providing hollows and high stumps.

• The deadwood target is >30m3 per ha. Leave dead limbs in situ and artificially increase deadwood through ring barking or removing crowns and creating high stumps. Consider accelerating this by wounding (routing) younger trees or inoculating trees with decay-forming fungi (formation of tree cavities in oak naturally takes more than 200 years).

• Set aside some areas of minimal intervention to allow natural build-up of deadwood.

Important related species include willow tit and hawfinch.

12 Woodland edge/scrub: border between wooded and open habitats providing shelter or an area covered with stunted trees or shrubs.

• Scrub can be coppiced on a 3–20 year rotation, which encourages dense growth of blackthorn and hawthorn.

• Where rank grassland dominates, this can be cut and raked off.

Important related species include hawfinch, willow tit, wood warbler, great crested newt and otter.

Complex understorey with glades: shrubs and regenerating trees forming a layer below the woodland canopy of variable height and density and containing small openings with sheltered conditions.

• Coppice scrub every 3–20 years.

• Control bramble and bracken competition by cutting, hand-pulling, rolling or ploughing. If necessary, herbicides may be used.

Important related species include brown long-eared bat, soprano pipistrelle, red squirrel and barred tooth-striped (moth, Trichopteryx polycommata).

Tree bark (humid): wound seepage tracks and rain tracks of bark of old trees (elm, ash, sycamore, holly and beech).

• Manage for all-sized structure and encourage diverse composition of tree species during earlier phases of woodland management.

• Select for trees with wounded bark during thinning operations.

Glades: large open areas in the woodland, with a range of vegetation types and heights in a succession from bare ground, short turf, longer vegetation, shrubs and, finally, trees. Soils can be poorly drained.

• On poorly drained clays, heavy machinery can rut and compact the soil and generate weed problems (brambles, coarse grasses and rushes).

• Wherever possible, heavy machinery should be kept to existing tracks and rides or used on a protective bed of lop and top.

Important related species include spotted flycatcher.

Rock (dry): dry shade below boulders or shaded calcareous rock faces.

• Avoid moving rocks.

• Rank vegetation and herbaceous plants should be controlled by grazing (equivalent to a rate of c. 0.1 animals per ha for 12 months) and perhaps through mowing (twice yearly) where practicable.

• Avoid enrichment of the site by leaving lop and top heaped around rocks after harvesting operations (spread it around).

1.6.4 Related links

• species associated with mature lowland mixed deciduous woodland

• managing woodlands and their mammals

• red squirrel – SNH

• red squirrel – Forestry Commission

• action for red squirrels

• habitats and rare, priority, protected species – otter

13 • great crested newt conservation handbook

• barred tooth-striped (moth)

1.7 Managing veteran lowland mixed deciduous woodland Veteran woodland is characterised by the presence of individual trees that have a large girth. Minimum diameters at breast height of greater than:

• birches, hawthorn, rowan, holly, cherry, goat willow, grey willow, aspen and hazel: 50cm

• oaks, ash, yew, field maple and hornbeam: 100cm

• elms, sycamore, beech, sweet chestnut, lime, horse chestnut, poplars and other willows: 150cm

Woodland will show at least three signs of old growth and decay from this list:

• major trunk cavities/progressive hollowing

• naturally forming water pools in major forks

• rot/decay holes >5cm diameter

• rot/decay sites, physical damage to trunks

• bark loss/loose bark

• large quantities of deadwood in the canopy

• sap runs

• crevices in the bark, under branches or in the root plate

• fungal fruiting bodies (e.g. from heart-rotting species)

• epiphytic plants (ferns, mosses, liverworts and lichens)

• high aesthetic interest (e.g. pollard or old coppice stool)

1.7.1 Management

Retain all veteran and ancient trees. Treat each tree individually.

• Undertake minimum remedial work, such as lowering crown height to reduce risk of windblow.

• If managed by pollarding in the past, reinstate with care using a process called ‘retrenchment’.

• Maintain open canopy around existing trees and don’t allow young trees to over-shadow them. Avoid sudden changes. So, gradually open up surrounding tree cover and reduce height by pollarding of the surrounding canopy, or ring bark surrounding trees to decrease the shade slowly over a period of time.

1.7.2 Creation

Identify younger trees as replacements. Encourage open growth of these by thinning around them.

• In mature stands where understorey regeneration has begun and removal of the overstorey is planned, retain some mature trees that can develop into veterans.

• Marginal trees, and trees growing in inaccessible places and along steep-sided stream sides, very wet areas and sites with very shallow and drought-prone soils, should be retained indefinitely and left completely unmanaged.

14 • Large old coppice stools can be retained by cutting above the level of the last cut. Ideally, new pollards should be started on internal and external boundaries.

1.7.3 Managing niche features

Veteran lowland mixed deciduous woodland supports a range of different niches, including those described below.

Woodland edge/scrub: border between wooded and open habitats or an area covered with stunted trees or shrubs. Both provide cover and shelter.

• Scrub can be coppiced on a 3–20 year rotation, which encourages dense growth of blackthorn and hawthorn.

• Where rank grassland dominates, this can be cut and raked off.

• If next to a road or open area, apply ride-side management using low-impact intervention, such as hand weeding, to prevent competitive species from dominating.

• Leave any established shrubs. Consider planting a scattering of shrubs if regeneration does not occur.

• Scalloping replaces straight woodland edges with more natural, diffuse ones. Scallops should be up to 20m long and 20–50m deep, to provide bays that offer more shelter from the wind.

• Stop any ride widening c. 20m from a woodland edge.

Important related species include willow tit and wood warbler.

Tree bark (dry): rough bark of a variety of species (ash, elm, sycamore and beech), shaded or well lit, but generally dry.

• Avoid damage or removal of limbs with bark features such as crevices, wounds and rain tracks.

• Manage the stand with selective thinning or planting to ensure a supply of native trees, including ash, elm, oak and sycamore.

• Retain trees that are suppressed, slow growing or showing signs of stress (such as cracking and splitting), as these are more likely to develop bark features and succumb to wood decay fungi, which are important in making bark more suitable for bark-living species (raising pH).

• Inoculation of trees with wood decay fungi could be attempted.

Important related species include spotted flycatcher, Bacidia subincompta (lichen) and lesser squirrel-tail moss.

Tree bark (humid): wound seepage tracks and rain tracks of bark of old trees (elm, ash, sycamore, holly and beech).

• Avoid damage or removal of limbs with bark features such as crevices, wounds and rain tracks.

• Manage the stand (selective thinning or planting) to ensure a supply of native trees, including ash, elm, oak and sycamore.

• Retain trees that are suppressed, slow growing or showing signs of stress (e.g. cracking and splitting), as these are more likely to develop bark features and succumb to wood decay fungi, which are important in making bark more suitable for bark-living species (raising pH).

• Inoculation of trees with wood decay fungi could be attempted.

Important related species include Bacidia incompta (lichen).

Rock (dry): dry shade below boulders.

• Avoid moving rocks.

• Rank vegetation and herbaceous plants should be controlled by grazing (equivalent to a rate of c. 0.1 animals per ha for 12 months) and perhaps through mowing (twice yearly) where practicable.

15 Deadwood: large fallen and standing deadwood (trees and snags, diameters >30cm) providing hollows and high stumps.

• Leave all deadwood standing and fallen in situ. Prevent an increase in shading of existing deadwood.

• Pollard hollow trees to increase longevity. Aim for a continuous supply of deadwood of >30m3 per ha.

Important related species include willow tit.

1.7.4 Related links

• species associated with veteran lowland mixed deciduous woodland

16 2 Native pine woodland

2.1 Introduction This is woodland with a canopy dominated by native Scots pine (Pinus sylvestris). Other trees and shrubs can occur, especially silver birch, downy birch, rowan, aspen, grey willow, eared willow and juniper. The ground vegetation is typically heath-like. This habitat occupies well-drained to quite wet acid soils and occurs in association with other habitats, including birch woodland, wet woodland, heaths (both wet and dry), bogs, bracken, grasslands, cliffs and screes.

It is restricted to that part of the Scottish Highlands in which Scots pine occurs as a native species. Good management for conservation in this habitat generally aims towards:

• maintaining a good diversity of species, sizes and age classes of trees and shrubs

• encouraging diversity in the structure and species composition of the ground vegetation

• maintaining rich bryophyte and lichen assemblages on rocks and trees, especially in the west

• maintaining good quantities of standing and fallen deadwood

• controlling the extent and spread of non-native trees and shrubs, especially rhododendron (Rhododendron ponticum)

2.2 Managing permanent open native pine woodland Permanent open areas occur where the change in vegetation from woodland to open habitat is due to underlying site factors, such as change in soils (e.g. apparent as bracken areas), geology (e.g. hard knolls and scree slopes), water availability (e.g. mire, sedge-rich flushes and bogs) or where there is a maintained structure, such as a road or ride or downfalls for red deer in the uplands so they can reach wintering grounds. Areas of wet and dry heath are maintained by management.

17 2.2.1 Management

• Use light grazing regimes (c. 3–4 months at 0.1 animals per ha) to maintain openness and diversity in composition and structure of vegetation. A rotational grazing system where part of the area is left ungrazed each year will promote diversity and ensure that there are areas where plants can flower and set seed. In areas with high deer numbers, control measures should be implemented to prevent overgrazing.

• Don’t fertilise open areas because of the effect on the composition of semi-natural vegetation.

• Don’t drain damp areas or mires.

2.2.2 Creation

• When establishing new woodlands, areas which are unplantable, e.g. due to exposure, rock outcrops, water or different land use, will be left as open space. Don’t encourage natural regeneration too close to such features.

• Rides, where possible, should be orientated in an east–west direction to increase the total hours of sunlight. Further glades, rides and clearings should be connected.

• Create open areas by felling or heavy thinning of self-seeded trees, followed by grazing.

• Develop glades by felling one or more corners around a ride intersection to create and maintain glades. Fell woodland along rides to create a network of long glades.

• Don’t clear significant areas of woodland, particularly on ancient woodland sites.

2.2.3 Managing niche features

Native pine woodland with permanent open areas supports a range of different niches, including those described below.

Bare ground: visible sandy topsoil in a mosaic of ground vegetation. Sheltered with a mixture of well-lit and shaded conditions.

• Use low-intensity cattle grazing (c. 3–4 months at 0.1 animals per ha) in autumn to help maintain bare ground in areas disturbed during thinning operations.

• Clear regeneration from some areas to prevent over-shading.

Important related species include adder.

Wet ground: ponds, semi-permanent water bodies and areas of poor drainage, e.g. water in wheel ruts and ditches.

• Allow water to collect and avoid draining wet areas or cleaning ditches and ponds.

• Leave material such as harvesting debris or road material if it accumulates nearby.

• Avoid taking heavy machinery over wet soils.

Important related species include great crested newt.

Deadwood: pine tree stumps and other deadwood in a mosaic with herb-rich ground flora.

• Retain in situ all standing and fallen deadwood.

• Create stumps by felling (diameters >30cm) and creating high stumps.

• Retain deadwood created from windblow and other natural processes.

Woodland edge/scrub: border between wooded and open habitats providing cover and shelter next to water.

• Respace natural regeneration or thin the edge or scrub zone to create a mosaic of structural diversity and different aged shrubs.

18 • Leave lop and top in place to create cover.

Important related species include great crested newt.

Glades: open areas, with short vegetation; can contain a scatter of small trees and shrubs.

• Use low-intensity cattle grazing (c. 3–4 months at 0.1 animals per ha), preferably in autumn, to maintain open conditions and diverse ground vegetation (species and height).

• Clear dense regeneration from some areas to prevent over-shading, but allow juniper and a few birch trees to establish.

Important related species include nightjar, narrow-headed ant (Formica exsecta) and juniper.

Tree bark (dry): smooth, well-lit bark of aspen at woodland edge.

• Use selective thinning or planting, weeding and protection to maintain aspen in the stand. Avoid damage or removal of limbs with bark features, such as crevices, wounds and rain tracks.

2.2.4 Related links

• species associated with permanent open areas of native pine woodland

• habitat management for amphibians

• habitat management for reptiles

• BSBI species accounts – juniper

• managing uplands for juniper

2.3 Managing temporary open native pine woodland These are areas where soils are suitable for native woodland communities and there is potential for woodland habitat to develop, but there are no trees and no regeneration. Areas can contain deadwood, indicating past woodland status. Sites subject to removal of woodland canopy in the past and intensive and continued grazing or browsing could be classed as temporary open areas, as they have the potential to support woodland again.

Other temporary open habitats result from removal of woodland canopy as part of the woodland development cycle. Such open habitats may be short lived and, for example, replaced by growth of regenerating trees. Open areas are likely to have vegetation cover unless the ground has been disturbed, for example during harvesting.

2.3.1 Management

• Hand weed around planted trees (preferably delayed until July).

• Herbicides should only be used if grass is dominant and then in spot applications of 1m diameter around young trees.

2.3.2 Creation

• Fell areas of mature pinewood at the end of the rotation (c. 60 years old).

• Respace thick clumps of pine regeneration.

• Carry out heavy and early thinning of pole stage stands.

2.3.3 Managing niche features

Native pine woodland with temporary open areas supports several different niches, including those described below.

19 Bare ground: visible sandy topsoil often in areas kept bare of litter cover, e.g. along tracks or on banks but with minimal soil disturbance. Occurring in a mosaic of short ground vegetation next to trees. Sheltered and a mixture of well-lit and shaded conditions.

• Use low-intensity cattle grazing (c. 3–4 months at 0.1 animals per ha) in autumn or mowing twice yearly to help maintain bare ground in areas, such as along paths and banks or disturbed during past thinning operations.

• Clear regeneration from some areas to prevent over-shading.

Important related species include orange tooth fungus (Hydnellum aurantiacum), blue tooth fungus (Hydnellum caeruleum), mealy tooth fungus (Hydnellum ferrugineum), devil’s tooth fungus (Hydnellum peckii), ridged tooth fungus (Hydnellum scrobiculatum), woolly tooth fungus (Phellodon tomentosus), greenfoot tooth fungus (Sarcodon glaucopus) and scaly tooth fungus (Sarcodon squamosus).

Deadwood: large deadwood (standing, fallen or cut tree stumps), from harvesting debris or created through natural tree ageing and the colonisation of fungi, lichens and saproxylic invertebrates.

• Retain all standing and fallen deadwood in situ.

• Create stumps by felling (diameters >30cm) and creating high stumps.

• Retain deadwood created from windblow and other processes.

2.3.4 Related links

• species associated with temporary open areas within native pine woodland

• Scotland’s rare tooth fungi management guide

2.4 Managing regenerating native pine woodland This is woodland without an overstorey but with dense seedling and/or sapling recruitment. Vegetation is composed of tree seedlings (<1m tall), saplings (<1m tall and with girths of up to 7cm diameter at breast height) and shrubs. Pine can regenerate to form dense thickets. Other trees that are natural components of pinewoods include birch, alder, sallow, rowan and holly, plus occasional oak, hazel and aspen, and there are a number of shrub species too. Shrubs are woody plants usually branching abundantly from the base, >1m tall and usually <5m tall, of the following species:

• juniper

• eared willow

• other species such as rowan may display both shrub and tree forms

2.4.1 Management

Prevent browsing and protect woodland from major fires.

2.4.2 Creation

• Control deer browsing and sheep grazing to encourage natural regeneration.

• Increase species diversity through herbivore control to allow the more palatable species, such as birch, alder, sallow, rowan, holly, oak, hazel and aspen, to establish.

• Maintain low levels of grazing for long periods to encourage a diversity of species to regenerate. It may be necessary to plant locally important species where seed sources are limited and to establish slow colonisers, such as juniper or aspen.

• In well-stocked woods, fell mature stands (>60 years old) once regeneration begins to appear to improve establishment and growth of shrubs/regeneration following a shelterwood or clear-felling system. Coupes should

20 not exceed 3ha, or cover more than a quarter of the woodland. Shelterwood coupes should retain a basal area threshold of c. 18m2 per ha. Clear-felled coupes should not be wider than 60m.

• To encourage natural regeneration, ground preparation should be locally intensive, spatially irregular but localised to below canopy gaps. In drier eastern pinewoods, patch scarifying is recommended; in wetter, western pinewoods low mounding is recommended. Even if advanced regeneration is not present, some areas of woodland should be thinned heavily to develop a vigorous shrub and field layer.

2.4.3 Managing niche features

Regenerating native pine woodland supports a range of different niches, including those described below.

Bare ground: visible sandy topsoil often occurs in areas kept bare of litter cover, e.g. along tracks or on banks but with minimal soil disturbance; occurs in a mosaic of short ground vegetation next to trees; sheltered and with a mixture of well- lit and shaded conditions.

• Use low-intensity cattle grazing (c. 3–4 months at 0.1 animals per ha) in autumn to help maintain bare ground disturbed during past thinning operations.

• Mowing can be used twice yearly to maintain bare ground along paths and banks.

• Clear regeneration from some areas to prevent over-shading.

Important related species include orange tooth fungus and mealy tooth fungus.

Complex understorey with glades: shrubs, small trees and regenerating trees forming a layer below the woodland canopy of variable height and density and containing small openings where conditions are shaded and humid.

• Clear regeneration from some areas to create glades. Allow some continued disturbance (low-intensity cattle grazing) to cause patchy regeneration.

Important related species include song thrush.

Woodland edge/scrub: border between wooded and open habitats containing regenerating aspen and providing shelter.

• Encourage structural diversity and a mosaic of different aged shrubs in the edge or scrub zone through grazing and browsing. The respacing of natural regeneration will help.

• Allow aspen suckers to invade adjacent open areas.

• Leave any cut material in place to create cover.

Important related species include otter and dark bordered beauty (moth).

Glades: large open areas in the woodland containing grassland, dwarf shrubs and herbs.

• Use low-intensity cattle grazing (c. 3–4 months at 0.1 animals per ha), preferably in autumn, to maintain open conditions and diverse ground vegetation (species and height).

• Clear dense regeneration from some areas to prevent over-shading.

• Fell one or more corners around a ride intersection to create and maintain glades, or fell woodland along rides to create a network of long glades.

Important related species include nightjar.

