Action: Leave cultivated, uncropped margins or plots (includes 'lapwing plots')
- Nineteen individual studies looked at the effect of uncropped, cultivated margins or plots on wildlife. Seventeen studies from the UK and northwest Europe (six reviews and seven replicated studies of which two were site comparisons, one a before-and-after trial and one was controlled and randomized) found that leaving uncropped, cultivated margins or plots on farmland provides benefits to some or all target farmland bird species, plants, invertebrates, and mammals. These wildlife benefits included increased species richness of plants, bumblebees, species richness and abundance of spiders, abundance of ground-dwelling invertebrates and ground beetles, increased stone curlew breeding population size, northern lapwing hatching success, Eurasian skylark nesting success and the establishment, abundance or species richness of rare arable plant species. A replicated study found northern lapwing, Eurasian skylark, grey partridge and yellow wagtail bred in lapwing plots.
- Two studies (a replicated study and a review) from the UK found that leaving uncropped, cultivated margins or plots on farmland had no effect on 11 out of 12 farmland bird species or ground beetles. A replicated site comparison study in the UK found fewer seed-eating birds on fallow plots for ground-nesting birds in two out of three regions. One review from the UK found evidence that pernicious weeds were more commonly found on uncropped cultivated margins than conservation or conventional headlands. A replicated site comparison from the UK found the proportion of young grey partridges in the population was lower in areas with a high proportion of uncropped cultivated margins and plots.
This intervention can be introduced for ground-nesting birds (sometimes called ‘lapwing plots’), rare arable plants, or both. It may also provide habitat for insects and foraging sites for mammals and seed- and insect-eating birds (Campaign for the Farmed Environment 2011).
Plots or strips are cultivated, but left undrilled. For ground-nesting birds, the plots are usually at least 2 ha in size. They are different from 'skylark plots', which are much smaller and usually created in groups. If this measure is taken in field margins (6 m strips at the edge of arable fields), no fertilizer is applied, and herbicide applications are minimal, with only spot treatment of particular weeds permitted.
See also ‘Provide (or retain) set-aside areas’, for rotational or long-term fallow land at the field scale not cultivated or implemented specifically for ground-nesting birds.
See also ‘Sow rare or declining arable weeds’ for a study of different management options that could also apply to uncropped, cultivated margins.
Campaign for the Farmed Environment (2011) Guide to voluntary measures 2011 edition. Campaign for the Farmed Environment, Warwickshire.
Supporting evidence from individual studies
A small study of the margin of an arable field in the Breckland Environmentally Sensitive Area, in the east of England (Hawthorne et al. 1998) found that the uncropped margin supported more adult ground beetles (Carabidae) than the cropped margin or the crop, and more larvae (uncropped: 38 larvae/trap, cropped: 12 larvae/trap). The ground beetle Bembidion lampros was significantly more abundant in the 6 m uncropped margin (reduced pesticides) than the cropped margin (fully sprayed) or crop, and tended to move into the crop. Catches of Pterostichus melanarius were consistently higher in the crop than the uncropped and the cropped margin. Agonum dorsale abundance was lowest in the uncropped margin, and tended to move from field boundaries into the crop. The uncropped margin had significantly less vegetation than the cropped margin. The field margin was divided into two blocks, each with both treatments (120 m-long). Ground beetles were sampled with five pitfall traps in each: plot (20 m apart), 32 m into the adjacent crop and field boundary block. Directional traps, an ‘H’ shape (2 m-long) barrier with five pitfalls on each side, were constructed to investigate movement at the field boundary-margin and margin-crop interface in each replicate strip. Traps were emptied weekly from April-August 1991.
A 1999 review of research into uncropped strips in northwest Europe (de Snoo & Chaney 1999) found that biodiversity was enhanced by establishing uncropped strips. Two studies found that ground-dwelling invertebrates were more abundant in uncropped strips than unsprayed cereal strips (Hawthorne & Hassall 1994, White & Hassall 1994). Another reported that ground beetles (Carabidae) were more abundant in the uncropped strip and adjacent crop than in the crop adjacent to sprayed and unsprayed crop strips (Cardwell et al. 1994). Spider (Araneae) species richness and abundance was also reported to be higher in uncropped strips than unsprayed cereal strips by one study (White & Hassall 1994). An additional study found positive results for gamebirds, songbirds and hares Lepus spp. (Anon 1990).
