natural england - bracken tin048 edition 1

7/30/2019 Natural England - Bracken TIN048 Edition 1

1/7

Natural England Technical Information Note TIN048

First edition 16 October 2008

www.naturalengland.org.uk

Bracken management and controlBracken Pter id ium aqui l inumis a crucial component of many habitats and supports anumber of scarce and declining animal species. It adds structure and colour to the

landscape and is a common feature of many of England's finest areas of countryside.However, it can reduce the grazing area available for livestock, prevent effectivelivestock husbandry and damage wildlife habitats and underground archaeology. Thisnote provides information on bracken management and control and strategies forvegetation recovery and aftercare. For further information on bracken see SIN011Brackenand TIN047 Bracken man agement: ecological, archaeological and landscapeissues and prior i t ies.

Management and control

Before starting a bracken management orcontrol programme it is important to identify clear

goals of what is to be achieved and whatproblems are likely to be encountered. Brackenmanagement should be considered as onecomponent of a long term programme ofvegetation management.

Effective chemical treatment can achieve up to98% kill of bracken, but programmes often faildue to poor follow up treatments or post-controlmanagement failing to achieve vegetationrecovery. Effective mechanical treatment cantake a number of years depending on the vigourof the plant and the type of control method used.

It may not be possible to achieve totaleradication, particularly on semi-natural habitatsand extensively managed areas, and long termmanagement of the population may be moreappropriate than complete control. Completecontrol may be possible on intensively managedagricultural land, but this will require a full,intensive and systemic approach.

Key factors to consider:

There is no merit in controlling dense brackenwithout considering what vegetation willreplace it.

Complete eradication is unlikely to beappropriate particularly where there is existingenvironmental interest.

The best and most cost-effective results willcome from treating stands that still possesssome ground vegetation.

Maintaining even low levels of bracken is likelyto require ongoing control treatments andsupporting grazing strategies.

The impact of bracken control on thelandscape. Avoid leaving rectangular blocksand undertaking large scale clearance at onetime. Create irregular patches with boundariesagainst natural features.

Evaluate the extent of any archaeologicalremains and the ability to effectively eradicateand maintain a bracken-free environment

around and above these remains. This mayrequire advice from an archaeologist.Appropriate control can improve the conditionand visibility of archaeological sites, butinappropriate control can damagearchaeological features.

Whether control is justified on sites with limitedagricultural potential or environmental value:natural succession or planting for woodlandmay be more appropriate.

Possible impacts on water quality. In the pastresidues of asulam have been found indrinking water bore-holes in areas that havebeen sprayed for bracken.


2/7

Page 2


Bracken management and control

Do not control bracken where:

Sites have important woodland ground flora

(eg bluebells and wood anemones) beneaththe canopy. In South West and North WestEngland, avoid sites with violets or cow-wheatbeneath the canopy as these may be importantfor fritillary butterflies.

Ferns of ecological interest are present oroccur nearby as they may be damaged bydrifting spray. Care should be taken near rockyareas and upland watercourses that harbourmany ferns.

Bracken occurs on steep slopes which may be

subject to erosion whilst without vegetation.The minimum limit suggested is 110 m on landnot under cultivation. Mechanical control underthese conditions could lead to soildisplacement, and the erosion and movementof soil or vegetation at lower elevations. Itcould also encourage erosion by waterincluding the development of gullies and rills.Chemical control of bracken on slopes canalso result in run-off downhill, and risksdamage to non-target species and pollution ofupland water courses. If possible, carry out an

erosion risk assessment.The long-term costs exceed the likely

environmental benefits.

Control may result in the damage ofarchaeological features, notably as a result ofthe chosen control methodology.

Before embarking on any form of brackencontrol inspect the site during the winter monthsto check for obstacles, hidden pits or ditches oranything else that could cause injury to theoperator, damage or an overturn.

Legislation

On Sites of Special Scientific Interest (SSSIs)consent may be required and you should consultNatural England before undertaking anymanagement.

Where the objective of control is the agriculturalintensification of uncultivated land and semi-natural areas, the 2006 Environmental ImpactAssessment Regulations, EIA apply, and

Natural England will need to approve theproposals.

The EIA regulations are reinforced under CrossCompliance, Good Agricultural and

Environmental Condition(GAEC). GAEC 5specifically relates to EIA. If bracken controlinvolves cultivation or soil management, GAEC1, which relates to soils also applies, particularlyin the uplands.

If considering the use of pesticides theEnvironment Agency should be consulted andthey may need to give their consent if there arewater courses in the vicinity. For furtherinformation see:

Application to use herbicides in or near waterwww.environment-agency.gov.uk/commondata/acrobat/wqm1_form_1797463.pdfand

accompanying guidance noteswww.environment-agency.gov.uk/commondata/acrobat/wqm1_notes201_1797478.pdf.