2.4.4 Related links

• species associated with regenerating native pine woodland

• Scotland’s rare tooth fungi management guide

21 2.5 Managing native pine thickets with closed canopies Pine naturally develops in even-sized stands. Tree canopies fill the available space and compete directly with each other, ground flora is shaded out and no plants colonise. Some canopy trees and understorey shrubs die as a result of competition; neighbouring trees fill gaps through canopy expansion. Tree density is high (>1,000ha per ha, basal area >25m2 ha per ha). Trees have a diameter at breast height >7cm and <35cm and are usually >5m in height. Trees and shrubs have not begun bearing seed/fruit (immature). There is an accumulation of small-diameter standing deadwood.

2.5.1 Management

Non-intervention will maintain woodland at this stage for longer.

2.5.2 Creation

Intervene to encourage natural regeneration of pine and other tree species:

• Control browsing and prepare the ground to ensure that thickets of regeneration occur and dense stands are established in pole stage.

• Fell mature, overstorey trees from previous crop to encourage growth of regenerating trees and development of woodland to pole stage.

2.5.3 Managing niche features

Native pine thickets with closed canopies support several different niches, including those described below.

Bare ground: visible sandy topsoil often in areas kept bare of litter, e.g. along tracks or on banks with minimal soil disturbance, in a mosaic of short ground vegetation next to trees. Sheltered and a mixture of well-lit and shaded conditions.

• Use low-intensity cattle grazing (c. 3–4 months at 0.1 animals per ha) in autumn to help maintain bare ground from past thinning operations.

• Mow twice yearly to maintain bare ground along paths and banks.

• Clear regeneration from some areas to prevent over-shading.

Important related species include devil’s tooth fungus, ridged tooth fungus, woolly tooth fungus, greenfoot tooth fungus and bitter tooth fungus.

Rock (humid): rocks in humid, shaded conditions, e.g. ravines, flushes and with dense tree canopy cover.

• Avoid thinning the tree canopy where it shades ravines or flushes.

• Maintain site drainage (don’t add new drainage ditches or block existing ones).

• Use low-intensity cattle grazing (c. 3–4 months at 0.1 animals per ha) in autumn to control rank growth of grasses and herbs and dense regeneration, e.g. rhododendron or beech (possible in more westerly woods).

2.5.4 Related links

• species associated with native pine woodland thickets

• Scotland’s rare tooth fungi management guide

2.6 Managing mature native pine woodland This is woodland where:

• Trees produce seed, and growth of canopy trees has begun to significantly slow down.

• The mortality of individuals no longer stimulates canopy expansion of neighbouring trees.

22 • The crown/canopy is usually spreading and at its maximum development.

• There may be canopy die-back of up to 10% as a result of competition for light and/or wind/snow damage.

Ground flora is developed and shrubs and regenerating trees appear on the woodland floor. Trees c. 150 years old, basal area 25–40m2 per ha. All (non-tree-line trees) are greater than 5m tall and diameters of trunks at breast height are in the range listed below:

• birches: 20–50cm

• aspen: 20–50cm

• rowan: 20–75cm

• alder: 20–80cm

• Scots pine: 35–80cm

2.6.1 Management

• To maintain mature all-sized structure (old growth), reduce stocking density/basal area to 10–20m2 per ha and crown thin to develop seed-bearing native trees (100–150 per ha).

• Carry out suitable site disturbance and underplant with native broadleaved tree species.

2.6.2 Creation

Although pine is capable of natural self-thinning, carry out respacing and repeated crown thinning during pole stage to ensure that all the species in mixed stands are maintained for as long as possible somewhere in the stand and to increase structural diversity. The species mixture is dependent on management during earlier stages of woodland development. For this, a maximum of 20% of stand basal area should be removed in each intervention. Repeat interventions every 4–15 years.

2.6.3 Managing niche features

Mature native pine woodland supports a range of different niches, including those described below.

Bare ground: visible sandy topsoil often with areas kept bare of litter cover, e.g. along tracks or on banks but with minimal soil disturbance, in a mosaic of short ground vegetation next to trees. Sheltered with a mixture of well-lit and shaded conditions.

• Use low-intensity cattle grazing (c. 3–4 months at 0.1 animals per ha) in autumn to help maintain bare ground from past thinning operations.

• Mowing can be used twice yearly to maintain bare ground along paths and banks.

• Clear regeneration from some areas to prevent over-shading.

Important related species include adder and drab tooth fungus (Bankera fuligineoalba), blue tooth fungus, devil’s tooth fungus, ridged tooth fungus, woolly tooth fungus, greenfoot tooth fungus, bitter tooth fungus and black tooth fungus (Phellodon niger).

Deadwood: large deadwood (standing, fallen or cut tree stumps) generally created through natural tree ageing and the colonisation of fungi, lichens and saproxylic invertebrates.

• Retain all standing and fallen deadwood in situ (target >30m3 per ha).

• Create deadwood by retaining unmanaged clumps together and scattered trees in felling coupes, or mother trees in shelterwood fellings, windblown trees, trees in inaccessible places (steep-sided stream sides, rock outcrops and sites on steep slopes with very shallow and drought-prone soils).

23 • Enhance tree mortality by killing standing trees of different sizes by injuring, ring barking or removing crowns and creating high stumps.

Important related species include pine hoverfly (Blera fallax) and green shield-moss (Buxbaumia viridis).

Woodland edge/scrub: border between wooded and open habitats providing shelter and cover.

• Encourage structural diversity and a mosaic of different aged shrubs in the edge or scrub zone through grazing and browsing, although this can be helped through respacing of natural regeneration.

• Allow aspen suckers to invade adjacent open areas.

• Leave any cut material in place to create cover.

Important related species include otter and great crested newt.

Tree bark (dry): clefts in branches, flaking bark and bark crevices (range of tree species); smooth well-lit bark of aspen trees.

• Avoid damage to or removal of limbs with clefts and flaking bark.

• Thin selectively to retain aspen trees in well-lit conditions and to encourage growth of replacement aspens.

Important related species include spotted flycatcher, soprano pipistrelle, brown long-eared bat, red squirrel, pine marten, scaly tooth fungus (Sarcodon squamosus), grey tooth fungus (Phellodon melaleucus), blunt-leaved bristle-moss (Orthotrichum obtusifolium), dwarf bristle-moss, aspen bristle-moss (Orthotrichum gymnostomum) and Schismatomma graphidioides (lichen).

Complex understorey with glades: shrubs, small trees and regenerating trees forming a layer below the woodland canopy of variable height and density and containing openings where conditions are shaded, humid and sheltered, with sedges and grasses on wetter ground and heather and blueberry cover on drier areas.

• Clear regeneration from some areas to create glades.

• Arrange some continued disturbance (low-intensity cattle grazing) to cause patchy regeneration.

Important related species include black grouse, capercaillie, spotted flycatcher, soprano pipistrelle, brown long-eared bat, red squirrel, pine marten, Scottish wildcat and juniper.

Wet ground: ponds, semi-permanent water bodies and areas of poor drainage, e.g. water in wheel ruts and ditches.

• Allow water to collect and avoid draining wet areas or cleaning ditches and ponds.

• Leave material such as harvesting debris or road material if it accumulates nearby.

Important related species include great crested newt.

2.6.4 Related links

• species associated with mature native pine woodland

• habitat management for amphibians

• habitat management for reptiles

• Scotland’s rare tooth fungi management guide

• managing woodlands and their mammals

• action for red squirrels

• habitats and rare, priority, protected species – scaly tooth fungus

24 • BSBI species accounts – juniper

• managing uplands for juniper

2.7 Managing veteran native pine woodland Veteran woodland is characterised by the presence of individual trees showing at least three signs of the old growth and decay features listed below:

• major trunk cavities/progressive hollowing

• naturally forming water pools in major forks

• rot/decay holes >5cm diameter

• rot/decay sites, physical damage to trunks

• bark loss/loose bark

• large quantities of deadwood in the canopy

• sap runs

• crevices in the bark, under branches or in the root plate

• fungal fruiting bodies (e.g. from heart-rotting species)

• epiphytic plants (ferns, mosses, liverworts and lichens)

• high aesthetic interest (e.g. pollard or old coppice stool)

Such veteran trees may also have a large girth. Minimum diameter at breast height of:

• birches: 50cm

• rowan: 75cm

• Scots pine: 80cm

2.7.1 Management

Retain all veteran and ancient trees. Treat each tree individually and do as little remedial work as possible.

• Prolong the life of older trees by lowering crown height to reduce the risk of windblow.

• Maintain open canopy around existing trees and don’t allow young trees to over-shade them; however, avoid sudden changes around veteran and ancient trees by gradually opening up surrounding tree cover. For example, pollard surrounding trees to reduce the height of the surrounding canopy or ring bark (or other equivalent methods) surrounding trees to decrease the shade slowly over a period of time.

2.7.2 Creation

• Identify younger/smaller trees as replacements.

• During harvesting activities of mature forest (>60 years), retain clumps and scattered trees in felling coupes, or trees in shelterwood fellings past commercial maturity.

• Some areas should be crown thinned to produce large flat-crowned trees, selecting individuals already showing signs of ageing (or artificially age by wounding).

• Identify areas of the pinewood where no further fellings will take place.

25 • Where trees are in awkward or remote corners, on steep-sided stream sides, rock outcrops or steep slopes with very shallow and drought-prone soils, they should be left completely unmanaged.

2.7.3 Managing niche features

Veteran native pine woodland supports a range of different niches, including those described below.

Bare ground: visible sandy topsoil often with areas kept bare of litter cover, e.g. along tracks or on banks but with minimal soil disturbance, in a mosaic of short ground vegetation next to trees. Sheltered and a mixture of well-lit and shaded conditions.

• Use low-intensity cattle grazing (c. 3–4 months at 0.1 animals per ha) in autumn to help maintain bare ground from past thinning operations.

• Mow twice yearly to maintain bare ground along paths and banks.

• Clear regeneration from some areas to prevent over-shading.

Important related species include drab tooth fungus and ridged tooth fungus.

Deadwood: large deadwood (standing, fallen or cut tree stumps) generally created through natural tree ageing and the colonisation of fungi, lichens and saproxylic invertebrates.

• Leave all standing and fallen deadwood in situ. Aim for a continuous supply of deadwood on the site (target >30m3 per ha and more than 50 standing dead trees, some over 40cm in diameter).

• Consider inducing rot in some trees.

Important related species include pine hoverfly and aspen hoverfly (Hammerschmidtia ferruginea).

Woodland edge/scrub: border between wooded and open habitats providing shelter and cover.

• Encourage structural diversity and a mosaic of shrubs in the edge or scrub zone through grazing and browsing. This can be helped through respacing of natural regeneration.

• Allow aspen suckers to invade adjacent open areas.

• Leave cut material in place to create cover.

Tree bark (dry): forks in branches, well-lit bark, flaking bark and large cavities within standing trees.

• Avoid damage to hollow trunks or removal of limbs with cavities and bark features, such as crevices.

• Protect trees retained as replacements and encourage frequent natural regeneration events to reduce the age gap between cohorts, as the time between the regeneration of trees and the formation of tree cavities is long (c. 200 years).

• Consider accelerating the development of structures by wounding (routing) younger trees or inoculating young trees with decay-forming fungi, provided this does not kill trees.

Important related species include spotted flycatcher, soprano pipistrelle, brown long-eared bat, red squirrel, pine marten, Schismatomma graphidioides (lichen), drab tooth fungus, blue tooth fungus, devil’s tooth fungus, ridged tooth fungus, woolly tooth fungus, greenfoot tooth fungus, bitter tooth fungus and black tooth fungus.

Complex understorey with glades: shrubs, small trees and regenerating trees forming a layer below the woodland canopy of variable height and density and containing openings where conditions are shaded, humid and sheltered, with sedges and grasses on wetter ground and heather and bilberry cover on drier areas.

• Control grazing, including that by deer, to maintain open glades without loss of shrubs.

• Fence small areas to allow regeneration and shrubs to develop.

26 • Thin and cut gaps in areas in-filled with regeneration.

Important related species include spotted flycatcher, soprano pipistrelle, brown long-eared bat, red squirrel, pine marten, Scottish wildcat, scaly tooth fungus, grey tooth fungus and juniper.

2.7.4 Related links

• species associated with veteran native pine woodland

• Scotland’s rare tooth fungi management guide

• managing woodlands and their mammals

• saving Scotland’s red squirrels

• habitats and rare, priority, protected species – scaly tooth fungus

• BSBI species accounts – juniper

• managing uplands for juniper

27 3 Upland mixed ashwoods

3.1 Introduction This is woodland on base-rich soils in upland areas. The tree canopy typically includes ash, wych elm or sycamore. Downy birch, rowan, hazel, goat willow, grey willow, eared willow, bird cherry and alder can occur too. Some examples are dominated by hazel. The field layer is typically herb rich.

Most Scottish examples of this priority habitat are on moderate to steep slopes with moist soils below 300m. Associated habitats include other woodland types in the upland oakwoods, upland birchwoods and wet woodland priority habitats, grassland, mires, bracken, cliffs, screes and limestone pavement. The habitat is widespread in Scotland, where it is most common in Argyll, the Inner Hebrides and in an area running from the Breadalbane hills to the eastern Grampians.

3.2 Managing permanent open upland mixed ashwoods Permanent open areas occur where the change in vegetation from woodland to open habitat is due to underlying site factors, such as change in soils (e.g. apparent as areas used as grassland), geology (e.g. cliffs, scree and limestone pavements), water availability (e.g. rivers, mires) or where there is a maintained structure such as a road or ride.

Permanent open areas appear as glades with bracken and herb-rich grassland or irregular woodland margins forming transition habitats along the woodland edge.

3.2.1 Management

• Maintain open space along tracks and use rotational, low-intensity cattle grazing (c. 3 months at 0.1–0.3 animals per ha), preferably in the autumn.

• Don’t fertilise or reseed open areas where there is a botanical interest or where semi-natural vegetation already exits, but allow natural vegetation to develop.

28 • In locations where soil is fertile, the vegetation in open glades used as deer lawns may need to be managed.

• Use managed grazing to control invasion of scrub or hand cut vegetation.

3.2.2 Creation

• When establishing new woodlands, areas that are unplantable as a result of exposure, rock outcrops and water will be left as open space. Don’t plant too close to such features.

• Leave fertile areas open as deer lawns.

• Where possible, rides should be orientated in an east–west direction, as this increases the total hours of sunlight. New rides should be at least 10m wide to prevent shading by canopy when it develops.

• It is not desirable to construct roads through ashwoods.

• Felling one or more corners around a ride intersection or other discrete fellings will renew open spaces.

• When planting next to existing woodland, ensure that open space is included.

3.2.3 Managing niche features

Upland mixed ashwoods with permanent open areas support a range of different niches, including those described below.

Wet ground: ponds, semi-permanent water bodies and areas of poor drainage, e.g. water in wheel ruts and ditches.

• Allow water to collect and avoid draining wet areas or cleaning ditches and ponds.

• Leave material such as harvesting debris or road material if it accumulates nearby.

• Avoid taking heavy machinery over wet soils.

Important related species include great crested newt.

Tree bark (dry): dry bark of ash, elm or sycamore in well-lit, sheltered situations at the woodland edge.

• Carry out selective thinning or planting, weeding and protection to maintain ash, elm and sycamore trees in the stand next to open ground.

• Avoid damage or removal of trees in such situations.

• Manage for open ground conditions.

Important related species include lesser squirrel-tail moss.

Woodland edge/scrub: border between wooded and open habitats providing cover and shelter or an area covered with stunted trees or shrubs.

• Scrub surrounding the open area should be cut or coppiced on a rotation of 8–20 years to create a mosaic of structural diversity and different aged shrubs, providing shelter and habitat stability.

Important related species include great crested newt.

Glades: large open areas with grasses and herbs. A range of vegetation types and heights in a succession from bare ground, short turf, longer vegetation, shrubs and, finally, trees.

• Mow the centre of the glade at least once, or possibly twice, a year to maintain the short turf using the patch method whereby small sections (c. 50m lengths) are mown each time.

• A quarter of tall vegetation should be cut annually and any cuttings produced should be removed to prevent nutrient build-up and the growth of rank weeds.

29 • Use low-intensity cattle grazing (c. 3 months at 0.1–0.3 animals per ha) in autumn; rotate areas grazed to increase diversity and ensure that there are areas where plants can flower and set seed.

Important related species include small pearl-bordered fritillary and pearl-bordered fritillary.

3.2.4 Related links

• species associated with permanent open areas of upland mixed ash woodland

• habitat management for amphibians

• habitat management for reptiles

• pearl bordered fritillary and small pearl-bordered fritillary

3.3 Managing temporary open upland mixed ashwoods Temporary open areas result from disturbance, such as thinning and group felling, cutting along wayleaves and coppicing, and may be short lived – replaced by growth of regenerating trees or regrowth of coppice when released from shading by felling overstorey. The open area may have exposed soil or a humus/litter layer or sparse ground vegetation if densely shaded before disturbance. Depending on site richness, sources of seed available and plant species already occupying the site, open areas can develop species-rich ground vegetation and offer a seed bed for shrubs and tree regeneration. Where ground vegetation is already well developed, this can expand rapidly to fill the site.

3.3.1 Creation

• Re-coppice derelict coppice on sites that have been cut within the last 50 years and where the woodland comprises a mixture of species, such as ash, hazel and others.

• Protect from browsing by deer and sheep. The aim should be to cut some part of the wood once every 5–7 years. Coupes sized between 1ha and 2ha provide adequate habitat diversity. Fell mature stands once advance regeneration appears and the stand is at the end of the rotation (60–80 years). NB: In stands that have not been recently coppiced, such management is often extremely damaging, as rare epiphytes may be removed. This is particularly the case in woods of a more westerly and northerly distribution.

3.3.2 Managing niche features

Upland mixed ashwoods with temporary open areas support several different niches, including those described below.

Glades: large open areas in woodland, with a range of vegetation types and heights in a succession from bare ground, short turf, longer vegetation, shrubs and, finally, trees.

• Develop glades through felling or coppicing shrubs and regenerating trees.

