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Lichens and bryophytes of Atlantic woodland in Scotland:an introduction to their ecology and managementBack from the Brink Management Series

24476_AtlanticWoodland27_ascophyllum leaflet 27/04/2010 08:39 Page 3

Plantlife is the organisation that isspeaking up for the nation’s wild plants.We work hard to protect wild plants on theground and to build understanding of thevital role they play in everyone’s lives. Wildplants are essential to life – they clean ourair and water, provide food and shelter for ourinsects, birds and animals and are critical inthe fight against climate change.

Plantlife carries out practical conservationwork across Scotland, manages naturereserves, influences policy and legislation, runsevents and activities that help people discoverwild plants and works with others to promotethe conservation of wild plants for the benefitof all. HRH The Prince of Wales is our Patron.

� Lichen and bryophyte-rich oakwood © John Douglass

Wild plants have been marginalised andtaken for granted for too long. Please help us by supporting our work.

To find out more, please visit our website orcontact us at the office below.

Plantlife ScotlandBalallan HouseAllan ParkStirlingFK8 2QGTel. 01786 478509/479382

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24476_AtlanticWoodland27_ascophyllum leaflet 27/04/2010 08:39

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Atlantic woodlands –our ‘Celtic’ rainforestThe influence of the GulfStream means thatScotland’s Atlantic coasthas much milder wintersthan the east coast ofBritain and other areas ofEurope at the samelatitude. These mildwinters and ournotoriously wet weather,with abundant rainfallthroughout the year,provide ideal conditionsfor the development of adiverse flora. Within long established, semi-natural woodlands on the Atlantic coast,which are typically oakwoods, the ferns,lush carpets of bryophytes (mosses andliverworts), and colourful assemblages oflichens that develop can give thesewoodlands the character of a rainforest.This temperate or ‘Celtic’ rainforestsupports many lichen and bryophytespecies that are largely confined to thishabitat. Many of these species are absentin other parts of Britain and Europe, andsome are globally rare. Some species havetheir most significant strongholds inBritain, while others have irregulardistribution patterns with a few siteswidely scattered across the globe.Althoughthe following guidelines have beenprimarily developed for Scotland’s Atlanticoakwoods much of the information,including the managementrecommendations, applies to other types ofAtlantic woodlands throughout Scotlandand the rest of the UK.

Exposed coastal oakwood at Glenuig, Moidart © Andy Acton

Types of Atlantic woodlandsThe characteristically rich bryophyte andlichen flora of Atlantic woodlands are bestdeveloped in long established semi-naturalwoodlands, where canopy cover, including oak,has been sustained over a long period of time.However, these species can also occur inplanted oakwoods, particularly those adjacentto older Atlantic woodland. Managementrecommendations for these different types ofAtlantic woodlands are the same.

Type 1: Gnarled, often exposed, uplandoak and oak-birch woodlandThese comprise oak, oak-birch and birchwoodlands in very exposed situations and/oron very thin soils (such as over acid rockoutcrops, or on steep, often rocky terrain).These woods can be particularly importantfor oceanic bryophytes and lichens wherethey occur on slopes with a north or north-easterly aspect.


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● Manage woodlands to encourage a range oftree habitats, including dead and dyingtrees

● Ensure old and veteran trees are not felled toprotect trees with high lichen and/orbryophyte interest

● Leave all deadwood on site● Strictly limit coppicing, especially of hazel

stands, to ensure that the associated lichensand bryophytes remain as part of the habitat

● Conduct sensitive woodland thinning ● Minimise the impact of the felling of

commercial conifer plantations adjacent tovaluable lichen and bryophyte habitats

● Avoid disturbance to areas of wet or riparianwoodland

● Avoid long term exclusion of all grazing fromwoodland, using a varied level of grazing as ahabitat management tool where appropriate

● Control growth of dense thickets of treeregeneration in areas with high licheninterest

● Use small, temporary exclosures to ensurevariation in the size and age of stands ofregeneration

● Consider tree planting if diversity of treespecies is declining

● Site developments carefully to ensureminimal disturbance to mossy boulders,wayside trees, old or veteran trees, stands ofwet and riparian woodland

● Adopt the precautionary principle: if indoubt, assume that the lichen andbryophyte interest in an Atlantic woodlandwith mature and old trees and hazel stools,particularly in ravines or rocky areas, islikely to be high so such sites should bemanaged sensitively.

● Seek specialist advice and surveys prior toany operations or developments in highconservation value Atlantic woods.

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Type 2: Relatively sheltered oak-birchwoods with other tree and shrub speciesfairly frequentThese are deciduous woodlands in relativelysheltered situations such as on shelteredslopes, in wooded valleys, along shelteredcoastlines or associated with an undulatingterrain of rocky outcrops, knolls or ridgesalternating with small, damp valleys (e.g. theparallel ridges, ‘cnaps’, in Knapdale). Treespresent can include oak and birch with somerowan, hazel and willow, holly and morelocally alder and ash. Although the oak hasgenerally been subject to management in thepast, for example as pasture woodland, thewoodland has not been managed asintensively as ‘industrial’ oak wood.

