looking after bryophytes in scotland’s springs and … · back from the brink management series 3...

B AC K F RO M T H E B R I N K M A N AG E M E N T S E R I E S

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Looking after bryophytes in Scotland’s springs and flushes

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Looking after bryophytes in Scotland’s springs and flushes

24028_Bryophytes_ascophyllum leaflet 27/10/2009 12:18 Page 3


Plantlife Scotland

Balallan House

Allan Park

Stirling

FK8 2QG

Tel. 01786 478509

[email protected]

All photographs copyright Gordon Rothero

unless otherwise specified

Plantlife Management seriesPlantlife is the UK's leading charity working to

protect wild plants and their habitats. The charity

has 10,000 members and owns 23 nature reserves.

Plantlife works hard to conserve threatened plants

and fungi in the places where they grow.

Conservation of these species is delivered through

the charity’s Back from the Brink species recovery

programme, which is jointly funded by

Countryside Council for Wales, Natural England,

Scottish Natural Heritage, charitable trusts,

companies and individuals. Plantlife involves its

members as volunteers (Flora Guardians) in

delivering many aspects of this work. Plantlife’s

head office is in Salisbury and the charity has

national offices in Wales and Scotland. HRH The

Prince of Wales is our Patron.

A winter view of an extensive area of flushes on the Argyll coast which have a good population of the

very rare Marsh Flapwort (Jamesoniella undulifolia)

24028_Bryophytes_ascophyllum leaflet 27/10/2009 12:18

Who is this leaflet for?This leaflet will help land managers andconservationists who manage habitats that containsprings and flushes. It describes some commonmosses and liverworts (collectively known asbryophytes) that you might find, as well as somerare and protected species and outlines theecology and threats to these species.Recommendations are given for land managementto benefit these beautiful little plants.

Why are springs and flushes important?Springs and flushes are extremely important formosses and liverworts. These small plants oftenform a significant proportion of the groundcover in this habitat. A splash of bright colour -reds, yellows and greens - and the sound oftrickling water often announces the appearanceof a flush to enliven the often rather uniformvegetation on many Scottish hills.


Springs and flushes can be dominated by just asmall number of common bryophytes or theymay be home to a diverse flora including anumber of scarce species. 41 bryophytespecies of conservation concern haveimportant populations in springs and flushesand some of these plants are confined to thishabitat. Of this list:

● ten are UK Biodiversity Action Plan species● eight are considered Vulnerable or

Endangered in the Bryophyte Red Data Book● four are on Schedule 8 of the Wildlife and

Countryside Act● one is included in a list of the world’s most

threatened bryophytes● one is listed in the Bern Convention and

on Annex IIb of the EU Habitats andSpecies Directive.

A narrow calcareous flush with a diversity of species in open heather moorland

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What are springs and flushes?Springs are usually the point source of a burn,where the water-table meets the groundsurface. A series of springs is often foundacross the slope at much the same level which,appropriately enough, is called the ‘spring line’.Springs are usually small and well-defined andoften have a complete cover of bryophyteswith just scattered flowering plants.

Flushes are areas where the flow of groundwater onto the surface is more diffuse, eitherbelow a spring or where water flows widelyover the surface of saturated ground ratherthan in a well-defined channel. Flushes can beareas of open, stony ground with only a sparseplant cover or have a complete and oftendense cover of flowering plants, usually sedgesor rushes, with the bryophytes forming aground layer under this canopy.

We tend to think of both springs and flushesas particularly associated with open habitat in


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A calcareous stony flush with the characteristic yellow-brown patches of Curled Hook-moss (Palustriella

commutata) at the top

the upland areas of Scotland but they canoccur right down to sea level and under awoodland canopy, with species compositiontending to differ markedly in each case.

The vegetation associated with the varioussprings and flushes, wherever they occur, isdetermined by the physical character of thehabitat, particularly the temperature and themineral content of the water. In terms ofnumbers of species, springs and flushes wherethe groundwater is moderately or stronglycalcareous are by far the most diverse butthe icy, nutrient-poor meltwater springs andflushes associated with areas of late-lyingsnow in the mountains are also important asthis habitat is so limited in extent. It isinteresting to note that species ofconservation concern are scattered througha variety of spring and flush types, with themost threatened bryophytes at relatively lowaltitude levels.


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Common indicator speciesThe following are common species that are goodindicators of spring and flush vegetation. WhereHooked Scorpion-moss (Scorpidium scorpioides),Yellow Starry Feather-moss (Campylium stellatum)and Curled Hook-moss (Palustriella commutata)occur together, it is a sign that the flush probablyhas a diversity of other species.