• Use low-intensity cattle grazing (c. 3 months at 0.1–0.3 animals per ha) in autumn. Rotate areas grazed to increase diversity and ensure that there are areas where plants can flower and set seed.

Important related species include pearl-bordered fritillary and small pearl-bordered fritillary.

Rock (dry): rock in a mosaic of ground vegetation, scrub and trees, well lit, warm and sheltered.

• Control rank vegetation and herbaceous plants through grazing (c. 3 months at 0.1–0.3 animals per ha) or, where practical, mow twice yearly.

3.3.3 Related links

• species associated with temporary open areas in upland mixed ash woodland

• pearl-bordered fritillary and small pearl-bordered fritillary

• Identification of pearl-bordered fritillary and small pearl-bordered fritillary

30 3.4 Managing regenerating upland mixed ash woodland This is woodland without an overstorey. Vegetation is composed of tree seedlings (<1m tall), saplings (trees >1m tall and with girth of up to 7cm diameter at breast height) and shrubs. Shrubs are woody plants, usually branching abundantly from the base, >1m tall and usually <5m tall, of the following species:

• blackthorn

• dog rose

• eared willow

• gorse

Other species, such as hawthorn, grey willow, hazel, holly, elder and rowan, may display both shrub and tree forms.

3.4.1 Management

• Control browsing to allow regeneration and shrubs (or coppice shoots) to develop.

• Control invasive, high shade-casting species, such as rhododendron, cherry laurel and Japanese knotweed.

• Do not coppice hazelwoods with no history of coppicing, e.g. in west and north-west Scotland.

3.4.2 Creation

Release established ash regeneration, which often occurs in mature ashwoods (60–80 years old):

• This can be done by felling stands, if timber is mature or if regeneration/shrub structural stage is absent in the landscape, or by allowing canopy tree mortality.

• Protect regeneration from browsing.

• Use small-scale extraction techniques and keep machinery to rides, as soil compaction may change ground flora.

• In dense stands too shady to develop ash understorey (understorey is dominated by wych elm and sycamore), partially fell to initiate ash regeneration.

• Regenerate in several episodes spaced over several decades. Use the shelterwood system (50 ash trees retained per ha, 6m minimum between crowns of adjacent trees) or group felling to create clusters of gaps (gaps 0.1–0.5ha, minimum 30m diameter; enlarge small gaps after 4–5 years).

• Cut large coupes to encourage natural regeneration of shrubs.

• Alternatively, plant species that are desirable components of the woodland habitat and coppice existing shrubs to diversify structure.

• When re-coppicing derelict coppice (only apply to sites where coppice has been cut within the last 50 years; also preferably where a mixture of species is present), cut coupes sized between 1ha and 2 ha, once every 5–7 years and protect from browsing by deer and sheep.

3.4.3 Managing niche features

Regenerating upland mixed ashwoods support a range of different niches, including those described below.

Tree bark (humid): moist sheltered trunks of hazel and willow near water.

• Don’t coppice hazel and willow growing close to water.

• Encourage regeneration of new willow and hazel trees in temporary open habitats following advice for management of structural type ‘regeneration/shrubs’.

31 Important related species include Norwegian specklebelly (Pseudocyphellaria norvegica).

Rock (humid): mossy rocks in willow carr or near water.

• Don’t remove rocks.

• Control vegetation growth by introducing low-intensity grazing (c. 3 months at 0.1–0.3 animals per ha).

Important related species include Norwegian specklebelly (lichen).

Woodland edge/scrub: border between wooded and open habitats providing cover and shelter or an area covered with stunted trees or shrubs.

• The edge or scrub zone should be cut or coppiced on a rotation of 8–20 years to create a mosaic of structural diversity and different aged shrubs.

Important related species include bullfinch.

Glades: large open areas in areas of regeneration and scrub, with a range of vegetation types and heights in a succession from bare ground, short turf, longer vegetation and shrubs.

• Develop glades through cutting shrubs and regenerating trees.

• Use low-intensity cattle grazing (c. 3 months at 0.1–0.3 animals per ha) in autumn; rotate areas grazed to increase diversity and ensure that there are areas where plants can flower and set seed.

Important related species include song thrush, small pearl-bordered fritillary and pearl-bordered fritillary.

3.4.4 Related links

• species associated with regenerating upland mixed ash woodland

• lichens and bryophytes of Atlantic woodland in Scotland

• habitats and rare, priority, protected species – Norwegian specklebelly

• pearl-bordered fritillary and small pearl-bordered fritillary

• Identification of pearl-bordered fritillary and small pearl-bordered fritillary

3.5 Managing thicket or pole stage upland mixed ash woodland Trees and shrubs fill the area and compete directly with other species, ground flora is shaded out and no other plants colonise. Some canopy trees and understorey shrubs die as a result of competition. Trees and shrubs are immature and have not yet started bearing seed/fruit. Trees have a diameter at breast height of >7cm and <20–30cm and are usually above 5m in height.

3.5.1 Management

• It is not possible to maintain a stand in this structural stage indefinitely.

3.5.2 Creation

• Composition and stand density are influenced by management in previous rotations, e.g. through the control of browsing of the regeneration in the previous stand, and during restocking by the choice of species planted.

• High stocking rates (c. >10,000 trees per ha) during planting and regeneration will allow the pole stage to develop more quickly and are likely to increase deadwood provision.

32 3.5.3 Managing niche features

Upland mixed ashwoods with thickets support several different niches, including those described below.

Tree bark (humid): mossy hazel, ash, elm, rowan, oak and willow trunks, in sheltered humid locations under a closed woodland canopy near streams, in ravines and/or high rainfall areas.

• Retain suitable trees.

• Avoid thinning tree canopy shading ravines or streams.

• High humidity is provided by location (coastal), site features, such as ravines and water courses, or local topography.

• Don’t change site drainage by adding new drainage ditches or blocking existing ones.

Important related species include Pseudocyphellaria intricata, Lejeunea mandonii (liverwort) and Norwegian specklebelly (lichen).

Rock (humid): lightly shaded calcareous rock faces in woodland ravines; mossy rocks partially shaded by tree canopy. Sites sheltered, close to water and/or in high rainfall areas.

• Avoid thinning tree canopy shading ravines or streams.

• Don’t change site drainage by adding new drainage ditches or blocking existing ones.

Important related species include Pseudocyphellaria intricata, Lejeunea mandonii (liverwort) and Norwegian specklebelly (lichen).

Trees/bark (dry): smooth bark of ash, hazel and aspen in sheltered locations.

• Manage during earlier phases to ensure that hazel and aspen as well as ash are present. Plant some aspen if absent from the site in the regeneration phase.

3.5.4 Related links

• species associated with thickets of upland mixed ash woodland

• habitats and rare, priority, protected species – Norwegian specklebelly

• lichens and bryophytes of Atlantic woodland in Scotland

3.6 Managing mature upland mixed ashwoods Mature woodland is characterised by trees producing seed/fruit. The crown/canopy is usually spreading and at its maximum development. Canopy die-back (up to 10%) takes place as a result of competition for light and/or wind/snow damage. Ground flora is developed and there is a woodland floor with regenerating trees and shrubs, e.g. hazel. All trees are >5m tall and diameters of trunks at breast height are in the range listed below:

• birches: 20–50cm

• rowan and cherry: 20–75cm

• alder: 20–80cm

• ash: 20–100cm

• elm: 30–150cm

• sycamore: 20–150cm

33 3.6.1 Management

Maintain indefinitely as ‘all-sized’ structure (old growth) by subjecting patches to different intensities of thinning and retaining groups and individual trees in wind-firm locations.

• Avoid cutting hazel and goat willow.

• All-sized structure can be achieved fairly rapidly by singling overgrown coppice plants (not hazel) in areas of derelict coppice (providing stool is still vigorous).

• Control browsing if regenerating species are a desirable part of all-sized structure or in regeneration and later woodland development stages.

3.6.2 Creation

The structure and species composition of the present stand will be influenced by:

• Previous rotation management favouring regeneration of certain species.

• Enrichment planting during regeneration stage; respacing in early pole stage.

• Respacing by selecting two trees >2m apart every 10m, and clearing around these to create a gap the diameter of the surrounding trees.

• Selective thinning in late pole stage further influences species composition of the canopy. An example of such a selective thinning prescription is: identify 200 ash and 200 sycamore stems per ha as dominants, fell all surrounding trees with crowns in competition, and lightly thin the matrix. Repeat every 5–10 years. Apply to areas >2ha.

• For biodiversity benefit, the trees to remain should have irregular forms and snapped limbs. Retain suppressed stems, as these may be older than surrounding trees and have developed a more diverse epiphytic community.

• Don’t introduce too pure standards to stands of hazel, particularly those stands with no history of coppice management.

3.6.3 Managing niche features

Mature upland mixed ashwoods support a range of different niches, including those described below.

Bare ground: visible topsoil in a mosaic of ground vegetation and trees. Low shade levels are due to the open nature of the canopy.

• Use low-intensity cattle grazing (c. 3 months at 0.1–0.3 animals per ha) or mowing to maintain bare ground in areas disturbed during thinning operations.

• Clear regeneration from some areas to prevent over-shading.

Tree bark (dry): dry, rough bark of mainly ash, sycamore and elm or smooth bark of hazel in well-lit, sheltered locations.

• Manage as for all-sized woodland structure to provide species diversity and continuity of open grown trees.

Important related species include spotted flycatcher, red squirrel and lesser squirrel-tail moss.

Tree/bark (humid): bark of mainly hazel and ash, in shaded humid locations, boggy woodlands and/or high rainfall areas.

• Manage as for all-sized woodland structure to provide species diversity and continuity of open grown trees.

• Don’t coppice hazel but allow natural die-back and regrowth.

• Prevent changes in water courses/site drainage.

34 Important related species include white script lichen (Graphis alboscripta), Pseudocyphellaria intricata, Fuscopannaria sampaiana and Bacidia incompta.

Deadwood: cavities in branches and spongy wood inside hollow trees, typically of ash and elm.

• Deadwood target >30m3 per ha. Retain all standing and fallen deadwood.

• Set aside areas of minimal intervention to allow natural build-up of deadwood.

• Formation of cavities takes c. 200 years, but consider accelerating development by wounding (routing) younger trees or inoculating with decay-forming fungi.

Important related species include hawfinch and hazel gloves fungus (Hypocreopsis rhododendri).

Woodland edge/scrub: border between wooded and open habitats providing cover and shelter or an area covered with stunted trees or shrubs.

• Scrub surrounding the open area should be cut or coppiced on a rotation of 8–20 years to create a mosaic of structural diversity and different aged shrubs, providing shelter and habitat stability.

Important related species include hawfinch, wood warbler, pine marten and great crested newt.

Complex understorey with glades: shrubs and regenerating trees forming a layer below the woodland canopy of variable height and density and containing small openings where conditions are sheltered.

• Manage as for all-sized woodland structure.

Important related species include red squirrel and barred tooth-striped (moth).

Wet ground: ponds, semi-permanent water bodies and areas of poor drainage, e.g. water in wheel ruts and ditches.

• Allow water to collect and avoid draining wet areas or cleaning ditches and ponds.

• Leave material such as harvesting debris or road material if it accumulates nearby.

• Avoid taking heavy machinery over wet soils.

Important related species include great crested newt.

Rock (humid): rocks and ground vegetation in humid shaded conditions, e.g. ravines, and stream sides and/or in high rainfall areas.

• Avoid thinning tree canopy where it shades ravines.

• Prevent changes in water courses and site drainage.

• Avoid moving rocks.

Important related species include Pseudocyphellaria intricata, Wilson’s pouchwort (Acrobolbus wilsonii) and Dumortiera hirsuta (liverwort).

Rock (dry): rock, boulders and outcrops. Mossy and well lit or shaded and sheltered. In a mosaic of ground vegetation, with shrubs and trees.

• Avoid moving rocks, and if it is necessary then relocate them in the same orientation and conditions.

• Rank vegetation and herbaceous plants should be controlled by cattle grazing (c. 3 months at 0.1–0.3 animals per ha) and perhaps through mowing (twice yearly) where practicable.

Glades: large open areas in the woodland, with a range of vegetation types and heights in a succession from bare ground, short turf, longer vegetation, shrubs and, finally, trees.

35 • Create by thinning and felling. For example, fell one or more corners around a ride intersection.

• Use low-intensity cattle grazing (c. 3 months at 0.1–0.3 animals per ha) in autumn. Restrict cattle to the glade and rotate areas grazed to increase diversity and ensure that there are areas where plants can flower and set seed.

Important related species include spotted flycatcher.

3.6.4 Related links

• species associated with mature upland mixed ash woodland

• habitat management for amphibians

• habitat management for reptiles

• managing woodlands and their mammals

• action for red squirrels

• habitats and rare, priority, protected species – Wilson's pouchwort

• lichens and bryophytes of Atlantic woodland in Scotland

3.7 Managing veteran upland mixed ash woodland Veteran woodland is characterised by the presence of individual trees that have a large girth.

Minimum diameter at breast height of greater than:

• birch: 50cm

• rowan, cherry and willow: 75cm

• alder: 80cm

• ash: 100cm

• elms and sycamore: 150cm

They also show at least three signs of old growth and decay as listed below:

• major trunk cavities/progressive hollowing

• naturally forming water pools in major forks

• rot/decay sites or holes >5cm diameter

• physical damage to trunks

• bark loss/loose bark

• large quantities of deadwood in the canopy

• sap runs

• crevices in the bark, under branches or in the root plate

• fungal fruiting bodies (e.g. from heart-rotting species)

• epiphytic plants (ferns, mosses, liverworts and lichens)

• high aesthetic interest (e.g. pollard or old coppice stool)

36 3.7.1 Management

• Retain all veteran and ancient trees. Treat each tree individually.

• Undertake as little remedial work as possible, e.g. only lowering crown height to reduce risk of windblow.

• If managed by pollarding in the past, reinstate this with care using a process called ‘retrenchment’. Maintain open canopy around existing trees and do not allow young trees to over-shade them. However, avoid sudden changes by gradually opening up surrounding tree cover. For example, reduce height by pollarding of the surrounding canopy or ring bark surrounding trees to decrease the shade slowly over a period of time.

3.7.2 Creation

• Identify younger trees as replacements and encourage individuals already showing signs of ageing, such as irregular form and snapped limbs (or artificially age trees by wounding them), to have an open growth form by thinning around them. Select those that occupy wind-firm sites.

• Marginal trees and trees growing in inaccessible places and along stream sides should be retained indefinitely.

• Large old coppice stools can be retained by cutting above the level of the last cut.

• Stub trees and pollards, usually on marginal and internal banks, can be maintained by periodic cutting, but only if the nearby woodland is opened up at the same time.

3.7.3 Managing niche features

Veteran upland mixed ashwoods support a range of different niches, including those described below.

Tree bark (humid): ash, elm, oak and hazel with mossy or wounded bark in sheltered, humid locations.

• Avoid diversion of watercourses or interventions that affect site drainage.

• Minimise mortality of trees retained as replacements and encourage frequent natural regeneration of ash and elm.

• Don’t coppice hazel, but allow natural die-back and regrowth.

Important related species include Bacidia incompta (lichen), Fuscopannaria sampaiana (lichen) and Leptogium cochleatum (lichen).

Tree bark (dry): rough, dry bark of well-lit trees, particularly ash, elm and sycamore, and smooth bark of hazel.

• Avoid damage to hollow trunks or removal of limbs with bark features.

• Minimise mortality of trees retained as replacements and encourage frequent natural regeneration events to maintain continuity and diversity of tree species.

Important related species include spotted flycatcher and lesser squirrel-tail moss (lichen).

Deadwood: spongy wood inside hollow trees, typically of ash and elm, often near water.

• Manage as for veteran and ancient trees (see management of ‘veteran and ancient’ structure stage).

• Retain all sources of fallen and standing deadwood (target >30m3 per ha.).

• Move towards continuity of deadwood resources, especially of large logs and snags.

Important related species include hazel gloves fungus.

Rock (dry): calcareous rock, boulders and outcrops; dry, mossy and shaded or well lit.

• Avoid moving rocks, and if it is necessary then relocate them in the same orientation and conditions.

37 • Rank vegetation and herbaceous plants should be controlled by cattle grazing (c. 3 months at 0.1–0.3 animals per ha) and perhaps through mowing (twice yearly) where practicable.

Rock (humid): shaded, mossy calcareous boulders, in humid locations stream sides and/or in high rainfall areas.

• Avoid moving rocks, and if it is necessary then relocate them in the same orientation and conditions.

• Avoid diversion of watercourses or interventions that affect site drainage.

• Rank vegetation and herbaceous plants should be controlled by cattle grazing (c. 3 months at 0.1–0.3 animals per ha) and perhaps through mowing (twice yearly) where practicable.

Important related species include Dumortiera hirsuta (liverwort).

3.7.4 Related links

• species associated with veteran upland mixed ash woodlands

38 4 Upland birchwoods

4.1 Introduction This is woodland in which downy birch or silver birch, or both, is dominant in the canopy. It occurs in places where the climate is too cold for oak or ash to attain abundance or dominance, though some other small to medium-sized trees and shrubs can occur as associates of the birch, especially rowan, aspen, hazel, eared willow and juniper.

This woodland occurs on well-drained to rather poorly drained acidic soils in the Scottish Highlands and the Hebrides. Stands of birch further south are best regarded as cyclical or successional stages of other types of woodland, especially those belonging to the upland oakwood priority habitat.

The structural stages listed below are important for wildlife, resulting in a set of conditions that are required by a range of species.

4.2 Managing permanent open upland birchwoods Permanent open areas occur where the change in vegetation from woodland to open habitat is due to underlying site factors, such as change in soils (e.g. areas of peat), geology (e.g. scree and cliffs), water availability (e.g. mires) or where there is a maintained structure, such as road or ride, or downfalls for red deer in the uplands so they can reach wintering grounds. Woodland glades create warm, sheltered openings.

4.2.1 Management

• Use low-intensity grazing to maintain openness and diversity in composition and structure of vegetation. Mechanical cutting might be needed if there are prolonged periods without grazing.

• To control dense vegetation, hand cutting is recommended, but limited use of herbicides is possible where grasses are dominant.

• Don’t fertilise because of impacts this can have on semi-natural vegetation composition.