Type 3: ‘Industrial’ oakwoodsThese are woods dominated by even-agedoak. The understorey is sparse and other treeand shrub species are often local (e.g. on wetground, associated with very steep ground,ravines or outcrops). Stands have beenmanaged intensively in the past for charcoal,oak bark for tanning and timber. Many are ofplantation origin. There is often clearevidence of past woodland managementsuch as charcoal hearths, stone dykes orremnants of earth banks used to excludebrowsing animals, and multi-stemmed oaksor evidence of multi-stemmed trees thathave been singled or have self singled.

Summary management recommendationsto maintain and enhance lichen andbryophyte interest● Continue woodland expansion and the

development of woodland habitat networks ● Eradicate Rhododendron ponticum from

Atlantic woodland and adjacent habitats


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Even aged Atlantic Oakwood at Elleric, Glen Creran SSSI. © Andy Acton


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Lichens of Atlantic woodlandsThere are about 1,850 lichens in Britain andover 500 of these have been recorded fromAtlantic woodlands. Our Atlantic woodlandssupport an internationally important oceaniclichen flora with a significant proportion of theEuropean and/or global populations of 86lichen species for which the UK hasinternational responsibility. Some of thesespecies are endemic. Most of these species areassociated with three important lichencommunities: the Lobarion pulmonariaecommunity (or Lobarion) on mildly acidic bark(hazel, ash, elm, rowan, willow and old oak), theParmelion laevigatae (or Parmelion) on veryacidic bark (oak, birch and alder), theGraphidion scriptae (or Graphidion), bestdeveloped on the smooth bark of hazel stemsbut also on rowan and old hollies. All threecommunities can be found in Atlanticwoodlands. See Plantlife Lichens of AtlanticWoodlands guides to find out more.

The Lobarion - the ‘lungs of the forest’This community includes some of our mostconspicuous species of epiphytic lichens;(lichens that typically grow on trees and shrubs).See Plantlife’s Lichens of Atlantic Woodlandsguide 1. One of the most characteristic anddistinctive species of this community is the TreeLungwort (Lobaria pulmonaria) which, with itssurface network of ridges, resembles green lungshanging from the trees.

Lobarion communities can include goodpopulations of a number of species that are rareelsewhere in Europe, and largely confined inBritain to ancient woodland or parkland. Welldeveloped Lobarion communities will usuallyhave a diverse range of species includingseveral Lobaria species, ‘stinky Sticta’ species

Tree lungwort (Lobaria pulmonaria) Although a fairly common lichen in Atlanticwoodland in western Scotland, this species canbe an indicator of habitat that is potentiallysuitable for other, rarer, species. It is muchmore scarce in most other parts of Britain andit is a good indicator of ancient woodland. © Andy Acton.


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(which smell fishy when wet), jelly lichens(Collema and Leptogium species), felt lichens(Degelia species), shingle lichens (Pannariaand Fuscopannaria species) and dog lichens(Peltigera species).

The Lobarion community on the even-agedoak trees of ‘industrial’ oakwoods can at firstglance appear be inconspicuous compared toother woodland types. However, some treesmay still support scarce and threatenedLobarion species and unusually goodpopulations of some other specialist lichenssuch as Nationally Scarce species SmokeyJoe (Opegrapha fumosa) and Porinacoralloidea (a crustose lichen). Individualtrees and woodland habitats pre-dating theeven-aged ‘industrial’ oakwoods are veryimportant, for example open-grown veteranpasture or boundary trees, other old treesand shrubs (e.g. hazel, rowan, birch, alder andholly) and areas that have not been plantedwith oak, such as riparian areas, very steeprocky terrain, outcrops and very wet ground.In general the more uneven the topography,and higher diversity of trees and woodlandhabitats present that predate the ‘industrial’oaks, the greater the chance that the even-aged trees will have developed or will in timedevelop a rich lichen and bryophyte flora.

The Parmelion - grey lobes and whitishcrusts on acid barkTrees with very acidic bark (birch, alder andoak) and sheltered rocks can support leafylichens with small pale greyish leafy lobes,shrubby pale greyish ‘coral’ lichens and thickwhitish crust-like ’cudbear’ lichens of theParmelion community. When well-developed,this Parmelion community can include anumber of notable lichens including scarce

A well-developed Parmelion community on oak.The presence of the community is indicated bythick whitish, porridge-like crusts (cudbearlichens) and pale grey leafy lobes. © Andy Acton.

and endemic species and is often, but notalways, indicated by an abundance of palegreyish lichens (see Plantlife’s Lichens ofAtlantic Woodland Guide 2).