Fountain Apple-moss (Philonotis fontana) This common moss is characteristic of hillsprings and flushes where the water is not base-rich. The rather stiff, erect, bright green stemsand the often present round capsules on longstalks make it easy to recognise. It can formdense stands, covering the whole spring oroccurring in a patchwork with other bryophytes.

Marsh Forklet-moss (Dichodontium palustre) The bright mid-green colour of the patches ofthis common moss stand out from a distanceand the leaves, bent back at about half-way,give the individual shoots a star shape whenviewed from above. It often occurs withPhilonotis fontana.

Greasewort (Aneura pinguis) This is a common liverwort found in severaldifferent flush types, high in the hills, inwoodland and in dune slacks. The ‘greasy’green, strap-shaped thallus has a solid look as itis several cells thick and it can form quite largepatches or creep through other bryophytes.

Handsome Woollywort (Trichocolea

tomentella) This is a beautiful liverwort of flushed,marshy ground in woodland. The leaves aredivided into narrow segments, giving the plantits lacy appearance.

Fountain Apple-moss (Philonotis fontana)

Marsh Forklet-moss (Dichodontium palustre)

Greasewort (Aneura pinguis)

Handsome Woollywort (Trichocolea tomentella)


Yellow Starry Feather-moss(Campylium stellatum)This common species of moderately basic,stony flushes is found from lowland to hilltops.The golden shoots with sharply pointed leavesbent back from the stem give it a characteristicand easily recognised appearance.

Hooked Scorpion-moss (Scorpidium

scorpioides)In open, stony flushes on more basic ground,this is often the first moss to attract attention,its patches over the stones looking much likea mass of wriggling worms.

Curled Hook-moss (Palustriella commutata)‘Brown moss’ springs are characterised bylarge stands of Palustriella commutata orPalustriella falcata, often to the exclusion ofother bryophytes. They often occur as smallpatches at the spring-head of other calcareousflush types but in limestone areas can formextensive stands – often with some tufaformation which can be massive.

Three-ranked Spear-moss(Pseudocalliergon trifarium)Although this species is nationally scarce, itcan be frequent in the Scottish hills growingwith Scorpidium scorpioides in open stonyflushes. It is a good indicator of species-richsites where other rare species may occur. Itsnarrow, scarcely branched stems contrast withthe fat shoots of Scorpidium scorpioides, and thecharacteristic yellow-green shoot tips areeasily recognised.

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Yellow Starry Feather-moss (Campylium stellatum)

Hooked Scorpion-moss (Scorpidium scorpioides)

Curled Hook-moss (Palustriella commutata)

Three-ranked Spear-moss (Pseudocalliergon

trifarium)


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Species of conservation concern

These species are much less common, withsome being very rare indeed. They illustratethe diversity of the spring and flush habitat.

Rugged Collar-moss (Splachnum

vasculosum)A species of dung moss (Splachnaceae), thismoss has declined markedly over the years. Ithas an interesting ecology in that it isdependent on flies to transfer its sticky sporesfrom one patch of dung to another. It growson dung in at least moderately basic flushesand can persist in the same site long after thedung on which it first grew has gone.

Slender Green Feather-Moss(Hamatocaulis vernicosus) On Schedule 8 of the Wildlife and CountrysideAct and listed on the Species Directive andBerne Convention, as many of its Europeansites have been lost, this species is locallyfrequent in parts of Britain and has a numberof sites in Scotland. It occurs in moderatelybase-rich flushes, usually in sedge-richvegetation and can form extensive patches. Itis easily confused with other species,particularly Scorpidium cossonii and because ofthis has been over-recorded in the past.

Bryum schleicheri var latifolium

This large and easily recognisable moss hasalways been rare in the UK and is on Schedule8 of the Wildlife and Countryside Act. It isnow seemingly restricted to one, rathernondescript spring near Stirling. Efforts havebeen made to re-establish it in a second springhere, using material cultured from just threestems from the extant site.

Rugged Collar-moss (Splachnum vasculosum)

Bryum schleicheri var latifolium

Slender Green Feather-Moss (Hamatocaulis

vernicosus)

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Marsh Flapwort (Jamesoniella undulifolia)The one British bryophyte to grace a list of theworld’s most threatened species has apparentlybeen lost from most of its sites in Europe aswetlands have been drained. It is very rare inthe UK and is on Schedule 8 of the Wildlife andCountryside Act. In Scotland, it is restricted tothree sites, all in flushes below basic rocks onlow ground by the coast in Argyll. Its round,green leaves are rather similar to a number ofother species which grow in this habitat and soit may be overlooked.