39 • Don’t drain damp areas or mires. Remove rhododendron, as it can shade out ground vegetation.

4.2.2 Creation

• When establishing new woodlands, areas that are unplantable, e.g. as a result of exposure, rock outcrops, water or different land use, will be left as open space. Don’t plant too close to such features.

• When planting next to existing woodland, ensure that open space is included.

• New rides should be at least 10m wide to prevent shading by canopy when it develops and west–east rides should be at least 1.5 times wider than the height of the trees on the south side – 10–30m. Rides should meander though the forest compartments, as straight rides can act as wind tunnels.

• Development of rides and glades could occur through coppicing or felling regenerating trees and scrub, e.g. felling one or more corners around a ride intersection or felling woodland along rides to create a network of long glades.

• NB: Do not clear significant areas of woodland, particularly on ancient woodland sites.

4.2.3 Managing niche features

Upland birchwoods with permanent open areas support a range of different niches, including those described below.

Woodland edge/scrub: border between wooded and open habitats providing cover and shelter or an area covered with stunted trees or shrubs.

• The edge or scrub zone should be cut or coppiced on a rotation of 8–20 years to create a mosaic of structural diversity and different aged shrubs.

Important related species include great crested newt and argent and sable (moth).

Wet ground: ponds, semi-permanent water bodies and areas of poor drainage, e.g. water in wheel ruts and ditches.

• Allow water to collect and avoid draining wet areas or cleaning ditches and ponds.

• Leave material such as harvesting debris or road material if it accumulates nearby.

• Avoid taking heavy machinery over wet soils.

Important related species include great crested newt.

Glades: large open areas with a range of vegetation types and heights in a succession from bare ground, short turf, longer vegetation, shrubs and, finally, trees.

• Use cattle grazing (low intensity; c. 3 months at 0.1–0.3 animals per ha), preferably in autumn, to maintain open conditions and variable vegetation cover.

• Alternatively, cut up to 25% of the tall herb zone on rotation each year (July–August) to create a mosaic of tall herbs of at least four different ages.

• Clear dense regeneration from some areas to prevent over-shading, but allow juniper and rowan to establish.

Important related species include pearl-bordered fritillary, small pearl-bordered fritillary and juniper.

Tree/bark (dry): smooth bark of aspen trees at woodland edge.

• Carry out selective thinning or planting, weeding and protection to maintain aspen in the stand next to open ground.

• Avoid damage or removal of limbs with bark features, such as crevices, wounds and rain tracks.

40 4.2.4 Related links

• species associated with permanent open areas of upland birch woodland

• habitat management for amphibians

• habitat management for reptiles

• BSBI species accounts – juniper

• managing uplands for juniper

• pearl-bordered fritillary and small pearl-bordered fritillary

• Identification of pearl-bordered fritillary and small pearl-bordered fritillary

4.3 Managing temporary open upland birch woodland Temporary open areas result from disturbance such as group felling and respacing, may be short lived and perhaps replaced by regenerating trees. Open areas may have exposed soil or a humus/litter layer or sparse ground vegetation if densely shaded before disturbance. Depending on site richness, sources of seed available and plant species already occupying the site, open areas can develop vegetation cover, such as bracken and grass or trees from exiting seedlings, or offer a seed bed for shrubs and trees such as birch. Where ground vegetation is already well developed, this can expand rapidly to fill the site.

4.3.1 Management

• Encourage low-intensity browsing and grazing.

• Control weeds through hand cutting around planted birch. Limited use of herbicides is acceptable, especially where grasses are dominant.

• Removal of rhododendron is a priority.

• Don’t drain wet areas.

• Don’t apply fertilisers.

4.3.2 Creation

• Fell mature stands at the end of rotation (when birch stand is at least 60 years old).

• Respace thick clumps of regeneration (between 1.5m and 4m in height) and carry out early and heavy thinning of stands at pole stage.

• Coppice young birch (less than 10–15 years old), cutting along wayleaves.

4.3.3 Managing niche features

Upland birchwoods with temporary open areas support several different niches, including those described below.

Woodland edge/scrub: border between wooded and open habitats providing cover and shelter or an area covered with stunted trees or shrubs. Wet areas can contain bog myrtle.

• Cut or coppice the scrub zone on a staggered rotation of 8–20 years to create a mosaic of structural diversity and different aged shrubs including birch.

• Don’t cut bog myrtle.

Important related species include argent and sable (moth).

41 Glades: large open areas in the woodland, with a range of vegetation types and heights in a succession from bare ground, short turf, longer vegetation, shrubs and, finally, trees.

• Use cattle grazing (low intensity for c. 3 months at 0.1–0.3 animals per ha), preferably in autumn, to prolong open conditions and variable vegetation cover.

Important related species include pearl-bordered fritillary and small pearl-bordered fritillary.

4.3.4 Related links

• species associated with temporary open areas of upland birch woodland

• pearl-bordered fritillary and small pearl-bordered fritillary

• Identification of pearl-bordered fritillary and small pearl-bordered fritillary

4.4 Managing regenerating upland birch woodland This is woodland without an overstorey. Vegetation is composed of tree seedlings (<1m tall), saplings (trees >1m tall and with girths of up to 7cm diameter at breast height) and shrubs. Birch can produce vigorous regeneration.

Shrubs are woody plants, usually branching abundantly from the base, >1m tall and usually <5m tall, of the following species, which are all natural components of birch woodland:

• juniper

• eared willow

• birch

• Scots pine

• aspen

• willow

4.4.1 Management

• Improve establishment of birch regeneration by hand cutting weeds.

• Where grasses are dominant, limited use of herbicides is recommended.

• Remove regenerating Sitka spruce and western hemlock.

• Rhododendron removal is essential.

• Prevent browsing in areas that have been re-coppiced.

4.4.2 Creation

• Limit disturbance of open ground on the edges of woodland within 50m of mature trees through grazing and the appropriate timing of its removal or by superficial scarification in areas where grazing is controlled.

• Avoid creating large areas of bare soil, as this can reduce seedling survival.

• Felling, with its associated ground disturbance, can stimulate regeneration. Coupes need to be more than 0.5ha, between 30m and 80m wide (minimum of three times the height of surrounding trees). In larger coupes, retain a scatter of mother trees at c. 25 stems per ha.

• Dense bracken can prevent any regeneration. Extensive stands may require herbicide treatment.

42 • Felling to promote regeneration in open degenerate woods is unnecessary and undesirable.

• Control browsing in mature woodlands if the species arising by regeneration are desired in the regeneration/shrub habitat.

• When natural regeneration is absent, plant species that are desirable components of the woodland habitat. Plant groups of birch at 2m spacing with gaps of variable size between groups. Plant aspen and juniper and maintain low deer pressure for successful establishment, particularly of aspen.

4.4.3 Managing niche features

Regenerating upland birchwoods support several different niches, including those described below.

Complex understorey with glades: shrubs, small trees and regenerating trees forming a layer below the woodland canopy of variable height and density and containing small openings where conditions are shaded, humid and sheltered with grasses (and sedges on wetter ground) and heather and bilberry cover in drier areas.

• Clear regeneration from some areas to create glades.

• Continue some disturbance (low-intensity cattle grazing) to cause patchy regeneration.

Important related species include song thrush.

Woodland edge/scrub: border between wooded and open habitats providing cover and shelter or an area covered with stunted trees or shrubs. Wet areas can contain bog myrtle.

• Cut or coppice scrub on a staggered rotation of 8–20 years to create a mosaic of structural diversity and different aged shrubs including birch.

• Don’t cut bog myrtle.

Important related species include otter and argent and sable (moth).

Glades: large open areas in the woodland, with a range of vegetation types and heights in a succession from bare ground, short turf, longer vegetation, shrubs and, finally, trees.

• Use cattle grazing (low intensity for c. 3 months at 0.1–0.3 animals per ha), preferably in autumn, to maintain open conditions and variable vegetation cover (e.g. prevent dense bracken growth).

Important related species include pearl-bordered fritillary and small pearl-bordered fritillary.

4.4.4 Related links

• species associated with regenerating upland birch woodland

• pearl-bordered fritillary and small pearl-bordered fritillary

• Identification of pearl-bordered fritillary and small pearl-bordered fritillary

4.5 Managing mature upland birch woodland Mature woodland is characterised by trees producing seed/fruit. The crown/canopy is spreading and at maximum development.

There is canopy die-back (up to 10%) as a result of competition for light and/or wind/snow damage. The ground flora is developed and there is a woodland floor with shrubs and regenerating trees. Birch is a minimum of 60 years old. All trees are greater than 5m tall and diameters of trunks at breast height are in the range listed below:

• birch and aspen: 20–50cm

43 • rowan: 20–75cm

• Scots pine: 35–80cm

• oaks: 30–100cm

4.5.1 Management

Maintain indefinitely as ‘all-sized’ structure (old growth) by thinning to reduce the basal area to 10–20m2 per ha.

• Heavy and early thinning will allow a shrub layer and ground vegetation to develop and provide enough light for even shade-intolerant species to establish and grow.

• Control browsing if species arising by regeneration are desired.

• If a uniform woodland structure is due to present and historical grazing pressure preventing understory development, diversify by increasing deer control and scarifying. Otherwise vary the intensity of thinning and retain some unthinned clumps to encourage structural diversity.

• Trees selected to remain should include those with irregular forms and snapped limbs. Suppressed stems should not be automatically removed, as these may be older than surrounding trees and have developed a more diverse epiphytic community.

4.5.2 Creation

The structure and species composition of the present stand will be influenced by:

• practices in previous rotations favouring regeneration of species (birch, due to its shade intolerance, is best allowed to develop in small groups during the woodland cycle)

• enrichment planting during the regeneration stage respacing of trees occurring in thick clumps of regeneration at early pole stage, when trees are between 1.5m and 2.5m in height to prevent snow break and to allow the crown to develop

• selective thinning in late pole stage by variable density thinning, every 5–10 years, to remove trees from the upper canopy, leaving c. 300 birch stems per ha as dominants and favouring minor species

4.5.3 Managing niche features

Mature upland birchwoods support a range of different niches, including those described below.

Wet ground: ponds, semi-permanent water bodies and areas of poor drainage, e.g. water in wheel ruts and ditches.

• Allow water to collect and avoid draining wet areas or cleaning ditches and ponds.

• Leave material such as harvesting debris or road material if it accumulates nearby.

• Avoid taking heavy machinery over wet soils

Important related species include great crested newt.

Tree bark (dry): smooth bark, typically of birch and aspen, in generally well-lit locations.

• Selectively thin to retain aspen and birch trees in well-lit conditions and to encourage growth of replacement aspen trees.

Important related species include spotted flycatcher, soprano pipistrelle and brown long-eared bat.

Deadwood: large deadwood (standing or fallen) generally created through natural tree ageing and the colonisation of fungi, lichen and saproxylic invertebrates.

• Leave some felled and lying deadwood after harvesting as well as all standing deadwood.

44 • Create snags and fallen deadwood where <10% of stems in the stand contain deadwood.

• Leave large limbs in situ and heap up smaller material.

• Concentrate deadwood in areas where it can be grouped with live stems and native trees in shaded and moist conditions.

• Set aside some areas of minimal intervention to allow a natural build-up of deadwood. Target 20m3 per ha.

Woodland edge/scrub: border between wooded and open habitats providing cover and shelter or an area covered with stunted trees or shrubs. Wet areas can contain bog myrtle.

• Scrub could be cut or coppiced on a staggered rotation of 8–20 years to create a mosaic of structural diversity and different aged shrubs including birch.

• Don’t cut bog myrtle.

Important related species include great crested newt.

Complex understorey with glades: shrubs and regenerating trees forming a layer below the woodland canopy of variable height and density and containing small openings where conditions are shaded, humid and sheltered with grasses (and sedges on wetter ground) and heather and blueberry cover in drier areas.

• Manage as for all-sized woodland structure.

• Don’t drain wet/boggy areas.

Important related species include black grouse, soprano pipistrelle, brown long-eared bat and Scottish wildcat.

Tree bark (humid): smooth or mossy bark typically of hazel, birch, rowan and holly in shaded, humid locations (close to water, boggy woodlands or in high rainfall areas).

• Manage for all-sized structure and diverse tree composition including hazel, holly and rowan (as above). High humidity of the niche is provided by location (coastal), site features, such as ravines and water courses, or local topography.

• Avoid changing the drainage of the site (adding/blocking drains).

Glades: large open areas in the woodland, with a range of vegetation types and heights in a succession from bare ground, short turf, longer vegetation, shrubs and, finally, trees.

• Use cattle grazing (low intensity for c. 3 months at 0.1–0.3 animals per ha), preferably in autumn, to maintain open conditions and variable vegetation cover, e.g. to prevent dense bracken growth.

Important related species include spotted flycatcher, juniper, song thrush and Scottish yellow splinter (cranefly).

Rock (humid): rocks and ground vegetation in humid, shaded conditions, e.g. ravines, flushes with tree canopy cover.

• Avoid thinning tree canopy where it shades ravines or flushes.

• Prevent changes in the site drainage. Don’t add new drainage ditches or block existing ones.

• Use low-intensity cattle grazing (3 months at 0.1–0.3 animals per ha) in autumn to control rank growth grasses and herbaceous vegetation.

• Hand cut dense regeneration, such as rhododendron or beech, which may occur in more westerly woods.

Important related species include Wilson’s pouchwort.

4.5.4 Related links

• species associated with mature upland birch woodland

45 • habitat management for amphibians

• habitat management for reptiles

• BSBI species accounts – juniper

• managing uplands for juniper

• habitats and rare, priority, protected species – Wilson's pouchwort

• lichens and bryophytes of Atlantic woodland in Scotland

4.6 Managing veteran and ancient upland birch woodland Veteran forest will include trees with minimum diameters at breast height of greater than:

• birches: 50cm

• rowan and holly: 75cm

• Scots pine: 80cm

• oaks: 100cm

It is characterised by the presence of individual trees that have a large girth and which show at least three of the following signs of old growth and decay:

• major trunk cavities/progressive hollowing

• naturally forming water pools in major forks

• rot/decay holes >5cm diameter

• rot/decay sites, physical damage to trunks

• bark loss/loose bark

• large quantities of deadwood in the canopy

• sap runs

• crevices in the bark, under branches or in the root plate

• fungal fruiting bodies (e.g. from heart-rotting species)

• epiphytic plants (ferns, mosses, liverworts and lichens)

• high aesthetic interest (e.g. pollard or old coppice stool)

4.6.1 Management

• Retain all veteran and ancient trees. Treat each tree individually, undertaking as little remedial work as possible, e.g. lowering crown height to reduce risk of windblow.

• Maintain open canopy around existing trees and do not allow young trees to over-shade them. However, avoid sudden changes by gradually opening up surrounding tree cover. For example, reduce the height of the surrounding canopy or ring bark surrounding trees to decrease the shade slowly over a period of years.

4.6.2 Creation

• Identify younger trees as replacements, for example by retaining some mother trees in shelterwood and thinning to develop large, wind-firm trees.

46 • Allow some groups of trees to grow longer than might be commercially desirable, selecting individuals already showing signs of ageing, such as irregular form and snapped limbs (or artificially age the trees by wounding them), and encourage an open growth form by thinning around them during management of mature woodlands.

• Marginal trees and trees growing in inaccessible corners and along stream sides should be retained indefinitely.

4.6.3 Managing niche features

Veteran and ancient upland birchwoods support a range of different niches, including those described below.

Tree bark (dry): crooks in tree limbs, flaking or fissured bark creating nesting sites.

• Retain limbs with cavities and bark features, such as crevices.

• Minimise mortality of trees retained as replacements.

• Encourage frequent natural regeneration events to reduce age gap between cohorts, as the time between the regeneration of trees and the formation of tree cavities is long (e.g. oak more than 200 years).

Important related species include spotted flycatcher.

Deadwood: large deadwood (standing or fallen) generally created through natural tree ageing and the colonisation of fungi, lichen and saproxylic invertebrates.

• Leave some felled and lying deadwood after thinning as well as standing deadwood.

• Leave large limbs in situ and heap up smaller material. Leave in shaded and moist conditions.

• Set aside some areas of minimal intervention to allow natural build-up of deadwood.

• Deadwoord target >30m3 per ha.

Important related species include great crested newt.

Complex understorey with glades: shrubs and regenerating trees forming a layer below the woodland canopy of variable height and density and containing small openings where conditions are shaded, humid and sheltered with grasses (and sedges on wetter ground) and heather and bilberry cover in drier areas.

• Fence small areas to allow regeneration and shrubs to develop. Carry out thinning and cut gaps in areas in-filled with regeneration consistent with management of ancient and veteran trees (above).

Tree/bark (humid): smooth or mossy bark typical of hazel, birch, rowan and holly in shaded, humid locations (close to water, boggy woodlands or in high rainfall areas).

• Manage for continuity of trees and a diverse tree species composition including hazel, holly and rowan.

• The high humidity of the niche is provided by location, site features, such as ravines and water courses, or local topography.

• Avoid changing the drainage of the site (adding/blocking drains).

Important related species include brown long-eared bat and soprano pipistrelle.

Glades: large open areas in the woodland, with a range of vegetation types and heights in a succession from bare ground, short turf, longer vegetation, shrubs and, finally, trees.

• Use cattle grazing (low intensity for c. 3 months at 0.1–0.3 animals per ha), preferably in autumn, to maintain open conditions and variable vegetation cover (e.g. to prevent dense bracken growth).

Important related species include spotted flycatcher, juniper, great crested newt, Scottish yellow splinter (cranefly) and fused tooth fungus (Phellodon confluens).

47 Woodland edge/scrub: border between wooded and open habitats providing cover and shelter or an area covered with stunted trees or shrubs.

• Scrub could be cut or coppiced on a rotation of 8–20 years to create a mosaic of structural diversity and different aged shrubs.

Important related species include brown long-eared bat, soprano pipistrelle and Scottish wildcat.

4.6.4 Related links

• species associated with veteran upland birch woodlands

• habitat management for amphibians

• habitat management for reptiles

• BSBI species accounts – juniper

• managing uplands for juniper

48 5 Upland oakwoods

5.1 Introduction This is woodland on well-drained to rather poorly drained, acidic to neutral soils in the upland parts of Britain, where sessile oak or pedunculate oak forms at least 30% of the canopy cover. Other tree and shrub species occur commonly, especially silver birch, downy birch, rowan, hazel and holly.