The Graphidion - ‘smoothies’ on smoothhazel barkGraphidion species can be present as apatchwork of fawn, brownish, pale grey,whitish or orange patches with minute spots,pimples, warts and scribbles. Hazel inAtlantic woodlands is important because, aswell as being one of the best hosts forLobarion lichens, its smooth stems support aspecialist hyperoceanic form of theGraphidion community that is globally veryrare. Many Atlantic woodlands in westernScotland with significant stands of hazelsupport a well developed Graphidion. Hazelin Scotland is so good for lichens because ithas not been as intensively managed as inother parts of Britain (e.g. in England where itwas often coppiced on a rotational basis).


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Plagiochila punctata © Gordon Rothero

Bryophytes of Atlantic woodlandAround 50% of Scotland’s internationallyimportant oceanic bryophyte flora (about100 species) are essentially woodland plants,but the variety of habitat in rocky Atlanticoak woodlands also provides niches for awealth of other mosses and liverworts. Forexample, the oak woodland at Taynish NNRsupports 25% of the British bryophyte floraand many other woodlands are equally rich.These woodlands, particularly those withbouldery ravines, have as diverse a bryophyteflora as almost anywhere else on the planet,rivalling the tropical-montane cloud forests.

If an Atlantic woodland has a long-established cover of broadleaves, particularlyoak trees, and a variety of rocky substrates,then it will certainly have a luxuriant cover ofmosses and liverworts. Much of this carpet isof robust and common species with wefts ofLittle Shaggy-moss (Rhytidiadelphus loreus),and turfs of Greater Fork-moss (Dicranummajus) being particularly attractive. The bestindicators of an important oceanic flora arerocks and trees with cushions of theliverworts Prickly Featherwort (Plagiochilaspinulosa), Spotty Featherwort (Plagiochilapunctata) and Western Earwort (Scapaniagracilis), usually mixed with the commonSlender Mouse-tail Moss (Isotheciummyosuroides var myosuroides), and the smallWilson’s Filmy Fern (Hymenophyllumwilsonii). Prickly Featherwort, Plagiochilaspinulosa, is a European endemic specieswhich is relatively common in the west ofBritain and Ireland but it is rare elsewhere inEurope, making the large population inScotland internationally important.Communities of these species can be largeenough to completely cover big rocks and the

Plagiochila spinulosa © Gordon Rothero

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Isothecium myosuroides © Gordon Rotheroboles of substantial trees giving thesewoodlands their soft character and ‘elfinglade’ appeal.

Where these indicator species are present it islikely that other, less common species willalso occur. The best Atlantic oakwoods areoften identified by the presence of two speciesof featherwort, Western Featherwort(Plagiochila heterophylla) and DeceptiveFeatherwort (Adelanthus decipiens); bothspecies are rare in Europe and have affinitieswith the Tropics. There are also a number ofrather smaller oceanic species in thesewoodlands which are an important componentof the diversity here. Rock Fingerwort(Lepidozia cupressina), is a small liverwortwith finely divided leaves, rather like fingers,but it forms large cushions that are often

Adelanthus decipiens © Gordon Rothero

conspicuous. It seems to prefer acid rocksand trees near the coast and often occurs withTunbridge Filmy Fern (Hymenophyllumtunbrigense), and the oceanic Scott's Fork-moss (Dicranum scottianum).

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On acid-barked trees where Plagiochilaspecies are frequent there may also bepatches of the more cryptic Wedge Flapwort(Leptoscyphus cuneifolius), a nationallyscarce species locally frequent in the west ofScotland and Ireland but rare elsewhere inEurope and only known from one site inNorway. Trees and shrubs with more neutralbark may have a number of tiny oceanicliverworts as epiphytes. The most common isprobably Pearl Pouncewort (Lejeunea patens),but two other, even smaller species, PointedPouncewort (Harpalejeunea molleri), andToothed Pouncewort (Drepanolejeuneahamatifolia), can be frequent, particularly onhazel in very humid sites.

� Lepidoizia cupressina © Gordon Rothero

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� Scapania gracilis © Gordon Rothero


Identifying high conservation valueAtlantic woodland using key indicatorspecies

There are a number of lichen and bryophytespecies that, if present, can be used toindicate high conservation value Atlanticwoodland.

The presence of several of the speciesillustrated in Plantlife’s Lichens of AtlanticWoodland Guides 1 and 2 may indicate thata woodland has good Lobarion andParmelion communities. In westernScotland, particularly good indicators includeNorwegian Speckle-belly (Pseudocyphellarianorvegica,) and the Brown Shingle-lichen

� Brown Shingle Lichen (Fuscopannariasampaiana) This is another indicator of highquality lichen habitat. It is a European Red Listspecies that is considered to be Near Threatenedin Britain because of loss of suitable habitat. Itis mainly found on hazel, oak and ash in Atlanticwoodlands. It is reddish brown when dry, (palercreamy grey-brown to darker grey-brown whenwet) with pale greyish to creamy powderygranules along the lobe margins and spreadingonto the lobes. © Andy Acton.

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� The presence of Graphidion lichencommunities that look like this can indicate thepresence of high quality woodland. © AndyActon.