Threats to spring and flush habitatsand the bryophytes that grow there

Climate changeA number of flush communities, particularlythose which are dependent on the cold waterassociated with areas of late snow-lie, areclearly under threat if the pattern of snowaccumulation and persistence changes. Thereis good evidence that the extent and durationof snow-lie in Scotland has diminished overthe last 25 years. Over time there may wellbe other changes as part of a complex shift inplant communities and their spatialdistribution as a result of what will probablybe a warmer and wetter climate.

PollutionThough most upland springs and flushes arewell away from the sources of pollution, thevegetation is still under threat from sulphurand nitrogen deposition which is enhanced bythe heavy rainfall and deposition in droplets ofmist when the hills are cloud-capped. Mossesand liverworts are particularly susceptible tothis kind of pollution. There is a concentrationof pollutants in the snowpack, built up over

the winter, which can then be suddenlyreleased through a rapid thaw, the so-called‘acid flush’. The long-term effects of thispollution are unclear but bryophytes have noprotective cuticle on their leaves and soabsorb water and pollutants directly into thecells. Other pollution problems are associatedwith flushes on lower ground where intensiveagriculture is taking place. Fertilising or‘dunging’ produces nitrates and phosphateswhich run off into the flushes and lead toeutrophication which is detrimental to manymosses and liverworts.

DrainageBy their nature, springs and flushes occur in wetplaces and so have always been threatened bychanges in the local hydrology. The mostobvious threat is drainage by a network ofditches in an area to improve it for grazing orthe planting of trees. The more extensiveflushes are often the main casualty of this formof management both through direct damage and

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by a prolonged drying out of the areas affected.It is quite remarkable how much of this drainagewent on in the past, possibly due to grants beingavailable, and it is not unusual to come acrosspatterns of ditches in quite remote upland areas.

This era has now passed and extensive drainagein upland areas is rare but this threat has beenreplaced by changes in hydrology that occur asa result of the construction of theinfrastructure necessary to service wind farmsand, on a smaller scale, hydro-electric schemes.All windfarms require service roads to eachturbine and these, plus the associated ditchingand drainage, will change the hydrology of theaffected area as well as having a more directlocal effect. The only Scottish site for the UKBAP liverwort Ribbonwort (Pallavicinia lyellii) isnow part of the huge Whitelees wind farm nearGlasgow. A planned wind farm in the Ochilswill affect a large population of Slender GreenFeather-Moss (Hamatocaulis vernicosus) (BernConvention, EU Directive Annex IIb, Schedule 8WCA). Apart from the flushes destroyed ormodified by the construction process, it is notclear what effects the changes in the hydrologywill have on these special plants.

ForestryIn the past, blanket afforestation and itsassociated ploughing and drainage has destroyedsprings and flushes over large areas of Scotland,particularly in the south and west. In parts ofArgyll and Dumfries and Galloway, most lowerhill slopes have at least some commercialplantations, many well into their secondrotation. The process of blanket afforestation ofopen hill land with commercial conifers hasdiminished considerably in recent years butsmall scale features like springs and flushes arestill vulnerable to forestry operations.

One, rather ironic, threat is from the otherwisecommendable zeal for the expansion ofbroadleaf and native Scots Pine woodland inScotland, where the drive to increase woodlandcover tends to overpower the consideration ofdiverse, small-scale habitats like springs andflushes. Even exclosures to encourage naturalregeneration by excluding grazing animals canbe bad for flushes as the bryophytes may beoverwhelmed by the growth of coarsevegetation or dense regeneration of trees andthe resultant leaf litter.

Trampling by livestockSprings and flushes are attractive to livestock asthey often offer localised patches of lushervegetation and a source of water during dryspells. Certain flushes can become popular andattract large numbers of animals and so be badlypoached. The damage can look dramatic but aslong as it does not persist for long periods, thebryophytes can recover and some may evenbenefit. The obvious problem lies in those siteswith a small population of a particularlyvulnerable species where the tipping point,beyond which recovery does not occur, may bedifficult to estimate. A form of poaching canalso occur with the repeated insensitive use ofall-terrain vehicles and quad-bikes in wet areas;as one part of a flush is churned up, this is thenavoided and so a large area can be damaged.



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Recommended land managementsolutions to support bryophytes of springs and flushes

Climate change and atmosphericpollutionThe problems that face flushes on the higherhills are global in nature and regrettably are notwithin the scope of the scale of management towhich we might aspire in this leaflet!