Anon (1990) Öko-Wertstreifen in Ackerbaugebieten. Jagd und Hege, 12, 5-7.
Cardwell C., Hassall M. & White P. (1994) Effects of headland management on carabid beetle communities in Breckland cereal fields. Pedobiologia, 38, 50-62.
Hawthorne A. & Hassall M. (1994) Effects of management treatments on carabid communities of cereal field margins. Pages 313-318 in: N.E. Boatman (ed.) Field Margins: Integrating agriculture and conservation. BCPC monograph No. 58.
White P. C.L. & Hassall M. (1994) Effects of management on spider communities of headlands in cereal fields. Pedobiologia, 38, 169-184.
A 2002 review (Evans et al. 2002) of two reports (Wilson et al. 2000, ADAS 2001) evaluating the effects of the Pilot Arable Stewardship Scheme in two regions (East Anglia and the West Midlands) in the UK, from 1998 to 2001 found that grass margins benefited plants, bumblebees Bombus spp., bugs (Hemiptera) and sawflies (Symphyta), but not ground beetles (Coleoptera). The grass margins set of options included uncropped cultivated wildlife strips, sown grass margins, naturally regenerated margins and beetle banks. The review does not distinguish between these options, although the beneficial effects were particularly pronounced on uncropped cultivated wildlife strips for all four groups. The effects of the pilot scheme on plants and invertebrates were monitored over three years, relative to control areas. Grass margins were implemented on total areas of 361 and 294 ha in East Anglia and the West Midlands respectively.
Wilson S., Baylis M., Sherrott A. & Howe G. (2000) Arable Stewardship Project Officer Review. F. a. R. C. Agency report.
ADAS (2001) Ecological evaluation of the Arable Stewardship Pilot Scheme, 1998-2000. ADAS report.
A replicated study in the summers of 1999-2000 comparing ten different conservation measures on arable farms in the UK (Critchley et al. 2004) found that uncropped, cultivated margins appeared to be one of the three best options for conservation of annual herbaceous plant communities. Wildlife seed mix (largely sown for birds) and no fertilizer conservation headlands were the other two options. Uncropped, cultivated margins were dominated by annual plant species. Of the ten measures, they had the highest numbers of annual and herbaceous plant species, unsown crops (crop volunteers), bare ground and litter, and the lowest cover and species richness of grasses. Cultivated spring fallows had fewer plant species than cultivated margins, but relatively high total plant cover, and over 50% cover of monocotyledonous plants (mainly grasses). The average numbers of plant species in the different conservation habitats were uncropped cultivated margins 6.3, wildlife seed mixtures 6.7, undersown cereals 5.9, naturally regenerated grass margins 5.5, no-fertilizer conservation headlands 4.8, spring fallows 4.5, sown grass margins 4.4, overwinter stubbles 4.2, conservation headlands 3.5, grass leys 3.1. Plants were surveyed on a total of 294 conservation measure sites (each a single field, block of field or field margin strip), on 37 farms in East Anglia (dominated by arable farming) and 38 farms in the West Midlands (dominated by more mixed farming). The ten habitats were created according to agri-environment scheme guidelines. Vegetation was surveyed once in each site in June-August in 1999 or 2000, in thirty 0.25 m2 quadrats randomly placed in 50-100 m randomly located sampling zones in each habitat site. All vascular plant species rooted in each quadrat, bare ground or litter and plant cover were recorded.
A controlled trial on paired sites in 2003 on Arable Stewardship Pilot Scheme farmland in the UK (Pywell et al. 2005) found that bumblebee Bombus spp. foraging activity and species richness were significantly enhanced on uncropped, regularly cultivated field margins where natural regeneration had been allowed to take place for five years, compared to sites of conventionally managed cereal. The uncropped margins had significantly more plant species than either conservation headlands or uncropped margins sown with a wildflower seed mix. However, two species considered to be pernicious weeds, spear thistle Cirsium vulgare and creeping thistle C. arvense were key forage plants for the bumblebees, so this option may lead to conflict between agricultural and conservation objectives. Bumblebee numbers were estimated through paired surveys on field margins and conventionally-managed cereal field margins. Foraging bumblebees were recorded along 100 x 6 m transects and the plant species on which bumblebees were observed feeding was noted. Twenty 0.5 x 0.5 m quadrats were used along the bumblebee transects to record the presence of all plant species.