� Tailed Loop lichen (Hypotrachynataylorensis) – a good indicator of high qualitylichen habitat. This species has pale grey leafylobes and when well-developed the older lobesroll up to form distinctive tubes (‘tails’). © Andy Acton

� Golden Specklebelly (Pseudocyphellariacrocata) This species is also a good indicator ofhigh quality lichen habitat in western Scotland.It is a European Red List species. Mainly foundon hazel, oak, rowan and willow in Atlanticwoodlands. Lobes are pale grey brown to darkred-brown when dry (darker brown to grey brownwhen wet) with yellow powder along the marginsand powdery dots on the surface. © Andy Acton.

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(Fuscopannaria sampaiana). The presence ofbryophytes such as Prickly Featherwort(Plagiochila spinulosa), Western Earwort(Scapania gracilis) can indicate highconservation value Atlantic woodland, asdoes the presence of Wilson’s Filmy Fern(Hymenophyllum wilsonii). See Plantlife’sBryophytes of Atlantic Woodlands Guide 1.Although these species are rare in Europe,the Atlantic woodlands of Scotland support

large, internationally important communitiesof these species.

The presence of any of these indicatorspecies in an Atlantic woodland is a goodindication that the woodland may supportother important, but less conspicuous,lichens and bryophytes. Their absence,though, does not indicate the woodland is oflow interest.

Norwegian Specklebelly (Pseudocyphellaria norvegica) This species is a good indicator of highquality lichen habitat in western Scotland. It is a European Red List species that is a NationallyScarce species. It is mainly found on hazel, oak, ash and willow and occasionally rock outcrops inAtlantic woodlands. Lobes are reddish brown when dry (darker brown to grey brown when wet) withfaintly grey-lilac powder along the margins and powdery dots on the surface. © Anna Griffith.



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Important woodland featuresinfluencing the abundance anddiversity of lichens and bryophytes inAtlantic woodlands

Diverse woodland structure:The best woodlands for lichens andbryophytes often have a diverse structurethat includes areas with a closed canopy,dappled shade, glades, a patchy understoreyincluding hazel, some denser stands of hazel,standing and fallen deadwood and veterantrees. These conditions provide a range oflight/shade regimes and variation inhumidity giving a variety of niches for bothbryophytes and lichens.

Diversity of tree and shrub species and ages:Different tree and shrub species havedifferent bark characteristics, and thesecharacteristics alter as a tree matures.Saplings and very young trees are generallyof low importance for lichen and bryophyteepiphytes. While dense regeneration canpose a shade threat to notable lichens, somesaplings and young trees are desirable toprovide future habitat and add to overallbiodiversity because they provide a niche forearly-colonising species.

Old and veteran trees:These act as an important refuge for avariety of species as they often provide arange of micro-habitats. Some may be relicttrees from former pastoral systems, includingold, open-grown ancient pasture trees. Theycan also provide standing and fallendeadwood habitat. Large, old stools of hazelcan be particularly important for lichens andbryophytes. Large trees along margins of anotherwise shaded wood (boundary trees and

wayside trees) can be important for morelight-demanding species of lichen, thoughthe open habitat generally means that theseboundary and wayside trees are lessimportant for oceanic bryophytes.

Less intensively managed woodlandhabitats:Wet woods, riparian woods, valley woodlandand ravines, and woodland on steep, rockyterrain have often been less intensivelymanaged in the past and can support agreater diversity of tree and shrub species.In long established plantation oakwood, suchstands are particularly important as manytree and shrub species and their associatedlichen and bryophyte flora may be confinedto them. These stands can be an importantsource for re-colonisation as the oakwoodland matures.

Diverse topography including valleys,ravines and rock outcrops:Variation in topography results in a range ofwoodland habitats with a diversity of lightand humidity regimes that will ensure theoptimum conditions for a range of lowerplants and thus give a diverse flora. Aspectcan be important; for example well-lit, south-facing slopes will have a different flora fromshadier, north-facing slopes. Particularlyimportant topographical features in Atlanticwoodlands include river valleys and ravines,rocky outcrops, flushed slopes, flat terraces,boulders, rocky slopes and boulder screes.

Rock outcrops and boulders:These habitats are good for lichens that growon rocks and are of overwhelmingimportance for oceanic bryophytes becauseof the lack of competition by other, more


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A diverse range of tree species and steep slopes provides a range of habitats forepiphytes. D Long / Plantlife



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Plagiochila atlantica bryophyte community in woodland in Beasdale. © Gordon Rothero

robust woodland floor species. The cycle ofaccumulation of plants on the rock-faceand subsequent sloughing off provides asteady supply of new, open habitat for thesmaller species.

Threats to lichens and bryophytes inAtlantic woodland

Rhododendron ponticum:Dense Rhododendron ponticum casts a veryheavy shade that is disastrous for anyexisting lichen or bryophyte species, makingit a major threat to Atlantic lichens andbryophytes in western Scotland.