Burning bracken is controlled by the Heatherand Grass Etc. (Burning) (Amendment)Regulations 1987 (SI 1987 No 1208) made

under Section 20 of the Hill Farming Act 1985.

Health and safety

See appendix at the end of this leaflet.

The risks to drinking water from pesticidesused to control bracken

Residues of asulam have been found in drinkingwater bore-holes on land that has been subjectto chemical bracken control. Careful assessmentmust be given to mitigating the risks of over-

spraying and drift on water sources andabstraction points whether they are privatelyowned or owned by a water company. Forfurther advice contact your local EnvironmentAgency office or the Natural England NationalPesticides and Toxic Substances Specialist.

Methods of bracken control

Control should be considered as a stagedprocess, with at least two stages. The first istreatment to reduce the cover of bracken andopen up the stand for either natural

regeneration, re-vegetation treatments orgrazing.
http://www.environment-agency.gov.uk/commondata/acrobat/wqm1_form_1797463.pdfhttp://www.environment-agency.gov.uk/commondata/acrobat/wqm1_form_1797463.pdfhttp://www.environment-agency.gov.uk/commondata/acrobat/wqm1_form_1797463.pdfhttp://www.environment-agency.gov.uk/commondata/acrobat/wqm1_form_1797463.pdfhttp://www.environment-agency.gov.uk/commondata/acrobat/wqm1_form_1797463.pdfhttp://www.environment-agency.gov.uk/commondata/acrobat/wqm1_form_1797463.pdf


3/7

Page 3



The second stage involves the use of either:

intensive follow-up treatments aimed ateradication; or

less intensive treatment aimed at managingbracken at low levels.

All follow up treatments need the appropriatecommitment of resources to ensure success andthis should be considered before starting thecontrol programme.

Mechanical methods

Cutting The aim is to cut twice each season.

First cut in about mid-June (mid-July if ground-nesting birds may be present) when the brackenis 50-75 cm high (this cut may have to be later inthe uplands) and again six weeks later. Thistwice yearly cutting is likely to be required for atleast 3 years. An alternative is a single cut in lateJuly, repeated for at least 5 years. The two-cutsystem allows earlier access to vegetation underthe bracken by grazing stock as well as furtherweakening the rhizome by forcing additionalgrowth during the season.

Cutting will need to be repeated when thebracken shows signs of recovery. Completeeradication will not be achieved by cutting alone.Considerations about whether to cut or notshould be made in respect to ground-nestingbirds. On sensitive archaeological sites, cuttingshould be carried out using hand-held strimmersand it may be possible to remove bracken litteracross small archaeological areas by raking.

On some sites, a follow-up cut can be carriedout using a double-chop forage harvester,provided there are no obstacles or stone/rocksto cause damage. Where possible the forage(including large areas of dense bracken litter)can be collected and used as mulch or sold toplant nurseries. There is evidence that thescraped areas will re-colonise well where densebracken litter has been removed.

Crushing This is less effective than cutting, butis sometimes suitable for difficult terrain whichmight damage cutter blades. It is usually best

carried out repeatedly on young fronds that arebrittle and easily snapped. All Terrain Vehicles(ATV) can be used to treat areas where a largermachine cannot go such as amongst gorse or

under trees. Repeat the treatment for at least 3years if two crushings per season, and 5 years if

only crushed annually.

This technique is useful as a follow-up treatmenton a sprayed areas. Use a flat or ring roller.Special bracken crushing rollers fitted with deepcross-ribs (eg Cuthbertson, Holt), or purpose-built machines (eg Landbase, Bracken Bruisers)may be available locally.

Where tractors or ATVs are unsuitable, considerusing horse-drawn rollers or bracken-bruisers.There is a risk of erosion if this method is used

on sloping ground. It should not be used whereground-nesting birds are present or on sensitivearchaeological sites. Crushing rollers maydamage low level archaeological remains whichare obscured by the height of the bracken. Nocrushing should be undertaken in the proximityof such remains and instead hand-heldstrimmers should be used. This method is alsounlikely to eradicate bracken but can help tokeep it in check.

Livestock treading Winter-feeding can be used

to attract livestock onto the site so that:

bracken buds and developing fronds which areclose to the surface or just emerged aredamaged by stock treading (cattle are moreeffective than sheep); and

the litter is disturbed and broken up (this alsoencourages frost penetration to the rhizomes).