Most Scottish examples of this priority habitat are on moderate to steep slopes below 300m, with well-drained brown earth or podzol soils. This priority habitat can occur in mosaics with the upland birchwood, upland mixed ashwood and wet woodlands priority habitats, as well as with open habitats including bracken, heath, cliffs, screes and acid grassland. The habitat is widespread in Scotland and in upland areas of Britain generally.

5.2 Managing permanent open upland oakwoods Permanent open areas occur where the change in vegetation from woodland to open habitat is due to underlying site factors, such as change in soils (e.g. apparent as areas of acid grassland or bracken), geology (e.g. cliffs and scree), water availability (e.g. mires and streams) or where there is a maintained structure, such as a road or ride, or in the uplands downfalls for red deer so they can reach wintering grounds. Poorly stocked woodlands where grazing continues will have plenty of open spaces. Bracken, bramble and grasses often grow strongly in open patches.

5.2.1 Management

• Use low-intensity grazing and browsing to maintain diversity in composition and structure and reduce shading levels.

• Avoid regular mechanical cutting of ground vegetation, as this often results in impoverishment to a grassy mat.

• To control dense bramble, hand cutting, preferably delayed until late summer, is recommended.

• Don’t fertilise open areas.

49 5.2.2 Creation

• When establishing new woodlands, areas that are unplantable, e.g. due to exposure, rock outcrops, water or different land use, will be left as open space. Don’t plant too close to such features.

• When planting next to existing woodland, ensure that open space is included.

• New rides should be at least 10m wide to prevent shading by canopy when it develops, and west–east rides should be at least 1.5 times wider than the height of the trees on the south side, which is likely to be at least 30m in deciduous high forest.

5.2.3 Managing niche features

Upland oakwoods with permanent open areas support a range of different niches, including those described below.

Wet ground: ponds, semi-permanent water bodies and areas of poor drainage, e.g. water in wheel ruts and ditches.

• Allow water to collect and avoid draining wet areas or cleaning ditches and ponds.

• Leave material such as harvesting debris or road material if it accumulates nearby.

• Avoid taking heavy machinery over wet soils.

Important related species include great crested newt.

Tree bark (dry): well-lit and dry fissured bark of oak in sheltered locations.

• Maintain open grown oak trees at the edge of open areas.

• Manage for continuity of trees in similar locations.

Tree bark (humid): bark on trees at the woodland edge but in humid locations (i.e. close to water, ravines, areas of high tree density or in high rainfall areas).

• The high humidity of the niche is provided by location (e.g. areas of high rainfall), site features, such as high stocking density, ravines and water courses, or local topography.

• Avoid changing the drainage of the site (e.g. by adding/blocking drains) or changing density of trees through felling.

Woodland edge/scrub: border between wooded and open habitats providing cover and shelter or an area covered with stunted trees or shrubs. Bog myrtle may occur on wetter areas.

• The edge or scrub zone should be cut or coppiced on a staggered rotation of 8–20 years to create structural diversity and a mosaic of different aged shrubs.

• Don’t cut bog myrtle.

Important related species include great crested newt and argent and sable (moth).

Glades: large open areas with a range of vegetation types and heights in a succession from bare ground, short turf, longer vegetation, shrubs and, finally, trees.

• Use low-intensity cattle grazing (c. 3 months at 0.2–0.4 animals per ha) in autumn to prevent high levels of shade and dense bracken forming.

• Rotate grazing so that plants in one-third of the area are left ungrazed and can flower and set seed each year. The infrequent disturbance leads to increased plant diversity.

Important related species include pearl-bordered fritillary, small pearl-bordered fritillary and juniper.

Bare ground: visible topsoil in a mosaic of ground vegetation and wet due to high precipitation or poor drainage.

50 • Use low-intensity cattle grazing (c. 3 months at 0.2–0.4 animals per ha) in autumn to help maintain bare ground in areas previously disturbed.

• Clear regeneration from some areas to prevent over-shading.

Important related species include slow worm.

5.2.4 Related links

• species associated with permanent open areas in upland oak woodland

• habitat management for amphibians

• habitat management for reptiles

• BSBI species accounts – juniper

• managing uplands for juniper

• pearl-bordered fritillary and small pearl-bordered fritillary

• Identification of pearl-bordered fritillary and small pearl-bordered fritillary

5.3 Managing temporary open upland oakwoods Temporary open areas result from disturbance, such as group felling and thinning, and may be short lived, and may, for example, be replaced by regenerating trees. Open areas may have exposed soil or a humus/litter layer or sparse ground vegetation if densely shaded before disturbance. Depending on site richness, sources of seed available and plant species already occupying the site, open areas can develop vegetation cover, such as bracken and grass or trees, from existing seedlings, or offer a seed bed for shrubs and trees, e.g. bramble and birch. Where the ground vegetation is already well developed, this can expand rapidly to fill the site.

5.3.1 Creation

• Discrete fellings will renew open spaces and can occur as part of regeneration fellings when woodland is mature (c. 150 years).

• Groups of at least three mature oak trees should be cut.

• Fellings should not cover more than 15% of the woodland area.

• Large areas should not be clear-felled.

• Rhododendron and cherry laurel can extinguish ground vegetation and these species should be removed by cutting.

5.3.2 Managing niche features

Upland oakwoods with temporary open areas support several different niches, including those described below.

Woodland edge/scrub: border between wooded and open habitats providing cover and shelter or areas covered with stunted trees or shrubs. Wet areas can contain bog myrtle.

• The scrub zone should be cut or coppiced on a staggered rotation of 8–20 years to create structural diversity and a mosaic of different aged shrubs including birch.

• Don’t cut bog myrtle.

Important related species include argent and sable (moth).

51 Glades: large open areas in the woodland, with grasses such as Molinia and herbs. A range of vegetation types and heights in a succession from bare ground, short turf, longer vegetation, shrubs and, finally, trees. Can develop dense bracken cover.

• Use low-intensity cattle grazing (c. 3 months at 0.2–0.4 animals per ha) in autumn to prevent areas in-filling with too rapid regeneration and dense bracken forming.

Important related species include pearl-bordered fritillary and small pearl-bordered fritillary.

5.3.3 Related links

• species associated with temporary open areas in upland oak woodland

• pearl-bordered fritillary and small pearl-bordered fritillary

• Identification of pearl-bordered fritillary and small pearl-bordered fritillary

5.4 Managing regenerating upland oakwoods This is woodland without an overstorey. Vegetation is composed of tree seedlings (<1m tall), saplings (trees >1m tall and with girths of up to 7cm diameter at breast height) and shrubs. Shrubs are woody plants usually branching abundantly from the base, >1m tall and usually <5m tall, of the following species:

• juniper

• bramble

• dog rose

• gorse

• broom

Other species, such as hawthorn, hazel, holly and rowan, may display both shrub and tree forms.

5.4.1 Management

• If necessary, improve establishment of oak regeneration by spot weeding (1m diameter circles) using herbicides around plants every 3–4 years.

• Remove rhododendron and cherry laurel by hand cutting.

• Prevent browsing in areas that have been re-coppiced.

• In areas with high deer numbers, control measures should be implemented to prevent overgrazing.

5.4.2 Creation

• Use felling by cutting groups of at least three oak trees in mature stands at the end of their rotation (c. 150 years and preferably once advance regeneration appears). Fellings should not cover more than 15% of the woodland area.

• Avoid compaction with machinery, as a change in ground flora composition to one dominated by species preferring wet conditions may result.

• Felling should not be necessary in woodlands that are already poorly stocked, with abundant open space on suitable (i.e. well-drained) soils, but browsing levels may need to be controlled by, for example, temporarily fencing areas.

52 • Dense bracken can prevent any regeneration and may require control. Herbicides can be used if necessary, but avoid moist areas, near streams and where other fern species will be affected.

• In the absence of natural regeneration, plant species that are desirable in the woodland.

• Selective removal of beech and sycamore during thinning operations carried out during management of previous rotations should ensure that these species don’t dominate shrub habitat.

• Only coppice sites that have a recent history of this management.

5.4.3 Managing niche features

Regenerating upland oakwoods support several different niches, including those described below.

Woodland edge/scrub: border between wooded and open habitats providing cover and shelter or an area covered with stunted trees or shrubs. Wet areas can contain bog myrtle.

• The scrub zone should be cut or coppiced on a staggered rotation of 8–20 years to create structural diversity and a mosaic of different aged shrubs including birch.

• Don’t cut bog myrtle.

Important related species include otter and argent and sable (moth).

Glades: large open areas in the woodland, with grasses such as Molinia and herbs. A range of vegetation types and heights in a succession from bare ground, short turf, longer vegetation, shrubs and, finally, trees. Can develop dense bracken cover.

• Use low-intensity cattle grazing (c. 3 months at 0.2–0.4 animals per ha) in autumn to prevent areas in-filling with regeneration too rapidly and dense bracken forming.

• Glades could be developed through coppicing shrubs and trees that are regenerating.

Important related species include song thrush, pearl-bordered fritillary and small pearl-bordered fritillary.

5.4.4 Related links

• species associated with regenerating upland oak woodland

• pearl-bordered fritillary and small pearl-bordered fritillary

• Identification of pearl-bordered fritillary and small pearl-bordered fritillary

•

5.5 Managing thickets or copses in upland oakwoods Trees and shrubs fill the area and are in competition with each other. Ground flora is shaded out and there is no colonisation by other plants. Some trees in the canopy and shrubs in the understorey die as a result of competition. Trees and shrubs have not yet started bearing seed/fruit (immature). The trees have a diameter at breast height of ≥7cm and < 20–30cm and are usually above 5m in height.

5.5.1 Management

It is difficult to perpetuate stands at thicket or pole stage unless woodland is dominated by one species and is on a very uniform site. Management of this structural type is usually aimed at influencing the composition and structure of a ‘mature’ woodland structure type.

5.5.2 Creation

Composition and stand density are influenced by site management in previous rotations, e.g. by control of browsing of the regeneration in the previous stand and during restocking (the choice of species planted). High stocking rates (c.

53 >10,000 trees per ha) during the planting or regeneration phase will allow this structure to develop more quickly and are likely to increase deadwood provision.

5.5.3 Managing niche features

Upland oakwoods with thickets support several different niches, including those described below.

Tree bark (humid): mossy bark of oak trees, partially shaded with no direct rain in humid locations, e.g. ravines, stream sides with dense stands and tree canopy cover, and/or in high rainfall areas.

• Retain suitable trees.

• Avoid thinning the stand and tree canopy where it shades ravines or streams.

• The high humidity of the niche is provided by location, site features such as ravines and water courses or local topography.

• Avoid changes in the site drainage. Don’t add new drainage ditches or block existing ones.

• Hand cut dense regeneration such as rhododendron or beech, which may occur in more westerly woods.

Important related species include Lejeunea mandonii (liverwort).

Rocks (humid): rocks in humid, shaded conditions, e.g. ravines, stream sides with dense tree canopy cover and/or in high rainfall areas.

• Avoid thinning the tree canopy where it shades ravines or streams.

• Prevent changes in site drainage. Don’t add new drainage ditches or block existing ones.

• Use low-intensity cattle grazing (c. 3 months at 0.2–0.4 animals per ha) in summer to control rank growth of grasses and herbaceous vegetation

Important related species include Lejeunea mandonii (liverwort).

5.5.4 Related links

• species associated with thickets of upland oak woodland

5.6 Managing mature upland oakwoods Mature woodland is characterised by trees producing seed/fruit. The crown/canopy is usually spreading and at its maximum development. Canopy die-back (up to 10%) occurs as a result of competition for light and/or wind/snow damage. Ground flora is developed and there is a woodland floor with regenerating trees and shrubs.

All trees are greater than 5m tall and diameters of trunks at breast height are in the range listed below:

• birches: 20–50cm

• aspen: 20–50cm

• rowan: 20–75cm

• oaks: 30–100cm

• sycamore: 20–150cm

• beech: 30–150cm

Most upland oakwoods were coppiced until the late 19th to mid-20th centuries and therefore comprise even-aged stands, 50–150 years old, with little or no younger growth, a high density of stems, and many multi-stemmed trees.

54 5.6.1 Management

Maintain indefinitely as ‘all-sized’ structure (old growth) in overgrown coppice woods by singling (reducing multi-stemmed trees to a single stem), followed by further thinning on a 5–10 year cycle.

• Thinning should aim to reduce the basal area to 10–20m2 per ha (averaged over the stand), providing enough light for shade-intolerant species (including oak) to establish and grow and allowing a multi-layer canopy to develop.

• Interventions should fell groups of at least three mature oak trees but be limited to 15% of the woodland area. Trees selected to remain should include those with irregular forms and snapped limbs. Suppressed stems should not be automatically removed, as these may be older than surrounding trees and have developed a more diverse epiphytic community.

5.6.2 Creation

The structure and species composition of the present stand will be influenced by:

• Previous rotation management favouring regeneration of species.

• Enrichment planting during regeneration stage.

• Respacing in early pole stage.

• Heavy and early thinning allowing a shrub layer to persist or develop and retaining vigorous ground vegetation in the late pole stage.

• Species composition of the high canopy can be further influenced by selective thinning when the stand is in late pole stage. This involves removal of trees from the upper canopy: identify 150 stems of oak per ha and 300 birch stems per ha as dominants in the stand. Mark and fell all those surrounding with crowns in competition with the chosen dominants.

• Lightly thin the matrix. Repeat every 5–10 years or otherwise vary the intensity of thinning and retain some unthinned clumps to encourage structural diversity.

• Aim to reduce the dominance of beech and sycamore so that they are only a small part of the future canopy.

5.6.3 Managing niche features

Mature upland oakwoods support a range of different niches, including those described below.

Wet ground: ponds, semi-permanent water bodies and areas of poor drainage, e.g. water in wheel ruts and ditches.

• Allow water to collect and avoid draining wet areas or cleaning ditches and ponds.

• Leave material such as harvesting debris or road material if it accumulates nearby.

• Avoid taking heavy machinery over wet soils.

Important related species include noctule and great crested newt.

Tree bark (dry): dry, well-lit buttresses and bark fissures of oak; dry, well-lit and generally smooth bark of trunks or twigs of willow, hazel, holly, rowan and birch.

Manage as for all-sized structure to maintain open grown trees and a diverse tree composition.

Important related species include spotted flycatcher, pine marten, brown long-eared bat, soprano pipistrelle, red squirrel, noctule, grey tooth fungus, velvet tooth fungus (Hydnellum spongiosipes), bitter tooth fungus and Schismatomma graphidioides (lichen).

Deadwood: large standing deadwood (trees and snags) providing large hollows and spongy bark of oak, holly and willow.

55 • Deadwood target >30m3 per ha.

• Leave dead limbs in situ and artificially increase deadwood through ring barking. Consider accelerating this by wounding (routing) younger trees or inoculating trees with decay-forming fungi (formation of tree cavities in oak naturally takes more than 200 years).

• Set aside some areas of minimal intervention to allow a natural build-up of deadwood.

Important related species include hawfinch and hazel gloves fungus.

Woodland edge/scrub: border between wooded and open habitats providing shelter or an area covered with stunted trees or shrubs. Both provide cover and shelter.

• Scrub could be cut or coppiced on a staggered rotation of 8–20 years to create structural diversity and a mosaic of different aged shrubs, including birch. Cut material should be left on site.

Important related species include hawfinch, wood warbler, otter and great crested newt.

Complex understorey with glades: shrubs and regenerating trees forming a layer below the woodland canopy of variable height and density and containing small openings where conditions are shaded, humid and sheltered.

• Manage as for all-sized woodland structure.

Important related species include pine marten, brown long-eared bat and soprano pipistrelle.

Tree bark (humid): shaded, sometimes mossy bark of oak, hazel, holly and rowan or wound and rain tracks of oak in humid locations (close to water, boggy woodlands or in high rainfall areas).

• Manage for all-sized structure and diverse tree composition, including hazel, holly and rowan.

• The high humidity of the niche is provided by location, site features, e.g. ravines and water courses, or local topography.

• Retain oak trees with wounded bark.

Important related species include Fuscopannaria sampaiana (lichen).

Glades: large open areas in the woodland, with a range of vegetation types and heights in a succession from bare ground, short turf, longer vegetation, shrubs and, finally, trees.

• Use cattle grazing (low intensity for c. 3 months at 0.2–0.4 animals per ha) in autumn to maintain open conditions and variable vegetation cover (e.g. prevent dense bracken growth).

Important related species include spotted flycatcher and juniper.

Rock (humid): rocks and ground vegetation in humid, shaded conditions, e.g. ravines, cliffs and stream sides and/or in high rainfall areas.

• Avoid thinning the tree canopy where it shades ravines.

• Prevent changes in water courses or site drainage.

• Avoid moving rocks.

• Hand cut dense regeneration such as rhododendron or beech.

Important related species include Wilson’s pouchwort (liverwort) and Dumortiera hirsuta (liverwort).

Bare ground: visible topsoil in a mosaic of ground vegetation and trees. Low shade levels as a result of the open nature of the canopy.

• Disturbance by machinery during thinning, etc., creates patches of bare ground.

56 • Use low-intensity cattle grazing (c. 3 months at 0.2–0.4 animals per ha) to maintain bare ground.

• Clear regeneration from some areas to prevent over-shading.

Important related species include slow worm, sword-grass (moth), velvet tooth fungus, fused tooth fungus, bitter tooth fungus and Dumortiera hirsuta (liverwort).