Clearfelling and rotational cutting:Large scale felling and rotational cutting,including coppice, within Atlantic woodlandswill seriously damage any lichen andbryophyte interest and should be avoided orminimised where possible. Any tree fellingand canopy loss can reduce humidity levelsand lead to direct loss of epiphytes, especiallybryophytes, but also those lichens that requiremore humid conditions such as jelly lichens.Ground disturbance may also directly threatenbryophytes, including those on boulders, andmay adversely affect hydrological regimes,thus affecting humidity. Small scale thinning or cutting are always


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Rhododendron ponticum invasion of Atlanticwoodland © Gordon Rothero

preferable to large-scale operations, althoughthere is still the risk that stems or trees withhigh lichen or bryophyte interest could beinadvertently removed. If a crop is desired,for wood fuel for example, it would be farpreferable to thin dense thickets of recentlyestablished trees (e.g. birch), rather thancoppice hazel.

Hazel is one of the most important species inAtlantic woodlands for lichens. Hazel isnaturally multi-stemmed so it should not beassumed that the presence of multi-stemmed stools indicates ex-hazel coppice.Although hazel was cut in the past, in theAtlantic woodlands of western Scotland thishas generally not been done on an intensive,rotational basis, which is why hazel stands inScottish Atlantic woodlands have suchdiverse bryophyte and lichen communities.It is a common misconception that hazelrequires coppicing; any Atlantic hazel standthat is important for lichens and bryophytesand which has been subject to past cutting isimportant despite any cutting rather thanbecause of it.

Scrub clearance:The clearance of ‘scrubby’ woods of birch,willow and hazel may be a threat to veryimportant habitats for lichens andbryophytes. Wet woods of birch and willowmay be important habitats for Parmelionlichens and epiphytic oceanic bryophytes.Hazel in western Scotland can be ofinternational importance for Lobarion andGraphidion lichens.

Long term overgrazing of woodland: Very long-term overgrazing prevents woodlandregeneration and ultimately leads to the loss

or fragmentation of woodland cover, both ofwhich are major threats to lichens andbryophytes. It can eventually lead to a declinein the diversity of tree species. For example oldtrees of palatable species with a relativelyshort life span, such as rowan, may disappear. It is important to note, however, thatwoodlands can survive relatively long periodsof heavy grazing and old pasture woodlandsare some of the best habitats for lichens.Provided the continued presence of old trees ofthe full range of tree species is assured in thelong term, some canopy loss may not be adirect threat to lichens. However, any generalopening up of the canopy, resulting in lowerhumidity levels, will be unfavourable foroceanic bryophytes unless the sites are veryrocky or have a northerly aspect.

Undergrazing or stock exclusion:The decline in low-intensity livestock farmingaccompanied by the continued decline instocking levels may lead to expansion andregeneration of our Atlantic woodlands.However, grazing levels in these woodlandsneed to be carefully managed to ensure thatregeneration of native tree species isoccurring but not developing into thickets.These can shade out important lichencommunities in the short term.


Well-intentioned woodland regenerationschemes involving the erection of stock and/ordeer fencing can be a potential threat towoodland plants, where they are left in placetoo long and allow the development of densethickets of native and non-native species(including birch, holly, sycamore, beech andsitka spruce). The infilling of glades withthickets of natural tree regeneration canthreaten a range of habitats such as species-rich grassland, flushes and mires and mayreduce available habitat for some species,including, for example, some of the Lobarionspecies on old trees and hazel in glades, alongwoodland edges or waysides. In addition thespread of ivy, and even in extreme caseshoneysuckle, when unhindered by browsingcan smother trunks of trees, rocky outcropsand boulders thereby reducing availablehabitat for lichens and bryophytes. The mainproblem for bryophytes within exclosures isthe growth of a dense herb and dwarf shrublayer which can completely cover importantcommunities on rocks and tree bases. Theseplant communities can also produce a lot oflitter which can accumulate, smothering lowrocks and changing the character of flushes.

Developments such as hydropowerschemes and road improvements:Infrastructure features such as roads andpipeline routes can lead to the direct loss oftrees or damage to woodland habitats,resulting in lower humidity levels. Inaddition, developments such as hydropowerschemes may pose other threats throughtheir impact on river hydrology. There is adirect impact on those species growing onrock in the water channel but there may alsobe changes in the humidity regime in thesurrounding woodland as flow rates arereduced over the length of river affected.

Managing woodlands for wildlife:avoiding species conflicts

Changing woodland structureManaging woodlands for bryophytes andlichens is beneficial to both groups and isbetter than no management at all. However,the two groups do require slightly differentconditions: oceanic bryophytes are moresusceptible to desiccation than manylichens and lichens are more susceptible toshading. Hence, a policy of opening upglades for the lichen interest in a woodlandmay be beneficial for lichens if it avoidsfelling trees with high lichen interest but thispractice has the potential to damage thebryophyte interest. Lichens are morethreatened by heavy shading thanbryophytes, so a policy of ‘filling in’ thecanopy to increase humidity levels forbryophytes may pose a shade threat tovaluable lichen communities. In either situation, it would be wise to assessthe lichen and bryophyte floras in order tominimise potential negative impacts. Onething is clear, very heavy shade dramatically


Removing non native tree species from nativewoodlands is one way to improve woodlandstructure for lichens and bryophytes and a rangeof other species. © D Long / Plantlife

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reduces the diversity of both lichens andbryophytes and should be avoided.