A replicated before-and-after trial in 1997-2000 on cultivated headlands in arable fields at three sites in Suffolk, Hampshire and North Yorkshire, UK (Critchley et al. 2006) found that plant species richness increased when headlands were left uncropped with no inputs. In July 1997, before cropping ceased, the three sites had 33, 70 and 19 plant species respectively. When uncropped, the number of species found each year, over the three years of the trial, increased to 75-85 93-94 and 55-59 at the three sites respectively. Although the main components of the vegetation were target annual and broadleaved plants, there was also an increase in perennial plants (from 1-3% to 27-40% cover) and monocotyledons (mainly grasses) (1-10% to 18-31%), and the authors note that these may need to be controlled. Treatments were replicated three times (in 6 x 6 m plots) at each site. Plants were surveyed each July in 32 quadrats (0.5 x 0.5 m) in each plot.
A replicated study in 1999 and 2003 on 256 arable and pastoral fields across 84 farms in East Anglia and the West Midlands, UK (Stevens & Bradbury 2006) found that only one out of 12 farmland bird species, reed bunting Emberiza schoeniclus, was strongly and positively associated with uncropped, cultivated strips. No other species showed a strong association (positive or negative) with the strips.
A replicated site comparison study in the UK (Critchley et al. 2007) found that uncropped, cultivated margins had more plant species than other field margin types, and increased plant species richness over time in one (but not all) areas. In a national survey of field margins under the Countryside Stewardship Scheme, 39 uncropped regularly cultivated field margins had more plant species (31 species/margin) than 72 control margins (8 species/margin) and 78 conservation headlands (11-17). Thirty-nine margins that were uncropped and cultivated for one year (called ‘spring fallow’) had 20 plant species on average. In the pilot Arable Stewardship Scheme in two English regions (East Anglia and the West Midlands), 24 uncropped cultivated strips had greater numbers of perennial plants and pernicious weeds after four years (measured in 1999 and 2003), but the total number of species did not increase (7-8 plant species/margin). By contrast, there was a substantial increase in number of plant species in 32 uncropped cultivated margins in the Brecklands Environmentally Sensitive Area (ESA) between 1996 (12 species/margin) and 2004 (18 species/margin). Here the number of pernicious weed species did not increase. Plants were surveyed in either thirty 0.025 m2 quadrats within a 100 m sampling zone or twenty 10 x 10 cm quadrats (only used in Brecklands ESA). Percentage cover and plant species were recorded in each quadrat.
A 2007 review of a Countryside Stewardship Scheme in southern England (Evans & Green 2007) found that the population of Eurasian thick-knees (stone curlew) Burhinus oedicnemus increased from 71 breeding pairs in 2000 to 103 in 2005, following the creation of 156 stone curlew plots over the study period typically located close (<1 km) to pasture, pig farms or other food sources and away from edges of fields. A further 51 plots were created in 2006 under Higher Level Stewardship. The UK stone curlew population increased from 160 pairs in the 1980s to 300 pairs in 2005. Stone curlew plots consisted of 1-2 ha of arable or set aside land cultivated to create a ‘rough fallow’ in spring.
A 2007 review of published and unpublished literature (Fisher et al. 2007) found experimental evidence of benefits of fallow plots to plants, from one study on Salisbury Plain Training Area, UK (Walker et al. 2001). Stone curlew plots, not sprayed with herbicide, hosted rare arable weed species including dense-flowered fumitory Fumaria densiflora and red hemp nettle Galeopsis angustifolia.
Walker K., Pywell R.F., Carvell C. & Meek W.R. (2001). Arable weed survey of the Salisbury Plain Training Area. Abbots Ripton: Centre for Ecology and Hydrology.