In spring, as new fronds expand, remove thelivestock to prevent bracken poisoning. This isnot a reliable method but can help damage

surviving fronds as a follow-up on sprayedareas. It should not be used where thevegetation is easily damaged by trampling (egheather), where particularly vulnerablearchaeological deposits are located or whereunsightly fencing has to be erected.

Burning of bracken litter is useful to easecultivation and seeding success. Burning ofdead litter without follow-up is of no benefit,constitutes an unnecessary fire risk and mayincrease frond production. Burning may also beunsightly in the landscape.


4/7

Page 4



Ploughing and cultivation On suitable areasbracken cover can be significantly reduced by

ploughing between late June and early August.Aim to invert deep furrows to expose thebracken rhizomes and leave these undisturbedover winter and follow with a spring sowing.Deep tine cultivation in two directions has beenused to successfully controlled bracken withoutploughing. Some regeneration will occur, so afollow-up programme using another methodmust also be used.

This method should not be used on sites with avaluable ground flora or with archaeological

remains. This method can also damage theintrinsic value of the soil being cultivated, and soshould not be used on undisturbed semi-naturaland/or ancient soils. Environmental ImpactAssessment regulations will need to beconsidered.

Chemical methods

Two herbicides are recommended for brackencontrol: asulam (Asulox) and glyphosate.Recommended dose rates for overall applicationare: Asulam 11 litres/ha: Glyphosate 5 litres/ha.

Asulam is selective and has relatively littlepermanent effect on underlying vegetation, but itwill kill other ferns. It is approved for aerialapplication. Glyphosate is cheaper, but being asystemic chemical should only be sprayed inareas of deep litter bracken with little underlyingvegetation as it will kill any grass or heatherpresent. It is not approved for aerial application.Weed-wipers can be used to create selectivitywithin the vegetation canopy. Livestock shouldbe excluded from treated areas until aftersenescence to reduce the risk of brackenpoisoning.

Both chemicals should be applied after full frondexpansion, but before tip die-back. This ensuresmaximum absorption and translocation intobelow-ground rhizomes. This normally occursbetween mid-July and late Septemberdepending on altitude, locality and season. Bothchemicals can achieve > 90% control.

An advantage of glyphosate is that it producesvisible symptoms soon after application allowingtreatment of missed strips in the same season.In all cases, spot treatment of missed areas in

the same season or in the following year and thetreatment of regenerating areas, will

considerably increase the duration of effectivecontrol. Eradication requires annual spottreatment.

Tractor mounted sprayers Spray booms mustbe set high enough for an even coverage of thefronds. Areas to be controlled should be walkedthe previous winter to mark dangerousobstacles. Tractor mounted sprayers should notbe used in the vicinity of sensitive archaeologicalsites.

Aerial application (by helicopter only) Onlyasulam is approved for aerial application.Control by aerial spraying is most successfulwhere there are large areas of uninterruptedbracken, if there is underlying archaeology andon slopes too steep to allow safe use of aground-based vehicle. Where there areobstacles that prevent a constant flying height,control will be poor. The area to be treated eachyear should not exceed the area that can bemanaged by follow-up treatment.

Knapsack spraying Useful for small areas, butlimited by the weight of water carried, the needfor frequent refilling and the effort required tokeeping the boom above the fronds. Suitable forarchaeological sites and for follow-up treatmenton limited areas.

Low volume drift spraying with the MicronUlva Comfortable and easy to use but brackencontrol is less reliable than for other spraymethods. A steady wind of 5 to 10 km per houris required. Asulam is used in mixture with

wetters, eg Adder or Actipron.

Weed wipers Generally, these are ATV ortractor-mounted rotating pressurised systems.Only glyphosate is approved for use in weedwipers.

Spot treatment This approach can be used tocontrol missed areas, fronds of recoveringbracken after an overall spray, or patches thatare inaccessible or otherwise unsuitable fortractor mounted equipment. Both asulam and

glyphosate are approved. They should beapplied to wet the foliage thoroughly, but not tothe point of run-off. Spot-guns and hose and


5/7

Page 5



lance on ATV/quad bikes are suitable applicationmethods.

Mixed mechanical/herbicide methods

A combination of mechanical methods andherbicide application is often effective. Forexample, a single aerial spray will give goodprimary control that can be maintained byregular cutting. Cutting alone may not have beensafe in the previously dense bracken. A winter orlate autumn cut of the dead stems may also helpto increase the uptake of the chemical into therhizome which, if combined with a frost, willweaken the plant still further.

A single cut in the year before sprayingproduces an even canopy, a higher density offronds and more active buds on the rhizome, allof which increase the efficacy of the herbicide.