Grazing and browsing Grazing and browsing by stock and deer can befully compatible with management for lichensand bryophytes. Domestic stock or deer canbe important conservation management tools.Grazing levels can be manipulated to, forexample, expose a suitable seed bed for treeseedlings, permit and control levels of treeregeneration, determining future woodlandstructure, and to maintain woodland glades.Grazing can be used to maintain a species-richsward and, especially in the case of cattle, canbe used to control rank vegetation andmaintain a variable sward height forinvertebrates and woodland ground flora.

Other woodland flora and fauna Management of woodland for lichens andbryophytes is compatible with managementfor fungi, butterflies, other invertebrates,

bats, birds and vascular plants. Managementfor bats involves retention of veteran treesand gladed areas, including open groundalong woodland edges. These aims are fullycompatible with the lichen and bryophyteinterest. Butterflies associated withwoodland habitats are, like many well-developed lichen communities, reliant on thepresence of gladed conditions. Ensuring thatnew glades are opening up as trees die andregenerate will maintain maximum diversityof habitat niches for a wide range of wildlifeat different life stages.

Management recommendations forlichens and bryophytes of Atlanticwoodlands

Expanding and connecting areas of broadleafwoodland is the best approach for ensuring abright future for oceanic lichens andbryophytes. However, as many Atlanticlichens and bryophytes are inconspicuous,

Gaps in the canopy provide a mosaic of habitats to support other woodland species. © D Long / Plantlife



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the boundaries of existing woodlands tolink up existing fragments of old woodland.Extensive, dense tree regeneration withinthe boundary of existing woodland shouldbe avoided in areas with high lichen andbryophyte interest. In some woods, onlyrelatively low recruitment rates may benecessary for woodland continuity.

● Eradicate Rhododendron ponticum Ideally all Rhododendron ponticumshould be eradicated from Atlanticwoodland and adjacent habitats.However, in practice, sites for R. ponticummanagement often need to be prioritisedfor practical and economic reasons. Longand Williams (2007) recommend:(a) Eradicating or at least controlling the

spread of R. ponticum in highconservation value Atlantic woodland,where key bryophyte and lichencommunities are present;

(b) Identifying appropriateeradication/control techniquesdepending on site conditions andspecies present;

(c) Ensuring that adjacent habitats arefree from flowering R. ponticum,which will act as a continuous seedsource for reinvasion.

● Manage woodlands to encourage arange of tree habitatsA general principle would be to manageto ensure the continued presence of arange of tree and shrub species and ages,including dead and dying trees. This willprovide a range of micro-habitatsincluding rough and smooth bark,sheltered or exposed bark, very acidicbark (e.g. oak, birch and alder) and trees

they have frequently been neglected in thepast when decisions have been made on sitemanagement. Today, the profile of lichensand bryophytes has been raised but it is stilleasy to overlook them when it comes tomaking decisions on site management.Even when their importance on a site isrecognised, it is often assumed that if weensure continuity of large scale habitat (iethe trees), the lichens and bryopyhtes willlook after themselves. There are potentiallyserious implications of this approach: forexample the encouragement of high levels oftree regeneration leading to dense shade willthreaten lichen, bryophyte and floweringplant communities. It makes sensetherefore for management to considerspecifically the needs of lichens andbryophytes, enabling populations andcommunities to persist and thrive, whilstpotential lichen and bryophyte habitat isexpanded. Many of these recommendationswill benefit other woodland species andencourage a diversity of woodland structureand tree composition. Some generalguidelines are given below and further detailis available in Worrell et al (2010).

● Continue woodland expansion and the development of woodland habitat networks Woodland loss and fragmentation hashistorically been the major threat tolichens and bryophytes and in many areas,the fragmentation of suitable habitat isstill a threat. Woodland expansion and theestablishment of woodland habitatnetworks are important for the long termcontinuity and diversity of the lichen andbryophyte communities. Woodlandexpansion should be encouraged beyond



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and shrubs with less strongly acidic bark(e.g. ash, hazel, elm, willow and old oak).

● Retain and avoid damage to old andveteran trees Ensuring that old and veteran trees arenot felled means that trees with highlichen and/or bryophyte interest areretained as important habitat.

● Leave all deadwood on siteDeadwood, both fallen and standing, is animportant habitat for both bryophytesand lichens as well as fungi andinvertebrates.