Survey and assessmentPerhaps the most important management toolfor the well-being of these diverse habitats is torecognise both their presence and their local,and sometimes national, importance. This is notalways easy to achieve; features are often smallin comparison to the area being managed andexpertise in bryophyte identification can bethinly spread. Where large-scale changes to anarea are being considered, be it for woodlandregeneration or windfarms, it is important thatany prior assessment of the site iscomprehensive enough to identify theconservation value of the bryophyte-rich springsand flushes that may occur. Contact details aregiven at the end of this leaflet for specialistsupport and advice for arranging surveys.

DrainageTo be effective, drainage has to target thoseareas where water movement can be enhancedand by definition this means that the lines offlushes will be detrimentally affected either bydrains running through them or waterchannelled into them. This means that, if anarea has to be drained, then most flushes inthat area will probably be lost or at leastradically altered. Where the drainage isdesigned to protect installations or accesstracks, it should be possible to design it with

minimum impact on important spring and flushsites by avoiding cutting through or belowflushes and avoiding having ditches and culvertsemptying into existing flushes. Again, the earlierin the design process that these springs andflushes are identified, the easier it will be to givethem some measure of protection. To informthe design process it would be useful to haveinformation on the longer term effects ofchanges in hydrology but this will only beavailable if monitoring schemes are set up.

ForestryThe best possibility of protection is input at thedesign stage so that areas of planting and anynecessary drainage can take into accountbryophyte-rich springs and flushes. It should beaccepted that, if the prime objective is to establisha woodland, then not all open flushes can bepreserved. However, if there are flushes ofconservation interest on the site some effortshould be made to limit damage caused either bydrainage or planting. Not only does this meannot planting through the flush but also meansretaining an open buffer zone of perhaps as muchas 20m around the flush so that shading and litterfall are also limited. The need for drainage mightbe avoided by selecting tree species moretolerant of waterlogging. It is probable that, asthe woodland becomes established, the nature ofthe run-off will alter and even those flushes thatare undisturbed will change in nature but may stillhave interesting bryophytes.

Pollution and poaching by livestockand deerWhere poaching is limited in both extent andduration, its effects on the flush vegetation arelikely to be moderate given that these are dynamichabitats and no management is necessary.Poaching may even be beneficial in restricting and


Contacts

Plantlife ScotlandBalallan HouseAllan ParkStirlingFK8 2QGTel 01786 [email protected]

Scottish Natural HeritageDr. David Genney, Policy & AdviceOfficer – Bryophytes, Fungi and [email protected]

British Bryological Societyc/o Gordon RotheroStronlonagGlenmassanDunoonArgyllPA23 [email protected]


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breaking up the growth of rapidly growing,carpet-forming, vascular plants like Blinks (Montiafontana) and Opposite-leaved Golden-saxifrage(Chrysosplenium oppositifolium). Where stockinglevels have been consistently high it is likely thatmost flushes will already have been altered byeutrophication by dung as well as by poaching,and may only have large stands of common,robust species. It is only where there is a springor flush with a species of conservation concernthat the level of poaching needs to be monitoredand perhaps some protection provided, e.g.temporary fencing during dry spells. Knowledgeof the site is all-important.

Damage by all-terrain vehicles and quad bikesCareful consideration of access routes forATVs and quad-bikes, favouring drier groundand avoiding springs and flushes, will limitdamage of this kind.

This leaflet was written for Plantlife Scotlandby Gordon Rothero, Bryologist

Summary of management recommendations:

● Consider the effect of drying out on springs and flushes before commencing work todig ditches.

● Identify springs and flushes on the ground where a change of land use is planned as early aspossible in the planning process.

● Surveyors (competent in recognising springs and flushes of conservation interest) shouldassess areas where a change of land use is planned and advise on further bryological surveys.

● Where drains are necessary on a site, they should not run through or below flushes; drainsand culverts should not empty into flushes.

● In woodland planting or regeneration schemes, a buffer zone of up to 20m should be leftaround springs and flushes of conservation interest.

● Avoid drainage in woodland schemes by selecting appropriate tree species.

● Access routes using all terrain vehicles and quad-bikes should avoid springs and flushes.

● High stocking densities should be avoided in areas with flushes of conservation interest.


B AC K F RO M T H E B R I N K M A N AG E M E N T S E R I E SB AC K F RO M T H E B R I N K M A N AG E M E N T S E R I E S

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www.plantlife.org.uk [email protected]

Plantlife International – The Wild Plant Conservation CharityPlantlife Scotland

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

ISBN: 978-1-907141-12-6 © October 2009

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

A bryophyte-rich flush in the Angus Hills

British Lichen Society


looking after bryophytes in scotland’s springs and … · back from the brink management series 3...

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