Long-term control

Mechanical and chemical control can effectivelyreduce bracken infestation, but monitoring andfollow up treatments together with grazingmanagement are essential to maintain control.

Vegetation re-establishmentWhere there is existing valuable ground floravegetation management should be aimed atmaintaining this desired cover. Where there islittle existing ground vegetation, then brackencontrol should be supported by methods to re-instate other vegetation: typically uplandgrassland, heathland or moorland, or onagricultural areas, productive grassland.

The choice of vegetation type should be agreed

prior to starting bracken control and, whereappropriate, should be included within agri-environment agreement objectives. Factors toconsider during vegetation re-establishmentinclude:

Litter disturbance

This can be achieved by burning, incorporation,livestock trampling or removal. All methodsincrease the speed of re-vegetation and can beinitiated before bracken treatment begins.Trampling may be encouraged by the judicious

use of supplementary feeding (including minerallicks), although care should be taken to avoiddamaging other existing semi-natural vegetation.

This option is not appropriate on steep slopessusceptible to soil erosion or on sensitive

archaeological sites.

Seeding

Heather re-instatement requires the use of seedfrom other areas of heathland or moorland. Thiscan be applied as litter (at about 1 tonne/ha) oras cut shoots collected in November orDecember (at 5-15 tonnes/ha). Stabilisation ofthe soil whilst heather establishment takes placecan be accomplished with forestry brashings orwith a nurse sward of suitable grasses (egcommon bentAgrostis capillaris, wavy-hair

grass Deschampsia flexuosa or sheep's fescueFestuca ovina) sown at 20-40 kg/ha (50/50bent/fescue mixture). Recently, a noveltechnique has been developed where cleanedheather seed is pre-treated by smoke/chemicalsto stimulate germination and then broadcast byhydraulic sprayer.

Grass re-establishment

For agriculturally productive grassland, routinepractices can be followed. For upland grazing amix of bents and fescues may be appropriate.Adding a range of wildflowers to the mixture willproduce grassland with higher conservationinterest, although seed and establishment costswill be higher.

Fertiliser and lime

For productive grassland a slow releasephosphate fertiliser with nitrogen may berequired. If soil pH is < 4.5, lime may be appliedto aid grassland establishment and growth.

Recommendations should be based on recentsoil test results, ensuring adequate samplingintensity for the number of fields or area of landbeing treated.

Grazing control

Where vegetation is being re-instated, grazingshould be carefully managed. Reduce or preventgrazing during the establishment phase andcarefully monitor in subsequent seasons to avoidovergrazing. The slower growth of heatherplants means they must be protected from

overgrazing for a longer period, generally fiveyears. Any new fencing should be sited carefullyto avoid damage to archaeological features or


6/7

Page 6



landscape value. On conservation sites, it maybe necessary to exclude rabbits from areas

where heather regeneration is desired. This canbe done by erecting temporary fencing: eitherelectric close-weave fencing (polywire type), orrabbit fencing with overlapped netting pinned ordug into the soil or turf.

Conversion to woodland

In circumstances where it is not environmentallyor agriculturally cost-effective to control bracken,it may be appropriate to plant trees or allownatural succession to woodland and/or scrub.Depending on eventual tree cover, bracken may

be shaded out, although its control will almostcertainly aid establishment during planting. Thepotential for natural succession can be tested byassessing the density of tree and shrubseedlings, with and without litter removal in trialareas. Woodland will not be appropriate onarchaeological sites, or where the existingwildlife or landscape value is greater.

Further information

Natural England Technical Information Notes are

available to download from the Natural Englandwebsite: www.naturalengland.org.uk. Inparticular SIN011 and TIN047:

Bracken

Bracken management: ecological,archaeological and landscape issues andpriorities

For information on other Natural Englandpublications contact the Natural England EnquiryService on 0845 600 3078 or e-mail

[email protected]

This leaflet has been developed from varioussources including the RDS Technical Advice

Note Bracken control, vegetation restoration andland managementthat was originally written by:

PROFESSOR R.J. PAKEMAN, Macaulay LandUse Research Institute, Craigiebuckler,Aberdeen, AB15 8QH, UK. (Fax: 01224 311556,E-mail: [email protected])

Dr M.G. Le DUC & PROFESSOR R.H. MARRS,School of Biological Science, Derby Building,University of Liverpool, PO Box 147, L69 3BX,UK. (Fax: 0151 794 4940, E-mail:[email protected])

Additional material added by I. CONDLIFFE, D.ENRIGHT, M. FROMENT and D. SMALLSHIRE,PAUL LACEY Natural England.