A replicated, controlled study in the breeding seasons of 1999-2000 on 28 farms in western England (Sheldon et al. 2007) found that 85% of 34 northern lapwing Vanellus vanellus nests successfully hatched at least one chick on fields with cultivated ‘lapwing plots’, compared to 64% of 154 nests on all other field types. Nest survival estimates were also significantly higher (99% daily survival vs 95-96% on spring cereals, stubbles and grass habitats), and no nests were lost to agricultural operations, compared to over 50% in other fields.
At Ranscombe Farm, a nature reserve managed for arable plants in the north Kent Downs, UK (Still 2007), two to three kilometres of uncropped cultivated margins yielded populations of one or two species of rare arable plants in the first year of establishment. Two kilometres of margins established in autumn 2004 grew populations of hairy mallow Althaea hirsuta and broad-leaved cudweed Filago pyramidata in 2005. Three kilometres of margins established in spring 2006 supported approximately 10,000 broad-leaved cudweed plants, the second largest population in the UK.
A study in 2003-2005 in Cambridgeshire, UK (Stoate & Moorcroft 2007) found that the nesting success of Eurasian skylark Alauda arvensis was significantly higher in a field that was fallowed after harvest, compared to in cereal crop fields (84% success in the fallow field vs 35%), whilst the number of nests in the field increased from two to eight following the fallow. Overwinter counts of yellowhammer Emberiza citrinella, reed bunting E. schoeniclus, linnet Carduelis cannabina and skylark on the fallow field were also far higher than in previous years.
A replicated, controlled, randomized site comparison study of field margins at 39 sites in England (Walker et al. 2007a) (same study as (Walker et al. 2007b)) found that uncropped cultivated margins significantly increased rare arable plants. Uncropped cultivated margins had significantly higher numbers of rare arable plants (1.4/sample zone) than conservation headlands (0.1), no-fertilizer conservation headlands (0.7), spring fallow (0.6) and the crop (0.1). A total of 145 records of 34 rare arable plants were found on the 195 field margins, including four UK Biodiversity Action Plan species. Three species occurred on 7-10% of sites, a further 19 occurred on 1-5% and the remainder were found on just one margin. In total 25 rare arable plants were recorded on uncropped margins, 18 on no-fertilizer conservation headlands and 16 on spring fallow. There were no significant differences in rare arable plant diversity at 1, 3 or 5 m from the field edge within margin types. There were significant regional differences in diversity. One of each margin type and an adjacent control was randomly selected in thirty-nine 20 x 20 km squares in England. Rare arable plants were sampled in 10 quadrats (0.5 x 0.5 m) at three distances (1, 3 and 5 m) from the field edge within a 100 x 6 m sample zone in June-July 2005.
A replicated, controlled, randomized site comparison study in 2005 of Countryside Stewardship Scheme field margin options across England (Walker et al. 2007b) (same study as (Walker et al. 2007a)) found more arable plant species on uncropped cultivated margins (7.5 species on average) than on ‘spring fallow’ plots (4.3 species), conservation headlands (2.4-4.1 species) or cereal crop control (1.4 species). Thirty-four rare arable plant species were recorded, only 12 of which were found in over 2% of sites. Uncropped margins had significantly more rare species (1.4 species/margin on average) than the other three options (0.2-0.8 species/margin). A total of 39 randomly selected 20 x 20 km squares throughout England were visited to sample: uncropped cultivated margins, spring fallow (cultivation of stubble in whole/part field) and conservation headlands with and without fertilizer. A conventionally managed cereal crop (control) was also sampled at each of the farms visited. A total of 195 field margin agreements were surveyed during June and July 2005. All plant species and 86 rare arable plants were investigated.
A 2008 review of control methods for competitive weeds in uncropped cultivated margins managed to maintain uncommon arable plant populations in the UK (Critchley & Cook 2008) found that specific management regimes can reduce abundance of pernicious weeds in margins. One study found pernicious weeds were more likely in uncropped cultivated margins than in conservation or conventional headlands (Critchley et al. 2004). Abundance of perennial plants tended to increase if uncropped cultivated margins were not cultivated annually in two studies (Critchley 1996b, Critchley 2000). However five studies found weeds also build up on margins cultivated annually, particularly with the same annual cultivation regime (Critchley 1996a,b, Critchley et al. 2004, Critchley et al. 2006, Still & Byfield 2007). One study found cutting twice in spring decreased annual broadleaved plants in uncropped cultivated margins (Marshall 1998).
