Habitat Action Plans Summary

Habitat Action Plans - Cereal Field Margins

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The national habitat action plan defines a cereal field margin as the strip of land between the cereal crop and the field boundary (extending a limited distance into the crop), which is managed to create conditions suitable for farmland species. Although the structure of this land can take several forms, the four most common are:

  • A 6 m 'Wildlife Strip' separated from the crop by a 1 m 'Sterile Strip' - in this case the wildlife strip is cultivated once a year, but not cropped; and the sterile strip is maintained so as to prevent arable weeds spreading into the crop from the wildlife strip.
  • A 6 or 12 m 'Conservation Headland' forming the outer edge of the crop, separated from the field boundary or other vegetation by a 1 m 'Sterile Strip' - in this case the conservation headland is cropped with cereals, but managed with reduced input levels so as to be more suitable for wild arable plants and invertebrates.
  • A 'Wildlife Strip' separated from a 'Conservation Headland' by a 'Sterile Strip' - in this case all three zones are managed as described above.
  • Game crops, stubble or grassland fallows lying between the annually cropped land and the field boundary.


  • Cereal field margins are particularly important habitats for rare arable plants (including pheasant's eye, cornflower, broadleaved spurge, corn parsley, shepherd's-needle and narrow-fruited cornsalad), many species of which have been in marked decline in recent times. However, management to assist these plants also has the result of encouraging a wide range of insects (e.g. butterflies, grasshoppers and plant bugs), together with birds (e.g. grey partridge, quail and corn bunting) and mammals (e.g. brown hare).
  • Field margins may also provide an opportunity to control invasive weed species without having a major impact on farm profits, by utilising less productive land to produce a barrier between the crop and problem weeds in the field boundary or on adjacent land.

Legal Protection

  • The Food and Environment Protection Act 1985 (FEPA) makes it illegal to spray pesticides into hedge bases unless there is a specific label recommendation or off-label approval.
  • Current procedures for pesticide registration and review prevent some compounds being used on the outermost 6 m of the crop, in order to to prevent overspraying of watercourses and damage to adjacent habitats.

Current Status

Estimates suggest that there are approximately 400,000 km of cereal field edge in the UK; therefore, if all such fields incorporated an appropriately managed margin 6 m wide it would correspond to an area of around 200,000 ha (600,000 ha at 12 m). Clearly therefore, there is the potential to place considerable land into environmentally sensitive management programmes.

Threats And Issues

The wildlife value of cereal crops is reduced by:

  • Intensification of cereal production - including the use of herbicides to produce a weed free monoculture, and the summer use of insecticides, both of which are a threat to biodiversity.
  • Winter cropping - the loss of winter stubbles associated with the shift towards winter sown crops.
  • Simplified rotations - reductions in the production of cereals in rotation with other land covers (such as grass leys and fallows) has had a negative impact on many species.
  • Reduction in the undersown area - undersown cereal crops are important for overwintering sawflies, but their use has reduced in association with the switch to winter sown crops.
  • Geographical retreat - the extent to which cereals are grown in northern and western parts of the country has reduced (particularly in Less Favoured Areas - LFAs).

Objectives (As Pertinent To Agriculture)

The national habitat action plan specifies the following objective:

  • To "maintain, improve and restore by management the biodiversity of some 15,000 ha of cereal field margins on appropriate soil types in the UK by 2010" - where 15,000 ha is the area that experts believe to be necessary for the maintenance, improvement and restoration of biodiversity, and it includes the conservation management of both rare arable flowers (generally found on drier, less fertile soils) and grass margins (found on a wide range of soils).

Conservation Advice

More than 50% of British arable land is in cereal production, and as a result the majority of the research carried out into the techniques appropriate to, and the benefits, of field margin management, have involved cereal fields. Consequently, the national habitat action plan is targeted towards cereal rather than arable field margins. Nevertheless, although the benefits of other forms of arable field margin are less clearly understood, many of the measures applicable to cereal field margins are likely to be more widely beneficial. In all cases however, expert advice should be sought before proceeding (e.g. FWAG, the Game Conservancy Trust).

1) Creating a margin

  • Establishment - the field margin can most easily be established at ploughing, for instance by turning a furrow in towards the crop. This edge should then be maintained in subsequent years.
  • Width - it is recommended (FWAG, No Dateb) that a strip at least 1 m wide, be left unaffected by cultivations, fertilisers or pesticides, around all arable crops (1.5 m is the legal minimum along field edge footpaths).
  • Natural regeneration - where a suitable seed bank is available a managed (by careful cutting and the controlled use of herbicides) process of natural regeneration may be effective.
  • Sown grass strips - a carefully chosen seed mixture consisting of species native to the locality and suited to the planned management regime should be adopted. Suitable species may include Red fescues, Meadow grasses, Crested Dogstail and Timothy (particularly on light soils); and Cocksfoot can quickly form tussocks that give cover to both insects and mammals. Rye grass on the other hand is competitive but of low conservation value.
  • Sown wildflower margins - again species combinations that are native to the location should be selected.  A ratio of 80% grass to 20% flower seed (by weight) is usually adequate, but it is possible to get away with 90%:10% (flower seed being significantly more expensive than grass seed).
  • Broad-leaved species - a mixture of grasses and broad-leaved plants may be more difficult to establish, but may form a stable community requiring little maintenance, and which forms an effective barrier to weeds.
  • Sowing - the seed rate will be determined by local conditions such as soil fertility. However, in general it is a compromise between the need to encourage species diversity (aided by low rates: 20-25 kg/ha) and the need to ensure a tight sward that will prevent weed invasion (aided by high rates: 30-35 kg/ha). Autumn sowing into a fine firm seed bed is thought to be most reliable (Wilmot Pertwee, No Date), with a ring rolling before and after sowing. Seed is best left on the surface.
  • Soil fertility - farmland soils are generally more fertile than natural soils, and as a result the success of some species may be limited by competition, and there may be a requirement for frequent cutting to control growth.
  • Sterile strips - should always be taken from the cropped land.