Other information

Scottish Environment Agency, BrackenControl: A Guide to Best Practicewww.sepa.org.uk/publ icat ions/ leaf lets/brac

ken/

Bracken and high brown fritillary butterflieswww.but ter f ly-

conservat ion.org/uploads/high_brown_fr i t i l

lary(1).pdf

Defra, Controlling soil erosionwww.defra.gov.uk/ENVIRONMENT/land/soi l /

pdf /soi lerosion-combinedleaf lets.pdf

Environment Agency, Application to useherbicides in or near waterwww.envi ronment-

agency.gov.uk/commondata/acrobat /wqm1

_f o rm_1797463.p d f

Appendix - Health and Safety, and guidelines for herbicide use

Safety: Working on slopes - spraying and mechanical treatment

No slope is safe.

Use four-wheel drive tractors fitted with approved safety cabs or frames, or appropriate ATVequipment.

Drivers must be experienced in working on steep and uneven ground and be particularly aware ofthe dangers of operating trailed equipment on slopes. Walk the site the winter before treatment orcutting operations are planned to check for hidden obstacles, ditches etc. Beware of buried pipesand cables, and any overhead wires.
http://www.environment-agency.gov.uk/commondata/acrobat/wqm1_form_1797463.pdfhttp://www.environment-agency.gov.uk/commondata/acrobat/wqm1_form_1797463.pdfhttp://www.environment-agency.gov.uk/commondata/acrobat/wqm1_form_1797463.pdfhttp://www.environment-agency.gov.uk/commondata/acrobat/wqm1_form_1797463.pdfhttp://www.environment-agency.gov.uk/commondata/acrobat/wqm1_form_1797463.pdfhttp://www.environment-agency.gov.uk/commondata/acrobat/wqm1_form_1797463.pdfhttp://www.environment-agency.gov.uk/commondata/acrobat/wqm1_form_1797463.pdf


7/7

Page 7



Consult Engineering Consultants for advice if in doubt. A charge will be made for this service.

HealthThere is a possibility that bracken spores are carcinogenic. The H&S Executive recommends that a

suitable face mask should be worn while cutting or working in spore-producing bracken (ie duringlate July, August and September).

Herbicide use

Always follow the instructions on the herbicide label and your COSHH assessment.

Make a preliminary assessment to establish the precautions for safeguarding the environment.

The Code of Practice for the Use of Approved Pesticides in Amenity and Industrial Areas statesthat before use, there should be contact or notification of those responsible for habitats requiringspecial consideration. This requirement can normally be met by liaison with local wildlife trusts.

Environment Agency (EA) must also be consulted. Notification is not necessary on every occasionon which spraying is carried out, but it is the responsibility of the landowner and not the contractor.

Herbicides are likely to be listed as a 'potentially damaging operation' for Sites of Special ScientificInterest (SSSIs). Under the Wildlife and Countryside Acts of 1981 as amended, written agreementmust be obtained from the relevant country agencies (Natural England, Countryside Council forWales, Scottish Natural Heritage), giving 4 months notice, before bracken can be treated inside anSSSI or within mile of one.

Glyphosate is approved for use in or near water, but as far as possible, over-spraying of ditchesand streams should be avoided. A 20 m strip must be left around reservoirs and lakes, with anextra 10 m if drift machines (eg CDA sprayers) are being used. Asulam may also be used as longas contamination is avoided using the same guidelines.

Members of the public must be protected from possible hazards. Rights of way (roads, bridle paths,and footpaths) should not be sprayed and warning signs may be needed to tell people to keep tothem. Signs warning that spraying has been carried out must be posted in areas where there areberries that might be picked.

Aerial application of herbicides requires consultation with the country agencies (Natural England,Scottish Natural Heritage or Countryside Council for Wales) and the EA or SEPA. There must alsobe notification of neighbours and the Chief Environmental Health Officer for the area beforespraying takes place.

Buffer zones for spraying operations close to water courses and areas with a conservationdesignation should be set in consultation with EA and the relevant country conservation agency. Asa guide, aerial spraying requires a 160 m buffer zone with conventional nozzles and a 50 m zonewith raindrop nozzles. Conventional nozzles on tractors or knapsack sprayers require a 20 m buffer

zone, or a 5 m zone if equipped with low-drift nozzles. ULVA requires a 50 m buffer zone.Care must be taken to avoid damage to neighbouring crops by spray drift. In most areas where

bracken is being treated, forestry plantations are the only crops at risk. Most trees are tolerant ofasulam at the normal application rate, although there may be some scorch if young specimens aresprayed directly when actively growing. Western hemlock and willow are more sensitive and shouldnot be sprayed. Glyphosate should never be used near trees except as directed applications.

natural england - bracken tin048 edition 1

Documents