● Strictly limit coppicing, especially ofhazel stands As a general rule, cropping of hazel inAtlantic woods should be extremelylimited. Complete coppicing of the stoolis to be avoided, as all lichens andbryophytes (specialist as well ascommon species) get taken away withthe cut product. These specialist speciesare very poor colonisers and thereforeunlikely ever to return. Very small-scaleselective cutting of individual stems canbe undertaken, for thatching spars, pea-sticks, walking sticks for example, as thisallows the overall integrity of the stool toremain fairly intact, and ensures that theassociated lichens and bryophytesremain as part of the habitat. If a manager wants to coppice birchregularly employing larger scaleoperations, perhaps for wood fuel, then itis best to plant ‘new’ stands establishedpurely for that purpose, rather thancoppicing in established Atlantic woods.This is because the resulting regular

fluctuations of light and humidity aroundestablished lichen or bryophyte-richhabitats will lead to a rapid decline inthese communities, which are unable totolerate such rapid habitat changes.

● Conduct sensitive woodland thinning Lichen assemblages on trees can generallytolerate some thinning operations.Thinning may be beneficial where densethickets of regeneration are posing a threatto established epiphyte-rich habitats.Small-scale thinning in even-aged woods,for example of Type 3 oakwoods for timber,can be used to diversify woodlandstructure, using patch thinning to createsmall glades, and thus diversify habitat.

The best areas of Atlantic oak woodlandfor oceanic bryophytes are those wherethere has been a continuity of canopycover for a long period. The level ofmanagement does not seem to be criticalas long as the solid substrates such asrocks and trees have had some bufferingfrom changes in humidity as a result ofthinning. Carrying out thinning on arotational basis is likely to be damaging,as many of the more important speciesare slow colonisers with more specifichabitat niche requirements.

● Minimise the impact of the felling ofcommercial conifer plantationsadjacent to valuable lichen andbryophyte habitatsCommercial conifer felling can lead to adramatic reduction in humidity levels inadjacent broadleaf woodland leading tothe desiccation, and potential loss, ofsome bryophytes and lichens. With


larger stands of broadleaf woodland, thisis only likely to affect the edge and istherefore unlikely to affect the lichenand bryophyte communitiessignificantly. However, the lichens andbryophytes associated with smallerstands of trees within conifer plantationsmay be more vulnerable, especially innarrow strips of riparian woodland forexample. If there are any particularlyrare and important lichen and bryophytespecies present, which is highly likely inravines, restock with a wide band ofnative broadleaf trees, a minimum of 30metres, along the ravine / feature ofinterest. Although some loss inbryophyte and lichen interest may occur,this provides future buffering for ongoingcommercial conifer harvesting.

● Avoid disturbance to areas of wet orriparian woodland Wet woodland, including areas of scrubbybirch and willow, should be leftundisturbed. Such wet, scrubby areas areoften dismissed as of low conservationinterest but may be important habitatsfor lichens and bryophytes.

● Avoid long term exclusion of grazingfrom woodlandSome level of grazing is generallydesirable but prescribing a fixed grazinglevel is not always possible. Theseasonality and the number and type ofgrazing animals, cattle, sheep or ponies,should be flexible and determined by thefluctuating condition of a site, forexample in reaction to wet summers or

23

Sympathetic plantation removal adjacent to lichen-rich native woodland, Tobermory, Mull © J Long



long dry summers. Grazing can be usedto ensure the continuity of a wide rangeof habitat niches, based on a diverse treeage structure. High grazing levels canbe sustained for long periods providedwoodland continuity is assured in thelong term. Conversely, sustained periodsof very low grazing levels can be aserious threat to the diversity ofwoodland structure, affecting, forexample, glades, flushes and species-richgrassland. Temporary low grazing levels(or temporary enclosure) can allow aflush of regeneration and ensurewoodland continuity in the long term.However, woodland regenerationexclosures should be planned astemporary measures. If left in place fortoo long they may permit undesirable

thickets of dense regeneration tobecome widespread (see below).

● Control growth of dense thickets oftree regeneration in areas with highlichen interestCattle or deer can control the formationof dense thickets if introduced earlyenough, otherwise hand cutting might benecessary before deer or other stock canhave any significant impact. Somespecies of tree and shrub and/or growthstages may be avoided by certainanimals. Different grazing animals can beused to target particular areas withproblem excessive scrub regeneration.Where trees along well lit woodland edgessupport well developed lichencommunities, extensive denseregeneration is not recommended.

● Use smaller, temporary exclosuresPatchiness is good where there is varietyin the size and age of stands ofregeneration, as well as variations inshade, light and humidity levels. Fencingto encourage tree regeneration shouldonly be seen as a temporary measure,and enclosing the whole woodland areafor a long period should be avoided.Smaller exclosures, exclosures with gatesto allow grazing animals controlled entryor ‘leaky’ fences (where stock canperiodically gain access for a limitedtime) may help to ensure a more variedwoodland structure develops. This wouldneed careful monitoring to ensure thatthe regeneration of more palatablespecies of tree and shrub is not affected,leading to a reduction in diversity of tree species.