5.6.4 Related links

• species associated with mature upland oak woodland

• habitat management for amphibians

• habitat management for reptiles

• managing woodlands and their mammals

• action for red squirrels

• Scotland’s rare tooth fungi management guide

• BSBI species accounts – juniper

• managing uplands for juniper

• habitats and rare, priority, protected species – Wilson's pouchwort

• lichens and bryophytes of Atlantic woodland in Scotland

5.7 Managing veteran and ancient upland oakwoods Veteran woodland is characterised by the presence of individual trees that have a large girth. Minimum diameters at breast height of greater than:

• birches: 50cm

• rowan and holly: 75cm

• oaks: 100cm

• sycamore and beech: 150cm

Trees will show at least three signs of the old growth and decay features below:

• major trunk cavities/progressive hollowing

• naturally forming water pools in major forks

• rot/decay holes >5cm diameter

• rot/decay sites, physical damage to trunks

• bark loss/loose bark

• large quantities of deadwood in the canopy

• sap runs

• crevices in the bark, under branches or in the root plate

• fungal fruiting bodies (e.g. from heart-rotting species)

• epiphytic plants (ferns, mosses, liverworts and lichens)

57 • high aesthetic interest (e.g. pollard or old coppice stool)

5.7.1 Management

• Retain all veteran and ancient trees. Treat each tree individually. Undertake as little remedial work as possible, e.g. only lowering crown height to reduce risk of windblow.

• If managed by pollarding in the past, reinstate with care using a process called ‘retrenchment’. Maintain open canopy around existing trees and do not allow young trees to over-shade them. However, avoid sudden changes by gradually opening up surrounding tree cover, e.g. reduce height by pollarding of the surrounding canopy or ring bark surrounding trees to decrease the shade slowly over a period of time.

5.7.2 Creation

• Identify younger trees as replacements.

• Allow some groups of trees to grow beyond commercial age, selecting oaks that occupy wind-firm sites and individuals already showing signs of ageing, such as irregular form and snapped limbs (or artificially age by wounding), and encourage open growth by thinning around them during management of mature woodlands.

• Trees growing in inaccessible corners and along stream sides should be retained indefinitely.

• Large old coppice stools can be retained by cutting above the level of the last cut. Stub trees and pollards, which usually grow on marginal and internal banks, can be maintained by periodic cutting, but only if the nearby woodland is opened up at the same time.

5.7.3 Managing niche features

Veteran and ancient upland oakwoods support a range of different niches, including those described below.

Tree bark (dry): dry, well-lit buttresses and bark fissures of oak; dry, well-lit and generally smooth bark of trunks or twigs of willow, hazel, holly and rowan.

• Avoid damage to hollow trunks or removal of limbs with bark features.

• Minimise mortality of trees retained as replacements and encourage frequent natural regeneration events to maintain continuity and diversity of tree species.

Important related species include pine marten, soprano pipistrelle, brown long-eared bat, bitter tooth fungus and Schismatomma graphidioides (lichen).

Deadwood: snags in shaded locations and deadwood inside hollow trunks of oak and holly.

• Leave all deadwood (standing and fallen) in situ.

• Prevent increase in shading of existing deadwood, e.g. by controlling rhododendron and/or beech regeneration. Pollard hollow trees to increase longevity.

• Provide a continuous supply of deadwood (target >30m3 per ha and more than 50 standing dead trees, some over 40cm in diameter).

• Consider inducing rot in some trees.

Complex understorey with glades: shrubs and regenerating trees forming a layer below the woodland canopy of variable height and density and containing small openings where conditions are shaded, humid and sheltered.

• Fence small areas to allow regeneration and shrubs to develop.

• Carry out thinning, and cut gaps in areas in-filled with regeneration consistent with management of ancient and veteran trees.

58 Important related species include soprano pipistrelle, brown long-eared bat, bitter tooth fungus and fused tooth fungus.

Tree bark (humid): shaded, sometimes mossy bark of oak, hazel, birch and willow or wounds and rain tracks of oak in humid locations (close to water or in high rainfall areas).

• Avoid diversion of watercourses or interventions that alter water levels.

• Minimise mortality of trees retained as replacements and encourage frequent natural regeneration of oak and birch.

• Don’t coppice hazel but allow natural die-back and regrowth.

Important related species include Fuscopannaria sampaiana (lichen).

Glades: large open areas in the woodland, with a range of vegetation types and heights in a succession from bare ground, short turf, longer vegetation, shrubs and, finally, trees.

• Use cattle grazing (low intensity for c. 3 months at 0.2–0.4 animals per ha), preferably in autumn, to maintain open conditions and variable vegetation cover (e.g. prevent dense bracken growth).

Important related species include juniper.

Bare ground: visible topsoil in a mosaic of ground vegetation and trees. Low shade levels due to the open nature of the canopy.

• Ensure where possible that all heavy machinery uses existing roads and tracks. Disturbance by machinery during thinning and group felling creates patches of bare ground.

• Use low-intensity cattle grazing (c. 3 months at 0.2–0.4 animals per ha) to maintain bare ground.

• Clear regeneration from some areas to prevent over-shading.

Important related species include sword-grass (moth), hazel gloves fungus and Dumortiera hirsuta (liverwort).

Rock (humid): rocks in humid, shaded conditions, e.g. ravines, cliffs and stream sides, and/or in high rainfall areas.

• Avoid thinning the tree canopy where it shades ravines.

• Prevent changes in water courses/site drainage.

• Avoid moving rocks.

• Hand cut dense regeneration, e.g. rhododendron or beech.

• Rank vegetation and herbaceous plants should be controlled by grazing (c. 3 months at 0.2–0.4 animals per ha).

5.7.4 Related links

• species associated with veteran upland oak woodland

• BSBI species accounts – juniper

• managing uplands for juniper

59 6 Wet woodland

6.1 Introduction This is woodland on wet acidic to neutral soils in a variety of situations, such as flushed slopes, wet hollows, valley floors and the edges of wetlands, rivers, streams and lochs. The commonest trees are willows, downy birch and alder.

Epiphytic bryophytes and lichens can be abundant and diverse. This habitat is widespread in Scotland, in both upland and lowland areas. Associated habitats are equally varied and include drier woodland of all priority types found in Scotland – heaths, bogs, other mires, fens, reedbeds, open water, grasslands and enclosed farmland.

6.2 Managing permanent open wet woodland Permanent open areas occur where the change in vegetation from woodland to open habitat is due to underlying site factors, such as change in soils (e.g. apparent as grassland and heaths) and water availability (e.g. bogs, fens, mires, open water and rivers). Open areas may also result from past disturbance that led to loss of vegetation cover, e.g. washout/erosion in a flood, and have remained open due to continued grazing and browsing. Wet woodlands occur on fairly rich sites (with the exception of wet birch woods) and nutrient availability, along with variability in local topography leading to changes in water levels, results in a very diverse ground flora.

6.2.1 Management

• Use low-intensity cattle grazing (c. 3 months at 0.1 animals per ha).

• Don’t plant open areas (leaving 50% of the riparian buffer zone unplanted).

• Rhododendron, giant hogweed, Japanese knotweed and snowberry should be controlled by cutting and spraying with herbicides approved for use near water.

• Don’t use fertilisers.

60 6.2.2 Managing niche features

Wet woodland with permanent open areas supports several different niches, including those described below.

Glades: open areas composed of tall herbs. Well lit, sheltered and with poor drainage.

• Use low-intensity cattle grazing (c. 3 months at 0.1 animals per ha), with low stocking density and far-ranging foraging.

• During late summer, cut up to 25% of the tall herb zone, cutting different areas each year to create a mosaic of vegetation of at least four different ages. Any cut material should be removed to prevent excess nutrients and the growth of rank weeds.

• Any deadwood should be left in situ.

Wet ground: ponds, semi-permanent water bodies and areas of poor drainage, e.g. water in wheel ruts and ditches.

• Allow water to collect and avoid cleaning ditches and ponds.

• Leave material such as harvesting debris or road material if it accumulates nearby.

• Avoid taking heavy machinery over wet soils.

• Don’t drain wet woodlands or the immediate surroundings.

• Maintain the water table, e.g. by blocking drains, if this is affected by management of nearby land or by river engineering.

Important related species include great crested newt.

6.2.3 Related links

• species associated with permanent open areas in wet woodland

• habitat management for amphibians

• habitat management for reptiles

6.3 Managing temporary open wet woodland Temporary open areas result from disturbance, e.g. coppicing, partial uprooting of trees (managed or as a result of natural disturbance) and other natural disturbance events, such as flooding, and in the context of woodland development may be short lived, e.g. it may be replaced by growth of regenerating trees or regrowth of coppice. Depending on site richness, plant species already occupying the site and sources of seed available, such open areas can develop species- rich ground vegetation and offer a seed bed for shrubs and tree regeneration.

6.3.1 Management

Rhododendron, giant hogweed, Japanese knotweed and snowberry should be controlled by cutting and spraying with herbicides approved for use near water.

6.3.2 Creation

• Coppice alder-dominated woodlands on drier sites (cut every 10–20 years and treat only 25% of the area at any one time).

• Pull over entire trees as a method of stimulating new growth.

6.3.3 Managing niche features

Wet woodland with temporary open areas supports several different niches, including those described below.

61 Glades: open areas in the woodland, composed of tall herbs. Well lit, sheltered and with poor drainage.

• Graze cattle, using low stocking density (c. 3 months at 0.1 animals per ha) and far-ranging foraging.

• Deadwood should be left in situ, as different species have different requirements for shade and moisture levels.

Bare ground: areas free from ground vegetation where there is a build-up of organic matter, e.g. leaves and twigs.

• Graze cattle, using low stocking density (c. 3 months at 0.1 animals per ha) and far-ranging foraging to control ground vegetation and maintaining overstorey trees nearby for continued supply of leaf litter.

6.3.4 Related links

• species associated with temporary open areas within wet woodland

6.4 Managing regenerating wet woodland This is woodland without an overstorey. Vegetation is composed of tree seedlings (<1m tall), saplings (trees >1m tall and with girths of up to 7cm diameter at breast height) and shrubs either naturally regenerating or regrowing from coppice stools. Shrubs are woody plants that are usually branching abundantly from the base, >1m tall and usually <5m tall, of the following species:

• eared willow

• osier

Other species, such as hawthorn, grey willow and goat willow, may display both shrub and tree forms.

6.4.1 Management

• Rhododendron, giant hogweed, Japanese knotweed and snowberry should be controlled by cutting and spraying with herbicides approved for use near water.

• Control grazing – use shelters to protect new trees against browsing.

• Reduce competition between establishing regeneration that is establishing and weeds, using spot application of herbicides on grasses (when at least 10m from rivers or 20m from lakes) or hand cut all other types of weeds.

6.4.2 Creation

Most regeneration probably occurs outside the wood rather than in gaps under the existing canopy.

• Germination is best on moist gravel beds on margins of watercourses.

• Acceptable regeneration is possible even where there are only 20–30 parent trees per ha.

• Light disturbance by intermittent shallow mounding or screefing of vegetation will assist natural regeneration in birch woods.

• Coppice alder-dominated woodlands on drier sites: cut every 10–20 years and treat only 25% of the area at any one time. Pull over entire trees as a method of stimulating new growth.

• Thin mature stands of ash and alder on drier sites to favour growth of ash trees for timber.

• In the absence of natural regeneration, species that are desirable as components of the woodland habitat can be planted.

• When planting, survival, particularly of alder, can be improved if the ground is prepared by patch scarification or mounding. Plant alder on weed-free mounds.

62 6.4.3 Managing niche features

Regenerating wet woodland supports a range of different niches, including those described below.

Rock (humid): mossy rocks in willow carr or next to water.

• Don’t remove rocks.

• Control vegetation growth by introducing low-intensity cattle grazing (c. 3 months at 0.1 animals per ha).

• Don’t drain wet woodlands or the immediate surroundings.

• Maintain water table, e.g. by blocking drains, if this is affected by management of nearby land or by river engineering.

Important related species include Norwegian specklebelly (lichen).

Tree bark (humid): sheltered, mossy trunks of hazel and willow close to water.

• Don’t coppice hazel and willow growing close to water. Encourage regeneration of new willow and hazel trees.

• Don’t drain wet woodlands or the immediate surroundings.

• Maintain the water table, e.g. by blocking drains, if this is affected by management of nearby land or by river engineering.

Important related species include Norwegian specklebelly (lichen).

Woodland edge/scrub: border between wooded and open habitats containing regenerating aspen and providing shelter.

• The edge or scrub zone should be cut or coppiced on a rotation of 8–20 years to create a mosaic of structural diversity and different aged shrubs.

• Allow aspen suckers to invade adjacent open areas.

• Leave cut material in place to create cover.

Important related species include otter and dark bordered beauty (moth).

Glades: open areas within areas of regeneration and scrub, with tall herbs. Well lit, sheltered and with poor drainage. Shade developing as a result of regeneration.

• Develop glades through cutting shrubs and regenerating trees. Use low-intensity cattle grazing (c. 3 months at 0.1 animals per ha) in autumn to prevent high levels of shade forming. Rotate areas grazed from one year to another to increase diversity and ensure that there are areas where plants can flower and set seed.

Important related species include song thrush.

6.4.4 Related links

• species associated with regenerating wet woodlands

• habitats and rare, priority, protected species – Norwegian specklebelly

• lichens and bryophytes of Atlantic woodland in Scotland

6.5 Managing thickets in wet woodland Most wet woods are even-aged, originating from a single event that permitted natural regeneration (e.g. a change of land use), or they were cut and allowed to regenerate without any attempt at systematic silviculture. Trees and shrubs fill the area and compete, ground flora is shaded out and no other plants colonise. Some canopy trees and understorey shrubs

63 die as a result of competition. Trees and shrubs have not yet started bearing seed/fruit (immature). The trees have a diameter at breast height of >7cm and less than 20–30cm and are usually above 5m in height.

6.5.1 Management

It is difficult to perpetuate stands at thicket or pole stage.

6.5.2 Creation

Composition and stand density will be influenced by how the woodland was established and any management applied in previous rotations, such as browsing control on regeneration forming stands and the choice of species planted during restocking.

6.5.3 Managing niche features

Wet woodland with thickets supports several different niches, including those described below.

Bare ground: wet, nutrient-poor shaded sites on seepages over sandstone rocks, sides of peat cuttings, grassy stream banks and bases of trees in carr woodland.

• Don’t cut canopy cover.

• Avoid changes in site drainage: don’t add new drainage ditches or block existing ones.

Rock (humid): mossy, wet rocks in willow carr and hazelwoods, flushes, ravines or next to water. Sheltered with dense shade from tree canopy.

• Don’t remove rocks or cut canopy cover.

• Don’t drain wet woodlands or the immediate surroundings.

• Water tables may have to be maintained, e.g. by blocking drains, if affected by management of nearby land or by river engineering.

Important related species include Norwegian specklebelly (lichen).

Tree bark (humid): on moist, shaded, sheltered smooth bark of hazel and willow near water, or in willow carrs and stands.

• Don’t cut canopy cover.

• Don’t drain wet woodlands or the immediate surroundings.

• Water tables may have to be maintained, e.g. by blocking drains, if affected by management of nearby land or by river engineering.

Important related species include Norwegian specklebelly (lichen).

6.5.4 Related links

• species associated with thickets in wet woodland

• habitats and rare, priority, protected species – Norwegian specklebelly

• lichens and bryophytes of Atlantic woodland in Scotland

6.6 Managing mature wet woodland Mature woodland is characterised by trees producing seed/fruit. The crown/canopy is usually spreading and at its maximum development. There may be canopy die-back of up to 10% as a result of competition for light and/or wind/snow damage.

64 The ground flora is developed and shrubs and regenerating trees appear on the woodland floor. All trees are >5m tall and diameters of trunks at breast height are in the range listed below:

• birches: 20–50cm

• aspen: 20–50cm

• rowan: 20–75cm

• cherry: 20–75cm

• alder: 20–80cm

• ash: 20–100cm

6.6.1 Management

• Maintain indefinitely as ‘all-sized’ structure (old growth) through active management of alder-dominated woodlands by selective thinning to favour ash trees.

• Any timber extraction should be carried out with great care, as wet soils are very susceptible to damage. In other wet woodland types, all-sized structure could be maintained through natural processes.

6.6.2 Creation

Most wet woodlands originate from natural regeneration and the species composition depends on the factors operating at the time (seed sources available, which species were favoured by available regeneration conditions, etc.). The structure of the woodland will be influenced by natural disturbance events or by historical management and levels of browsing.

More recent management to encourage natural regeneration, such as screefing in wet birch woods, selective thinning for timber production, coppicing to reinvigorate tree growth and enrichment planting during the regeneration stage, will also influence species composition and structure of the mature stand.

6.6.3 Managing niche features

Mature wet woodland supports a range of different niches, including those described below.

Bare ground: visible topsoil in a mosaic of ground vegetation and trees; organic matter built up in some places. Low levels of shade and sheltered.

• Where woodland is managed, light and frequent thinning will create suitable bare ground.

• Maintain by either mowing twice yearly or using low-intensity cattle grazing (c. 3 months at 0.1 animals per ha) in autumn, or by clearing regeneration from some areas to prevent over-shading.

• To avoid erosion of bare ground/organic-rich areas, don’t divert water courses.

Important related species include northern yellow splinter (cranefly) and Scottish yellow splinter (cranefly).

Tree bark (dry): trees with flaking bark; dry bark crevices of ash near water, well lit.

• Where woodland is managed, retain trees with rough, damaged and flaking bark in groups (i.e. don’t halo thin).

Important related species include spotted flycatcher, soprano pipistrelle, brown long-eared bat and noctule.

Deadwood: standing and fallen deadwood; large logs and snags (diameters >30cm); high stumps; decaying sapwood under bark.

• Retain all deadwood in situ.

• Deadwood can be created from windthrow and other natural processes, by injuring and ring barking mature trees (diameters >30cm) or by removing crowns and creating high stumps.

65 • Deadwood target >30m3 per ha.

Important related species include willow tit.

Glades: open areas in the woodland, composed of tall herbs. Well lit, sheltered and with poor drainage.

• Extensive, low-intensity cattle grazing (c. 3 months at 0.1 animals per ha) to maintain open areas can be beneficial to some species.

• Don’t alter water levels.

Important related species include spotted flycatcher.

Complex understorey with glades: shrubs and regenerating trees forming a layer below the woodland canopy of variable height and density and containing small openings where conditions are sheltered.

• Manage as for all-sized woodland structure as described in management of mature structural stage.

Important related species include soprano pipistrelle and brown long-eared bat.

Wet ground: ponds, semi-permanent water bodies and areas of poor drainage, e.g. water in wheel ruts and ditches.