Critchley C.N.R. (1996a) Monitoring as a feedback mechanism for the conservation management of arable plant communities. Aspects of Applied Biology 44, 239-244.
Critchley C.N.R. (1996b) Vegetation of arable field margins in Breckland. PhD thesis, University of East Anglia.
Marshall E.J.P. (1998) Guidelines for the Siting, Establishment and Management of Arable Field Margins, Beetle Banks, Cereal Conservation Headlands and Wildlife Seed Mixtures. IACR report to MAFF.
Critchley C.N.R. (2000) Ecological assessment of plant communities by reference to species traits and habitat preferences. Biodiversity and Conservation 9, 87-105.
Critchley C.N.R., Fowbert J.A. & Sherwood A.J. (2004) Botanical assessment of the Arable Stewardship Pilot Scheme, 2003. ADAS report to the Department for Environment, Food and Rural Affairs April 2004.
Still K. & Byfield A. (2007) New Priorities for Arable Plant Conservation. Plantlife, Salisbury.
A replicated study in 2007 (Chamberlain et al. 2009) found that northern lapwing Vanellus vanellus used 39% of 212 lapwing plots on 180 farms across England, with breeding suspected on 25% of plots. In addition, Eurasian skylark Alauda arvensis, grey partridge Perdix perdix and yellow wagtail Motacilla flava were recorded breeding in 73%, 17% and 6% of plots respectively. There were no significant differences in lapwing occurrence or breeding in plots managed under Higher Level Stewardship compared with those under the Countryside Stewardship Scheme. Lapwing occurrence decreased if there was woodland adjacent, and the probability of breeding increased with the proportion of bare ground present on plots. Skylarks were less likely to be found on plots near hedgerows.
A 2009 literature review of agri-environment schemes in England (Natural England 2009) found that spring and summer fallows provided nesting habitats for northern lapwing Vanellus vanellus, with 40% of fallow plots used by lapwings and breeding suspected on 25% plots (Chamberlain et al. 2009). In addition, the number of breeding pairs of Eurasian thick-knee (stone curlew) Burhinus oedicnemus in southern England increased from 63 in 1997 to 103 in 2005 following the implementation of a Countryside Stewardship Scheme ‘special project’ which included the provision of fallow plots. One study (Walker et al. 2007b) found that 264 plant species typically found in disturbed or arable habitats, including 34 rare and uncommon arable plants, were recorded in three agri-environment scheme options: uncropped cultivated margins (highest diversity), spring fallow, conservation headlands (lowest diversity).
A replicated site comparison study from 2004 to 2008 in England (Ewald et al. 2010) found a lower proportion of young grey partridges Perdix perdix in the population in 2007 on sites with a high proportion of uncropped cultivated margins and plots. There were no significant relationships with changes in partridge density, brood size or overwinter survival. Spring and autumn counts of grey partridge were made at 1031 sites across England as part of the Partridge Count Scheme.
A replicated site comparison study in 2008 and 2009 on farms in three regions in England (Field et al. 2010) found that in two of the three regions, Higher Level Stewardship fallow plots for ground-nesting birds had significantly fewer seed-eating farmland songbirds than conventional crop fields during summer. On farms in East Anglia and the Cotswolds, there were approximately 2.5 birds/ha on crops compared to 1 bird/ha on fallow plots. However, in a third region, the West Midlands, more seed-eating farmland birds were recorded on fallow plots than in crop fields (1.5 birds/ha on fallow plots compared to <0.5 birds/ha on crops). The group of birds analysed included tree sparrow Passer montanus and corn bunting Emberiza calandra, but not grey partridge Perdix perdix. Surveys were carried out in the summers of 2008 and 2009, on 69 farms with Higher Level Stewardship in East Anglia, the West Midlands or the Cotswolds and on 31 farms across all three regions with no environmental stewardship.