Some grazing can help to maintain grassy glades,retaining woodland structure diversity. © D Long / Plantlife

24



● Tree plantingPlanting should be considered if thediversity of tree species is declining.Suitable ground often has birch and rowanseedlings and young saplings suppressedby browsing. However, regeneration ofdesirable species such as hazel, ash andoak may be absent as these species cantake a long time to establish naturally. Ifthis is the case, then consideration couldbe given to planting, although plantingshould only be at low densities. Until theyare established, trees could be protectedwith staked mesh. Care should be takento avoid damage to mature trees byscraping as this could easily dislodge anylichen or bryophyte interest.

● Careful siting and management ofdevelopmentsAny construction works, including accesstracks should, where possible, be sited orrouted to ensure minimal disturbance tomossy boulders, wayside trees, old orveteran trees, areas of wet woodland andriparian areas. If the felling of longestablished Atlantic woodland trees,including scrubby woodlands, cannot beavoided, specialist lichen and bryophyteadvice can help to minimise impacts.Advice from specialists should also besought on the impacts of changes inhydrology as a result of water extractionfor hydro-electric power schemes.

● Adopt the precautionary principleAtlantic woodlands are very specialhabitats and some are protected byconservation designations, but manywoodlands that are important for lichensand bryophytes lie outside designated

sites. If in doubt, it is a fairly safe toassume that the lichen and bryophyteinterest in an Atlantic woodland withmature and old trees and hazel stools islikely to be high, and particularly so if thewoodland is rocky or has a ravine. Suchsites should be managed sensitively.

● Specialist advice and surveySpecialist lichen and bryophyte advice isstrongly recommended prior to anyoperations such as thinning orinfrastructure development in or nearhigh conservation value Atlantic woods, toidentify areas suitable or unsuitable forthese operations, including marking up ofindividual trees or shrubs that should beretained. Contact details for support aregiven at the end of this leaflet.

Rocky outcrops within woodland provide amosaic of habitats for bryophytes and lichens.© D Long / Plantlife

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26

Further reading

Crawford, C. (2002) A Field Guide to CommonMosses and Liverworts of Britain and Ireland’sWoodlands 3rd Edition. The Natural ResourceConsultancy.

Rothero, G. (2010) Bryophytes of Atlanticwoodland Guides 1 and 2. Plantlife Scotland.

Dobson, F. (2005) Lichens: An Illustrated Guideto the British and Irish Species 5th Edition.Richmond Publishing Co. Ltd.

Fletcher, A. (ed.) (2001) Lichen HabitatManagement. British Lichen Society andCountryside Council for Wales.

Acton, A. & Griffith, A. (2008) Lichens of AtlanticWoodlands Guides 1 and 2. Plantlife Scotland.

Atherton, I., Bosanquet , S. & Lawley, M (2010)Mosses and liverworts of Britain and Ireland, afield guide. British Bryological Society.

Porley, R. & Hodgetts, N., (2005) New NaturalistMosses and Liverworts. Harper Collins.

Long, D. & Williams, J. (2007) Rhododendronponticum: impact on lower plants and fungicommunities on the west coast of Scotland,.Plantlife Scotland.

Worrell, R., Long, D., Rothero, G and Coppins, S.(2010) Management of woodland plants inAtlantic broadleaved woodland: a conservationframework. Plantlife Scotland.

Other sources of information

www.bls.org.uk The British Lichen Society (BLS).

www.britishbryologicalsociety.org.ukThe British Bryological Society (BBS).

www.nwdg.org.uk The Native Woodland Discussion Group(NWDG) runs regular training courses onlichens and bryophytes of Atlantic woodlands.

www.britishlichens.co.ukThe britishlichens website has useful photosof many British lichens.

Who to contact for advicePlantlife Scotland, Balallan House, Allan Park, Stirling FK8 2QGTel: +44 (0)1786 478509www.plantlife.org.uk,[email protected]

Scottish Natural Heritage, Great Glen House, Leachkin Road, Inverness,IV3 8NW.Tel. 01463 72 5000 www.snh.org.uk Dr David Genney, Policy & Advice Officer –Bryophytes, Lichens and Fungi:[email protected]

This leaflet has been written and illustrated by Plantlife

Scotland with contributions from Andy Acton

(lichenologist, [email protected]) and

Gordon Rothero (bryologist, [email protected]).

Oakwood types largely follow the guidelines developed

by Sandy Coppins for monitoring the condition of

oakwoods that have been designated Sites of Special

Scientific Interest (SSSIs) for their lichen assemblage.


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www.plantlife.org.uk [email protected]

Plantlife – speaking up for the nation’s wild plantsPlantlife Scotland

Balallan House, Allan Park, Stirling FK8 2QGTel. 01786 478509

ISBN 978-1-907141-26-3 © March 2010

Plantlife International – The Wild Plant Conservation Charity is a charitable company limited by guarantee.Registered Charity Number: 1059559 Registered Company Number: 3166339. Registered in England

Charity registered in Scotland no. SC038951

Dicranum scottianum © Gordon Rothero

British Lichen Society

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