• Allow water to collect and avoid draining wet areas or cleaning ditches and ponds.

• Leave material such as harvesting debris or road material if it accumulates nearby.

• Wheel ruts from machinery can create areas of standing water but take care not to create drainage channels.

• Don’t drain wet woodlands or the immediate surroundings.

• Water tables may have to be maintained, e.g. by blocking drains, if affected by management of adjacent land or by river engineering.

Important related species include noctule and great crested newt.

Woodland edge/scrub: border between wooded and open habitats providing cover and shelter or areas covered with stunted trees or shrubs.

• Scrub surrounding the open area should be cut or coppiced on a rotation of 8–20 years to create a mosaic of structural diversity and different aged shrubs.

Important related species include willow tit, otter and great crested newt.

6.6.4 Related links

• species associated with mature wet woodland

• habitat management for amphibians

• habitat management for reptiles

6.7 Managing veteran wet woodland Veteran woodland is characterised by the presence of individual trees that have a large girth. Minimum diameters at breast height of greater than:

• birches, hawthorn, rowan, holly, cherry, goat willow, grey willow and hazel: 50cm

• alder: 80cm

• ash: 100cm

• poplars and other willows: 150cm

66 They also show at least three of the following signs of old growth and decay:

• major trunk cavities/progressive hollowing

• naturally forming water pools in major forks

• rot/decay holes >5cm diameter

• rot/decay sites, physical damage to trunks

• bark loss/loose bark

• large quantities of deadwood in the canopy

• sap runs

• crevices in the bark, under branches or in the root plate

• fungal fruiting bodies (e.g. from heart-rotting species)

• epiphytic plants (ferns, mosses, liverworts and lichens)

• high aesthetic interest (e.g. pollard or old coppice stool)

6.7.1 Management

Retain all veteran and ancient trees. Treat each tree individually and do as little remedial work as possible.

• Willows growing in small groups and beside watercourses have often been pollarded in the past. Preserve these groups and re-initiate pollarding if appropriate.

• Maintain open canopy around existing trees and don’t allow young trees to over-shade them. However, avoid sudden changes around veteran and ancient trees, gradually opening up surrounding tree cover. For example, pollard surrounding trees to reduce the height of the surrounding canopy, or ring bark (or other equivalent methods) surrounding trees to decrease the shade slowly over a period.

6.7.2 Creation

• Identify younger trees as replacements.

• Favour development of future veterans by identifying individuals already showing signs of ageing, such as irregular form and snapped limbs (or artificially age by wounding), and encourage open growth of these by thinning around them.

6.7.3 Managing niche features

Veteran wet woodland supports a range of different niches, including those described below.

Bare ground: visible topsoil in a mosaic of ground vegetation and trees; organic matter built up in some places. Low shade and sheltered.

• Where woodland is managed, light and frequent thinning will create suitable bare ground.

• Maintain by either mowing twice yearly or using low-intensity cattle grazing (c. 3 months at 0.1 animals per ha) in autumn, clearing regeneration from some areas to prevent over-shading.

• To avoid erosion of bare ground and organic-rich areas, don’t divert water courses.

Important related species include Scottish yellow splinter (cranefly).

Tree bark (dry): trees with flaking bark; dry bark crevices of ash near water, well lit.

67 • Retain all deadwood in situ.

• Deadwood may be created from windthrow or by management described for veteran and ancient structural stage.

• Also consider removing crowns and creating high stumps from younger (mature) trees in the stand.

• Deadwood target >30m3 per ha.

Important related species include willow tit and aspen hoverfly.

Deadwood: standing and fallen deadwood; large logs and snags (diameters >30cm); high stumps; decaying sapwood under bark.

• Retain all deadwood in situ.

• Deadwood may be created from windthrow or by management described for veteran and ancient structural stage.

• Also consider removing crowns and creating high stumps from younger (mature) trees in stand.

• Deadwood target >30m3 per ha.

Important related species include willow tit and aspen hoverfly.

Woodland edge/scrub: border between wooded and open habitats providing cover and shelter or areas covered with stunted trees or shrubs.

• Scrub surrounding the open area should be cut or coppiced on a rotation of 8–20 years to create a mosaic of structural diversity and different aged shrubs. Implement this in a way that is consistent with management described for veteran and ancient structural stage.

Important related species include willow tit.

Complex understorey with glades: shrubs and regenerating trees forming a layer below the woodland canopy of variable height and density and containing small openings where conditions are sheltered.

• Carry out thinning and cut gaps in areas in-filled with regeneration consistent with management described for veteran and ancient structural stage.

Important related species include soprano pipistrelle and brown long-eared bat.

Glades: open areas in the woodland, composed of tall herbs. Well lit, sheltered and with poor drainage.

• Extensive, low-intensity cattle grazing (c. 3 months at 0.1 animals per ha) to maintain open areas can be beneficial to some species.

• Don’t alter water levels.

Important related species include spotted flycatcher.

6.7.4 Related links

• species associated with veteran wet woodland

68 7 Wood pasture and parkland

7.1 Introduction Mature, open grown trees are scattered among more open areas of grassland, bracken, heath or wetland. Younger trees may also be present and can be locally quite dense, but the total canopy cover through the area as a whole is more open than in woodland.

The trees are most commonly oak, ash, alder or birch, but can also be pine, hazel or hawthorn. The form of the older trees, which can include over-mature veterans with widely spreading branches, is typical of tree growth in open situations. Denser patches of younger trees may show the more upright growth forms found commonly in woodland. Some older trees may also show signs of traditional silvicultural management, such as pollarding.

Wood pasture and parkland is defined by the structure of the habitat: open grown trees of varying ages and sizes, including mature, over-mature or veteran specimens, are distributed irregularly forming mosaics with open habitats, such as unintensively managed grassland that is or has been grazed.

7.2 Managing permanent open wood pasture and parkland The pasture vegetation depends on the site and on previous management. In the lowlands, ancient wood pastures now encompass improved and unimproved pasture, neutral grasslands and mown amenity land. On wetter sites, the ground may be rushes or wet grassland. In the uplands, the rough grazing ranges from patches of richer calcareous grasslands to predominantly acid grasslands and heath.

7.2.1 Management

• The type of stock and stocking density needs to be chosen in accordance with the productivity of the pasture type.

69 • Grazing levels should be adjusted so that a diversity of sward heights, including occasional patches of bare ground and areas of tussocky grass, are created. Signs of overgrazing are poached and eroded ground. Insufficient grazing is indicated by pasture becoming rank and tall and dominated by coarser grasses.

• Control noxious weeds (such as Japanese knotweed) with the minimum amount of herbicide necessary applied as spot treatment or weed wipe.

• Some natural regeneration can be allowed to develop. Avoid regular mechanical cutting of ground vegetation, as this often results in impoverishment and a grassy mat.

7.2.2 Creation

• To return improved pasture to a more natural state, gradually deplete nutrients through grazing and cutting grass for silage and hay.

• Reseeding with seed collected from local grassland communities will reinforce the natural re-colonisation of native plants.

7.2.3 Managing niche features

Wood pasture and parkland with permanent open areas supports a range of different niches, including those described below.

Bare ground: visible topsoil in a mosaic of ground vegetation. Low shade and sheltered.

• Maintain by managing grazing (c. 0.5 animals per ha all year, but adjusted as above).

• Deer, rabbits and hares should be maintained at low levels, as they can contribute to creating bare ground, but individual tree protection may be needed elsewhere on the site to avoid the damaging browsing of deer and rabbits.

Important related species include tooth fungi.

Tree bark (dry): bark rough or smooth, on well-lit and sheltered trunks and branches of a variety of species (ash, elm, sycamore, oak and aspen), or on the edge of open areas.

• Use selective thinning or planting, weeding and protection (particularly from grey squirrel where present) to maintain ash, elm, sycamore, oak and aspen trees in the stand next to open ground. Avoid damage to or removal of trees in such situations.

• Manage for open ground conditions (as above).

Important related species include lesser squirrel-tail moss.

Glades: open areas composed of tall herbs. Well lit, sheltered and can be humid (either high precipitation or poor drainage).

• Maintain by managing grazing levels (c. 0.5 animals per ha all year, but adjusted as above).

• Control bracken by cutting and grazing, or if necessary with herbicide, and, in areas where control is not possible, build fire breaks around trees.

• Deadwood should be left in situ.

Important related species include northern hawk’s-beard and small pearl-bordered fritillary.

Rock (dry): mossy calcareous rocks in sheltered and well-lit locations.

• Don’t move rocks, but if unavoidable relocate the rock within the area and keep in the same orientation.

• Control herbaceous plants and grasses overgrowing rocks by cutting and grazing. Manage grazing (c. 0.5 animals per ha all year, but adjusted as above) or cut twice yearly.

70 • Spot applications of herbicides can be used to control highly competitive plant species.

7.2.4 Related links

• species associated with permanent open areas within wood pasture

• pearl-bordered fritillary and small pearl-bordered fritillary

• Identification of pearl-bordered fritillary and small pearl-bordered fritillary

7.3 Managing regenerating wood pasture and parkland This is woodland that is characterised by tree seedlings (<1m tall), saplings (trees >1m tall and with girths of up to 7cm diameter at breast height) and shrubs. Shrubs are woody plants usually branching abundantly from the base, >1m tall and usually <5m tall, of the following species:

• juniper

• blackthorn

• bramble

• dog rose

• eared willow

• dwarf birch

• gorse

• guelder rose

• broom

Other species, such as hawthorn, grey willow, hazel, holly, elder and rowan, may display both shrub and tree forms.

7.3.1 Management

• Protect all planted trees from browsing and grazing.

• Protect natural regeneration from grazing and browsing.

7.3.2 Creation

• Plant very low numbers of trees (1–50 per ha) and no shrubs.

• Where old alder, yew, aspen and hazel trees are present, relax grazing to allow regeneration from root suckers.

• Through natural processes, for old trees that have fallen over but remain partially rooted, regrow by producing new roots where trunks or branches are in contact with the ground.

7.3.3 Managing niche features

Regenerating wood pasture and parkland support several different niches, including those described below.

Woodland edge/scrub: border between wooded and open habitats or an area covered with stunted trees or shrubs. Both provide cover and shelter.

• Coppice scrub on a 3–20 year rotation. On the appropriate site type this encourages dense growth of blackthorn and hawthorn, beneficial for many species.

71 • Where rank grass dominates, this can be cut and raked off.

Important related species include dunnock, bullfinch, pearl-bordered fritillary and small pearl-bordered fritillary.

Glades: open areas with a range of vegetation types and heights including very early successional stages, bare ground and short turf, and there should be a succession of short sward moving to longer vegetation, shrubs and, finally, trees.

• Develop glades through coppicing shrubs and regenerating trees.

• In the absence of grazing, mow the centre of the glade annually in patches (in July/August). Cut up to 25% of the tall herb zone on richer, non-Molinia sites, on rotation each year, to create a mosaic of tall herbs of at least four different ages. Remove cuttings to prevent excess nutrients and the growth of rank weeds.

Important related species include song thrush.

7.3.4 Related links

• species associated with regenerating wood pasture

• pearl-bordered fritillary and small pearl-bordered fritillary

• Identification of pearl-bordered fritillary and small pearl-bordered fritillary

7.4 Managing mature wood pasture and parkland Mature woodland is characterised by trees producing seed/fruit. The crown/canopy is usually spreading and at its maximum development. There may be canopy die-back of up to 10% as a result of competition for light and/or wind/snow damage. All trees are greater than 5m tall and diameters of trunks at breast height are in the range listed below.

• birches: 20–50cm

• aspen: 20–50cm

• rowan: 20–75cm

• cherry: 20–75cm

• alder: 20–80cm

• Scots pine: 35–80cm

• oaks: 30–100cm

• ash: 20–100cm

• elm: 30–150cm

• sycamore: 20–150cm

• beech: 30–150cm

7.4.1 Management

Manage to create trees with old-growth features to replace the existing veteran and ancient trees.

7.4.2 Creation

• Structure and species composition results from site management and the natural regeneration events and tree planting that has occurred in previous decades.

72 • Denser patches of regeneration should be thinned out to a few selected trees.

• Stocking rates are usually low (1–50 trees per ha).

7.4.3 Managing niche features

Mature wood pasture and parkland support a range of different niches, including those described below.

Wet ground: rivers, streams, ponds, semi-permanent water bodies and areas of poor drainage (and/or in high rainfall areas); low shade levels and sheltered.

• Allow water to collect and avoid draining wet areas or cleaning ditches and ponds.

• Drainage of the woodland is not recommended.

Important related species include noctule, sword-grass (moth) and common blue butterfly.

Bare ground: visible topsoil in a mosaic of ground vegetation and trees. Occasional small and localised areas where soil is enriched with organic matter, e.g. leaf litter or animal dung. Low shade levels and sheltered.

• Grazing levels should be adjusted so occasional patches of bare ground are created.

• Use grazing for dunging of the site (not artificial fertilisers).

• Allow organic matter, such as leaves, to accumulate by maintaining some canopy cover.

• Deer, rabbits and hares should be maintained at low levels, as they can contribute to creating bare ground, but individual tree protection may be needed elsewhere on the site to avoid the damaging browsing of deer and rabbits.

Important related species include mealy tooth fungus, fused tooth fungus, zoned tooth fungus (Hydnellum concrescens), velvet tooth fungus, bitter tooth fungus and black tooth fungus.

Tree bark (dry): bark of a variety of species (mainly ash, elm, oak, sycamore and aspen), flaking, rough or smooth, or with wound tracks; shaded or well lit, but all in generally dry and sheltered locations.

• Carry out selective thinning to enhance or planting to maintain a mix of native trees, including oak, ash and wych elm.

• Avoid damage or removal of limbs with bark features such as crevices, wounds and rain tracks – don’t fell such trees.

Important related species include spotted flycatcher, noctule, soprano pipistrelle, brown long-eared bat, grey tooth fungus, scaly tooth fungus, Anaptychia ciliaris subsp. ciliaris (lichen), Bacidia incompta (lichen), Caloplaca luteoalba (lichen), lesser squirrel-tail moss, blunt-leaved bristle moss, dwarf bristle-moss and Schismatomma graphidioides (lichen).

Deadwood: large fallen and standing deadwood (trees and snags; diameters >30cm) providing, cavities, hollows and high and low stumps (variety of species but including Scots pine, oak, ash, elm and willow).

• Fallen and standing deadwood of all ages should be left in situ.

• A minimum of at least three standing and three fallen pieces of deadwood or at least a volume of 5m3 per ha should be maintained.

• Identify trees of suitable species that will be allowed to overmature for deadwood provision, creating more mature woodland habitat.

• Artificially increase deadwood, e.g. by strapping fallen deadwood from veterans to younger trees.

Important related species include hawfinch and pine hoverfly.

73 Woodland edge/scrub: border between wooded and open habitats or areas covered with stunted trees or shrubs. Both provide cover and shelter.

• Scrub can be coppiced on a 3–20 year rotation. On the appropriate site type this encourages dense growth of blackthorn and hawthorn, which are beneficial for many species.

• Where rank grass dominates, this can be cut and raked off.

Important related species include dingy skipper (butterfly).

Complex understorey with glades: shrubs and regenerating trees forming a layer below the woodland canopy of variable height and density and containing small openings where conditions are sheltered.

• Fence small areas to allow regeneration and shrubs to develop in the presence of continued grazing.

• Plant native shade-tolerant species if regeneration fails.

• Thin and cut gaps in areas in-filled with regeneration.

Important related species include soprano pipistrelle and brown long-eared bat.

Tree bark (humid): bark of oak, ash, elm and hazel in sheltered, humid conditions (close to water/high rainfall areas); also seepage tracks and rain tracks of bark of old trees (elm, ash, sycamore, holly and beech).

• Avoid damage or removal of limbs with bark features such as crevices, wounds and rain tracks – don’t fell such trees.

• Carry out selective thinning to enhance or planting to maintain the mix of native trees, including oak, ash and wych elm. Retain trees with wounded bark during thinning operations.

• Don’t alter the drainage of woodland.

Important related species include Fuscopannaria sampaiana (lichen).

Glades: open areas, with a range of vegetation types and heights in a succession from bare ground, short turf, longer vegetation, shrubs and, finally, trees.

• Develop glades through coppicing shrubs and regenerating trees.

• In the absence of grazing, mow the centre of the glade annually in patches.

• Cut (in July/August) up to 25% of the tall herb zone on richer, non-Molinia sites, on rotation each year, to create a mosaic of tall herbs of at least four different ages.

• Remove cuttings to prevent excess nutrients and the growth of rank weeds.

Important related species include hawfinch and spotted flycatcher.

Rock (dry): dry, shaded boulders and mossy calcareous rocks in sheltered locations.

• Don’t move rocks, but if unavoidable relocate the rock within the area and keep in the same orientation.

• Control herbaceous plants and grasses overgrowing rocks by cutting and grazing.

• Manage grazing (c. 0.5 animals per ha all year, but adjust to site) or cutting twice yearly.

• If necessary, spot applications of herbicides can be used to control highly competitive plant species.

Rock (humid): rocks (calcareous and mossy) and ground vegetation in humid, shaded conditions, e.g. ravines and stream sides, and/or in high rainfall areas.

• Don’t move rocks, or if rocks have to be moved relocate them within the area and keep in same orientation.

74 • Avoid thinning the tree canopy so shade levels are maintained.

7.4.4 Related links

• species associated with mature wood pasture

• Scotland’s rare tooth fungi management guide

• habitats and rare, priority, protected species – grey tooth fungus

7.5 Managing veteran wood pasture and parkland Veteran woodland is characterised by the presence of individual trees that have a large girth. Minimum diameters at breast height of greater than:

• birches: 50cm

• rowan, holly, cherry and willow: 75cm

• Scots pine and alder: 80cm

• oaks, ash and yew: 100cm

• elms, limes, sycamore, horse chestnut, poplars, beech and sweet chestnut: 150cm

Trees show at least three of the following signs of old growth and decay:

• major trunk cavities/progressive hollowing

• naturally forming water pools in major forks

• rot/decay holes >5cm diameter

• rot/decay sites, physical damage to trunks

• bark loss/loose bark

• large quantities of deadwood in the canopy

• sap runs

• crevices in the bark, under branches or in the root plate

• fungal fruiting bodies (e.g. from heart-rotting species)

• epiphytic plants (ferns, mosses, liverworts and lichens)

• high aesthetic interest (e.g. pollard or old coppice stool)

7.5.1 Management

• Retain all veteran and ancient trees. Treat each tree individually, and undertake as little remedial work as possible, e.g. only lowering crown height to reduce the risk of windblow.