- Hawthorne A.J., Hassall M. & Sotherton N.W. (1998) Effects of cereal headland treatments on the abundance and movements of three species of carabid beetles. Applied Soil Ecology, 9, 417-422
- de Snoo G.R. & Chaney K. (1999) Unsprayed field margins - what are we trying to achieve? Aspects of Applied Biology, 54, 1-12
- Evans A.D., Armstrong-Brown S. & Grice P.V. (2002) The role of research and development in the evolution of a 'smart' agri-environment scheme. Aspects of Applied Biology, 67, 253-264
- Critchley C., Allen D., Fowbert J., Mole A. & Gundrey A. (2004) Habitat establishment on arable land: assessment of an agri-environment scheme in England, UK. Biological Conservation, 119, 429-442
- Pywell R.F., Warman E.A., Carvell C., Sparks T.H., Dicks L.V., Bennett D., Wright A., Critchley C.N.R. & Sherwood A. (2005) Providing foraging resources for bumblebees in intensively farmed landscapes. Biological Conservation, 121, 479-494
- Critchley C.N.R., Fowbert J.A. & Sherwood A.J. (2006) The effects of annual cultivation on plant community composition of uncropped arable field boundary strips. Agriculture, Ecosystems & Environment, 113, 196-205
- Stevens D.K. & Bradbury R.B. (2006) Effects of the Arable Stewardship Pilot Scheme on breeding birds at field and farm-scales. Agriculture, Ecosystems & Environment, 112, 283-290
- Critchley C.N.R., Walker K.J. & Pywell R.F. (2007) The contribution of English agri-environment schemes to botanical diversity in arable field margins. Aspects of Applied Biology, 81, 293-300
- Evans A.D. & Green R.E. (2007) An example of a two-tiered agri-environment scheme designed to deliver effectively the ecological requirements of both localised and widespread bird species in England. Journal of Ornithology, 148, S279-S286
- Fisher G.P., MacDonald M.A. & Anderson G.Q.A. (2007) Do agri-environment measures for birds on arable land deliver for other taxa? Aspects of Applied Biology, 81, 213-219
- Sheldon R.D., Chaney K. & Tyler G.A. (2007) Factors affecting nest survival of northern lapwings Vanellus vanellus in arable farmland: an agri-environment scheme prescription can enhance nest survival. Bird Study, 54, 168-175
- Still K.S. (2007) A future for rare arable plants. Aspects of Applied Biology, 81, 175-182
- Stoate C. & Moorcroft D. (2007) Research-based conservation at the farm scale: development and assessment of agri-environment scheme options. Aspects of Applied Biology, 81, 161-168
- Walker K.J., Critchley C.N.R. & Sherwood A.J. (2007) The effectiveness of new agri-environment scheme options in conserving rare arable plants. Aspects of Applied Biology, 81, 301-308
- Walker K.J., Critchley C.N.R., Sherwood A.J., Large R., Nuttall P., Hulmes S., Rose R. & Mountford J.O. (2007) The conservation of arable plants on cereal field margins: an assessment of new agri-environment scheme options in England, UK. Biological Conservation, 136, 260-270
- Critchley C.N.R. & Cook S.K. (2008) Long-term maintenance of uncommon plant populations in Agri-environment Scheme in England. Phase 1 Scoping Study. Defra/ADAS report.
- Chamberlain D., Gough S., Anderson G., MacDonald M., Grice P. & Vickery J. (2009) Bird use of cultivated fallow 'lapwing plots' within English agri-environment schemes. Bird Study, 56, 289-297
- Natural England (2009) Agri-environment schemes in England 2009 A review of results and effectiveness. Natural England report.
- Ewald J.A., Aebischer N.J., Richardson S.M., Grice P.V. & Cooke A.I. (2010) The effect of agri-environment schemes on grey partridges at the farm level in England. Agriculture, Ecosystems & Environment, 138, 55-63
- Field R.H., Morris A.J., Grice P.V. & Cooke A.I. (2010) Evaluating the English Higher Level Stewardship scheme for farmland birds. Aspects of Applied Biology, 100, 59-68