2) Margin management

i) General

  • Drift - the drift of sprays and fertilisers into the field margin (and hedge bottom) should be prevented.

ii) Wildlife/grass strips

  • Cutting - a variety of management strategies, for instance keeping the grass closest to the crop short while allowing longer grass (preferably including tussock forming species) to develop further away, will encourage biodiversity. A cut (or two) early in the season (April/May) opens up the grasses allowing flowering plants to flourish within the grasses. For herb rich mixes a cut late in the season (August/September) removes the seasons growth, thereby encouraging subsequent new growth. Cuttings should always be removed, and if possible the area should be grazed after the late cut. Where a tussocky mix has been sown, cutting may only be required every few years rather than annually.
  • Herbicides applications - if necessary this should preferably be carried out by spot treating affected areas. The selection of resistant species will also be important if the use of herbicides is planned. Barren brome, which can be a serious problem in field margins can be controlled using not more than one application a year of Fusilade 250 EW. Selectivity is ensured by spraying in November or December, when the brome is present as seedlings or small plants, and non-target species are large and well-established. This technique will also control black-grass and wild oats, but should not be carried out every year as it will eventually weaken non-target species of grass. A well established sward is the preferable means of weed control.

iii) Conservation headlands

  • Agrochemicals - the use of agrochemicals should be restricted in this area, although selective pesticides may be used to control grass weeds, cleavers, virus vectors and diseases.
  • Ploughing - this is recommended for the conservation headland, particularly on heavy soils or where grass weeds are a problem. Avoid turning the furrow onto the grass strip, since this can provide the ideal habitat for annual weeds.
  • Rare arable wildflower strips - where such species are present, reduced (or even zero) additions of nitrogen fertiliser may be advisable.

iv) Sterile strips

  • Rotovation - this can be an effective technique in areas badly infested with weeds, if carried out frequently enough to prevent them becoming established. However, it requires machinery with a narrow width, and may often have to be done more than once a year.
  • Mowing - tight mowing of grass also relies on the availability of suitably narrow machinery and may need to be done more than once a year. However, a strip of this sort can provide a more effective barrier to weeds than a bare sterile strip.
  • Herbicides - if herbicides are to be used, a skirted boom must be used to prevent spray drift. Although persistent chemicals only require one application per year, they are generally more likely to cause damage to the environment, than non-persistent chemicals; consequently, the latter should normally be used.

3) Support and assistance

Support for the management of cereal field margins may be available from a number of sources, including:

  • Agri-environmental schemes - cereal field margins are targeted under a number of agri-environmental schemes including the Environmentally Sensitive Areas (ESA) scheme, Countryside Stewardship (England) and Tir Cymen (Wales).
  • Set-aside - the requirements of set-aside can be met by setting-aside field margins with a minimum width of 20 m.
  • Other - Some areas are also managed under initiatives encouraged by the Game Conservancy Trust. In most cases no payment is received, but advice is available from a Field Advisor employed by the Trust (with support from government).


At the national level, the habitat action plan for cereal field margins is being led by the Department for the Environment, Food and rural Affairs (Defra). Contact Ann Davies (Tel.: 020 7238 6448).

Other Biodiversity Action Plans Known To Cover This Habitat

Eastern England

East Midlands
National Forest
North West England 

South East England

West Midlands
Birmingham & the Black Country
Yorkshire and the Humber

Related Action Plans


Ancient and/or species rich hedgerows


Brown hare
Grey partridge
Song thrush
Tree sparrow

References And Further Information

Andrews, J. and Rebane, M. (1994). Farming & Wildlife: A Practical Management Handbook. The Royal Society for the Protection of Birds, Sandy, UK.

FWAG. (No Datea). Hedges and Field Boundaries. Farming and Wildlife Advisory Group, Kenilworth, UK.

FWAG. (No Dateb). Farming and Field Margins. Farming and Wildlife Advisory Group, Kenilworth, UK.

FWAG. (No Datec). Arable Farming. Farming and Wildlife Advisory Group, Kenilworth, UK.

The Game Conservancy Trust. (No Date). The Management of Field Margins and Conservation Headlands. The Game Conservancy Trust, Fordingbridge, UK.

Hill, D.A., Andrews, J., Sotherton, N.W. and Hawkins, J. (1995). Farmland. In: Managing Habitats for Conservation. (Sutherland,. W.J. and Hill, D.A.). Cambridge University Press, cambridge, UK.

Sotherton, N. and Page, R. (1998). A Farmer's Guide to Hedgerow and Field Margin Management. Game Conservancy Limited, Fordingbridge, UK.

UK Steering Group. (1995). Biodiversity: The UK Steering Group Report, Volume 2: Action Plans. HMSO, London.

Wilmot Pertwee. (No Date). Field Margins - Making Them Work and Pay . Wilmot Pertwee, Aylesford, UK.

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