• Maintain open canopy around existing trees and don’t allow young trees to over-shade them. However, avoid sudden changes by gradually opening up surrounding tree cover, e.g. reduce height by pollarding surrounding canopy or ring bark surrounding trees to decrease the shade slowly over a period of time.

• Identify younger trees as replacements for individuals already showing signs of ageing, e.g. irregular form and snapped limbs (or artificially age the tree by wounding it), and encourage open growth by thinning around them.

75 • Strapping fallen deadwood from veterans to younger trees can help inoculate them with the fungi, flora and insect species of the veterans.

7.5.2 Managing niche features

Veteran wood pasture and parkland support a range of different niches, including those described below.

Wet ground: rivers, streams, ponds, semi-permanent water bodies. Wet areas and temporary puddles can occur behind banks and in depressions, especially on heavy soils.

• Allow water to collect and avoid draining wet areas or cleaning ditches and ponds.

• Drainage of these patches is undesirable and drainage of the woodland is not recommended.

Important related species include noctule.

Bare ground: visible topsoil in a mosaic with ground vegetation and trees. Occasional small and localised areas where soil is enriched with organic matter, e.g. leaf litter or animal dung. Well lit but sheltered.

• Grazing levels should be adjusted so that occasional patches of bare ground are created.

• Use grazing for dunging of the site (not artificial fertilisers).

• Allow organic matter, such as leaves, to accumulate by maintaining some canopy cover.

• Deer, rabbits and hares should be maintained at low levels, as they can contribute to creating bare ground, but individual tree protection may be needed elsewhere on the site to avoid the damaging browsing of deer and rabbits.

Important related species include fused tooth fungus.

Tree bark (dry): rot holes, sap runs and rough and deeply fissured bark, usually dry and well lit. Typically oak, ash and elm.

• Use selective thinning or planting to maintain a mix of native trees, including oak, ash and wych elm.

• Avoid damage or removal of limbs with bark features such as crevices, wounds and rain tracks.

• Prevent over-shading of trees.

Important related species include spotted flycatcher, soprano pipistrelle, brown long-eared bat, noctule, Anaptychia ciliaris subsp. ciliaris (lichen), Bacidia incompta (lichen), lesser squirrel-tail moss and Schismatomma graphidioides (lichen).

Deadwood: large (minimum of 1m long and 25cm diameter), varied deadwood, attached or fallen, produced by tree ageing or pollarding and colonised by fungi and wood-boring insects.

• Retain all deadwood.

• Only move intact deadwood shortly after felling, for short distances and close to deadwood in a more advanced state of decay.

• The deadwood target is >20% of total stems dead or containing some decaying wood habitats and a minimum of three standing and three fallen pieces of deadwood per ha of a minimum 5m3 volume.

• Generate a deadwood supply by growing species with short rotation lengths, such as birch.

• Consider inducing rot in some trees.

• Strapping fallen deadwood from veterans to younger trees can help inoculate them with the deadwood species of the veterans.

76 Important related species include pine hoverfly.

Complex understorey with glades: woodland with understorey of varying height and density, containing large open areas. Well lit and sheltered.

• Fence small areas to allow regeneration and shrubs to develop in the presence of continued grazing.

• Carry out thinning and cutting gaps in areas in-filled with regeneration.

Important related species include soprano pipistrelle and brown long-eared bat.

Tree bark (humid): spongy wood inside hollow trees and bark, bare or sometimes mossy, typically of ash and elm in shaded, humid locations (close to water or in high rainfall areas).

• Use selective thinning or planting to maintain a mix of native trees, including oak, ash and wych elm.

• Avoid damage or removal of limbs with bark features such as crevices, wounds and rain tracks.

Important related species include Fuscopannaria sampaiana (lichen) and Leptogium cochleatum (lichen).

Glades: large open areas in woodland, with a range of vegetation types and heights in a succession from bare ground, short turf, longer vegetation, shrubs and, finally, trees.

• Develop glades through coppicing shrubs and regenerating trees.

• In the absence of grazing, mow the centre of the glade annually in patches (in July/August).

• Cut up to 25% of the tall herb zone on richer, non-Molinia sites, on rotation each year, to create a mosaic of tall herbs of at least four different ages.

• Hand weed to prevent competitive species from dominating.

• Control dense bracken growth (by cutting, or by herbicides if necessary) and, in areas where this is not possible, build fire breaks around trees.

Important related species include spotted flycatcher.

Rock (dry): limestone rock faces or boulders (sometime moss covered) in a mosaic with ground vegetation, scrub and trees. Usually well lit and sheltered.

• Don’t move rocks, but if unavoidable relocate the rock within the area and keep in the same orientation.

• Control herbaceous plants and grasses overgrowing rocks by cutting and grazing.

• Manage grazing (c. 0.5 animals per ha all year, but adjust to site) or cut twice yearly.

• If necessary, spot applications of herbicides can be used to control highly competitive plant species.

Rock (humid): mosaic of bare ground or moss-covered rocks and ground vegetation. Well lit and in areas with high rainfall or on sites with poor drainage and along water courses.

• Control regenerating trees and scrub by thinning/cutting to prevent over-shading, but maintain tree canopy cover.

• Avoid moving rocks.

• Avoid changing the drainage of the site (adding/blocking drains or changing flow of streams), as this may affect conditions locally.

7.5.3 Related links

• species associated with veteran wood pasture

77

78 8 Other non-UKBAP woodland habitat types

8.1 Introduction Analysis of the available evidence suggests that only a limited number of the UK Biodiversity Action Plan (UK BAP) species utilise Britain’s plantation forests. These results could be biased, because of the lack of species surveys that have been conducted in Britain’s plantations. However, it is probable that saproxylic and other species that require the veteran/ancient stand structures will be absent, mainly as a result of the lack of deadwood resources and structural diversity required. Comparisons between semi-natural woods and plantations indicate that many of the same stand structures and a proportion of the microhabitats are found in both types. Furthermore, surveys conducted in Europe and America have recorded many UK BAP species in plantations, when the microhabitat requirements have been catered for.

8.2 Managing coniferous woodland Permanent open: permanent open areas occur where the change in vegetation from woodland to open habitat is due to underlying site factors, such as change in soils (e.g. apparent as bracken areas), geology (e.g. hard knolls and scree slopes), water availability (e.g. mire, sedge-rich flushes and bogs) or where there is a maintained structure, such as a road or ride or downfalls for red deer in the uplands so that they can reach wintering grounds. Open areas of wet and dry heath may be maintained by management.

• Preserve open and wet areas within plantations.

• Don’t disturb or clear crags or other rocky features.

• Maintain the diversity of successional habitats – grassland (e.g. by grazing/mowing) and heathland (e.g. by periodic seasonal burning).

• Allow some natural regeneration to occur in a proportion of open areas to encourage mosaics or gradations of open ground and woodland.

79 Temporary open areas: where soils are suitable for woodland to develop but there are no trees. These are usually created by removal of the woodland canopy (clear-felled) as part of the patch clear-felling woodland management cycle. Such open habitats may be short lived, e.g. replaced by growth of planted/regenerating trees. Vegetation cover is likely to be present unless the ground has been recently disturbed, e.g. during harvesting. Temporary open areas usually contain deadwood. Sites subject to removal of woodland canopy in the past and intensive and continued grazing/browsing could be classed as temporary open areas, as they have the potential to support woodland again.

• Retain deadwood when harvesting the previous rotation to allow saproxylic species to survive in open habitat conditions.

• Maintain the diversity of successional habitats, such as scrub woodland, e.g. by periodic flailing.

Regeneration/shrub: this type of woodland does not have a developed overstorey. Seedling and/or sapling recruitment, either by natural regeneration or by planting, is widespread. Vegetation is composed of:

• tree seedlings ( <1m tall)

• saplings (2–4m tall and 6–10 years old)

• shrubs

Many conifers, e.g. Sitka spruce, can regenerate to form dense thickets. Other trees that are natural components of conifer woodlands include birches, alder, willows, rowan and holly, plus occasional oak, hazel and aspen, and there are a number of shrub species too. Shrubs are woody plants usually branching abundantly from the base, >1m tall and usually <5m tall, of the following species:

• juniper

• eared willow

Other species, such as rowan, may display both shrub and tree forms.

When woodland is established by planting:

• Vary spaces between trees and rows to increase the structural complexity of the resulting stand.

• Plant small patches of conifers that are of different species from the main stand.

• Increase the biodiversity potential of conifer plantations through planting a proportion of broadleaved trees, particularly small-seeded species, e.g. willow, aspen, birch and rowan.

• Structural diversity can also be incorporated by varying the density of trees achieved through selective respacing.

• Target density can range from 2,500 to 1,750 trees per ha, depending on the site conditions.

• Woodland establishment by natural regeneration can occur in the presence of light to moderate levels of grazing. Moderate and sporadic grazing is most likely to produce bursts of regeneration, which will increase the diversity of plantations.

Pole stage/thicket (closed canopy): conifers naturally develop in even-sized stands. Tree canopies fill the available space and compete directly with each other. Ground flora is shaded out and very few plants colonise. Some canopy trees and understorey shrubs die as a result of competition. Neighbouring trees fill gaps through canopy expansion. Tree density is high (>1,000 per ha), crop height is 10–20m and age is 20–30 years. Trees and shrubs have not begun bearing seed/fruit (immature). There is an accumulation of small-diameter standing deadwood.

• Extend the period of time between thinning interventions to reduce disturbance levels.

• Encourage some structural and species diversity in the stand by increasing spacing between trees. This will enhance light levels and the diversity of the understorey and may allow natural regeneration to occur.

80 • Avoid creating gaps in the canopy of much more than 4m in diameter. Thin one small block at a time.

• Thin to reduce the density of ride and woodland edge trees and to encourage the natural regeneration of native shrubs and plants and produce a graded edge structure.

Mature: trees produce seed, and growth of canopy trees has begun to significantly slow down. Mortality of individuals no longer stimulates canopy expansion of neighbouring trees. The crown/canopy usually spreads and is at its maximum development. There may be canopy die-back of up to 10% as a result of competition for light and/or wind/snow damage. All trees are 20–25m tall and 50–80 years old. Some ground flora is developed and some shrubs and regenerating trees may appear on the woodland floor.

• Encourage some structural and species diversity within the stand by felling a proportion (less than 50%) of conifer trees during the plantation cycle. This will increase light levels and may increase regeneration of the shrub layer, also encouraging development of suppressed broadleaved species and diversity of ground vegetation.

• Extend the stand age beyond commercial maturity and retain a proportion of trees (more than 10%) that will be allowed to become veterans, preferably creating patches of ‘old-growth’ forest of 0.25–2ha in size. Consider using an alternative silvicultural system to patch clear-felling, e.g. continuous cover forestry or shelterwood to maintain a continuity of canopy cover.

• Retain snags, windblown trees and fallen deadwood when felling part of the stand or when clear-felling.

• Create or maintain deadwood by leaving large-bole sections during harvesting, by ring barking standing trees or removing the crowns of conifer species. Partial damage of trees is beneficial, as these deadwood habitats then persist for longer periods than when the whole tree is killed. Aim for 20–40m3 per ha of deadwood in conifer forest in a range of decay classes and dimensions, ideally with >5m3 per ha of deadwood with diameters of more than 20cm. Leave deadwood in humid conditions close to existing stands and close to watercourses.

• Including some areas (at least 1% of total plantation) of long-term retention with minimal management increases biodiversity. For maximum benefit, patches should be between 50ha and 100ha and no further than 2km from existing semi-natural woodland. Old-growth characteristics develop 80–100 years after planting in spruce forests.

• Restructure even-aged plantation forest to create coupes of different species and at different stand development stages, e.g. less than one-third of the forest younger than pole stage, one-third pole stage to mature and one- third older than this (including long-term retentions). Species choice will be governed by site conditions, but it should be varied throughout a plantation.

8.3 Managing broadleaved woodland (non-UKBAP habitat types) Permanent open: this type of woodland occurs where a change in vegetation from woodland to open habitat is due to site factors, such as change in soils (e.g. areas used as pasture or arable land), geology (e.g. rocky outcrops), water availability (e.g. ponds, fens and rivers) or where there is a maintained structure, such as a road or ride. Woodland rides often support many of the herbs that are historically characteristic of pastures, meadows and mires in the surrounding farmland. Ride margins contain shrubs and small trees, such as dogwood, willow and hazel.

• When establishing new woodlands, buffer unplantable areas with more open space. Leave half of the riparian buffer zone unplanted.

• New rides should be a minimum of 10m wide and rides running east–west should be, at minimum, 1.5 times wider than the predicted tree height on the south side (around 30m minimum).

• Any deadwood created through ride and clearing creation or maintenance should be left in situ.

• Manage internal and external woodland edges to create wide, diffuse margins and gradual transitions rather than abrupt or hard edges.

• Create small glades by small coupe felling or group selection in the mature stand.

81 • Maintain open areas by control or removal of understorey vegetation by strimming after the summer, or by light grazing with numbers and seasonality of stock selected to control vegetation but not damage the site or compact the soil. Find more information in the Forestry Commission Woodland grazing toolbox.

• Shrub cutting on a rotational basis every few years may also be necessary.

• In stands that are, and are likely to remain, essentially even-aged, diversify the age and habitat structure in particular locations, e.g. along ride sides and edges, or around veteran historical features. Aim for 5–20% permanent open space within woodlands.

Regeneration/shrub: woodlands in which an overstorey has not yet developed. Vegetation is composed of tree seedlings, saplings and shrubs. Shrubs are woody plants, usually branching abundantly from the base, of the following species:

• blackthorn

• bramble

• dog rose

• gorse

• guelder rose

• broom

Other species, such as hawthorn, hazel, holly, elder and rowan, may display both shrub and tree forms.

• Enhance the structure, encourage regeneration and rejuvenate the understorey, by thinning of the overstorey and cutting the understorey.

• When felling stands at the end of the rotation and once advanced regeneration appears, retain some patches of understorey and sub-storey trees.

• Where possible, a proportion of thinned/clear-felled material should be left in situ to provide habitat continuity for deadwood species.

• Deadwood left in key areas, such as riparian corridors and near veteran trees or ancient woodland, will provide the greatest benefit to biodiversity.

• Whenever the understorey is cut during thinning or felling operations, the risk of browsing by deer or livestock should be considered and addressed.

• If palatable understorey species are likely to suffer serious browsing, then it will be necessary to intensify deer control and/or restrict grazing by livestock.

• When establishing the stand by planting, vary the spacing across the sites to create variation in woodland structure by clumping trees.

• Avoid using fertilisers and keep the use of pesticides and herbicides to a minimum; where necessary, use spot applications of herbicides, keeping spots as small (<1m diameter) and targeted as possible.

Pole stage/thicket (closed canopy): trees and shrubs fill the area; some trees in the canopy and shrubs in the understorey die as a result of competition. Ground flora is shaded out; there is no colonisation by other plants. Trees and shrubs are too young to bear seed/fruit. Trees usually have a girth at breast height of >7cm and are above 5m tall.

• Composition and stand density are influenced by site management in previous growth stages and rotations, e.g. the level of browsing during regeneration or restocking through to the choice of species planted.

82 • When thinning in late pole stage, select some trees to remain that have irregular forms and/or snapped limbs. Retain suppressed stems, as these may be older than surrounding trees and have developed a more diverse epiphytic community.

• Minimise disturbance during thinning operations. However, some superficial and short-lived disturbance and rutting can create valuable microhabitats.

• Thinning residues (lop and top) should be left scattered or in small heaps.

• If possible, where land adjoining woodland is farmed intensively, buffer the woodland by leaving a headland within the field adjoining the wood as fallow, rough grass or scrub to reduce spray and fertiliser drift into the woodland.

Mature: trees producing seed/fruit. The crown/canopy is spreading and at maximum development. Canopy die-back (up to 10%) from competition for light and/or wind/snow damage. Ground flora of the woodland floor is developed, with regenerating trees and shrubs. All trees >5m tall and diameters at breast height are as below:

• beech: 30–150cm

• sycamore: 20–150cm

Consider the options of using continuous cover forestry systems or small coupe felling, group selection, shelterwood or single tree selection, as opposed to clear-felling, creating an uneven-aged high forest with a pattern of small groups varying in size between 0.2 and 0.5ha.

• Small, isolated woods should not generally be clear-felled, as otherwise continuity of woodland cover is lost. In larger woods (over 10ha), larger coupes are more acceptable, but here only a small proportion of the total area (no more than 10%) should generally be felled in any 5-year period.

• Retain thinned patches or avoid clear-felling around features such as wet flushes or veteran trees. Existing veteran trees should be retained and protected. Thinning around veteran trees should be selective, with progressive, gradual reduction of the surrounding canopy.

• Harvesting methods, machines and routes should be chosen to minimise disturbance during thinning operations, but some superficial disturbance and rutting that disappears within a couple of years can create valuable habitats for species.

• Lop and top should be left scattered or in small heaps. In large woodlands, aim to retain a small proportion of the area (approx. 5%) well beyond conventional ‘productive maturity’, which is subject to minimal disturbance. In smaller woods, some individual trees, and ideally clumps, should be retained into old age to provide ‘old-growth’ habitat.

• The amount of fallen deadwood should be increased at every opportunity. Small numbers of windthrow trees are best left in situ, and deadwood retained should include a variety of species and sizes.

• Deadwood should be naturally scattered through the wood, but a few low piles or concentrations can be particularly valuable.

• Deadwood should be left in large sections and not cut up, and it is generally is best left roughly where it falls.

• If possible, where land adjoining woodland is farmed intensively, buffer the woodland by leaving a headland within the field adjoining the wood, such as fallow, rough grass or scrub, to reduce spray and fertiliser drift into the woodland.

83