Importance for wildlife

Up to 75% of the biodiversity within an arable field is found in the margins, regardless of the farming practice. The margins link farmland habitats and buffer them against farm operations. They provide nesting sites for ground-nesting birds and hunting areas for barn owls and other birds of prey. The margins create over-wintering habitat for insects and spiders. Wild flower strips within margins attract important pollinators such as bees and hoverflies. They are important refuges for wildlife and conservation sites for rare arable plants.

Important associated species

Birds
House Sparrow, Stone Curlew, Woodlark, Corn Bunting, Eurasian Tree Sparrow, Grey Partridge, Yellow Wagtail, Turtle Dove, Linnet, Skylark, Yellowhammer, Bullfinch, Reed Bunting, Barn Owl

Mammals
Harvest Mouse, Hedgehog, Brown Hare, Pipistrelle Bat, Soprano Pipistrelle

Reptiles and Amphibians
Great Crested Newt, Common Toad

Bees and Wasps
Brown-banded Carder Bee, Large Garden Bumblebee, Red-shanked Carder Bee

Beetles
Necklace Ground Beetle, Brush-thighed Seed-eater, Stag Beetle

Moths
Grey Carpet (Brecks), Pale Shining Brown, Four-spotted Moth

Mosses and Liverworts
Texas Balloonwort

Plants
Basil Thyme, Red Hemp-nettle, Grape-hyacinth, Fingered Speedwell, Annual Knawel, Corn Buttercup, Cornflower, Fine-leaved Sandwort, Shepherd’s Needle (boulder clay areas), Small-flowered Catchfly, Spreading Hedge-parsley, Red-tipped Cudweed, Broad-leaved Cudweed

*Suffolk Priority species

Factors affecting habitat in Suffolk

• Intensive arable production involves high use of herbicides and insecticides.
• Changes in farming practices including a shift to winter cropping and so the loss of winter stubble which previously provided food over-winter for birds such as corn buntings and yellowhammers.
• Changes in traditional management such as the reduction of grass in the rotation with arable crops.
• Agri-environmental schemes and Cross Compliance regulations.
• Campaign for the Farmed Environment aims to help farmers support the natural environment, whilst farming productively.

Habitat management advice

• Maintain a mosaic of different habitats by retaining features such as boundary hedges, woodland, grass banks and bare ground.
• Create beetle banks from sown strips of native grasses within the cropped area. Mow regularly every 2 years or so and do not spray. These provide shelter for beneficial beetles and spiders that prey on arable crop pests.

Types of margin / in-field options

a) Uncropped cultivated margins

Lightly cultivated in spring or autumn to provide habitat for rare arable plants and foraging sites for seed-eating birds. No fertilisers or manures, herbicides only applied to spot treat or weed wipe to control pernicious weeds.

b) Conservation headlands

Provides a food supply and habitat for birds, arable plants and insects within the growing crop. No fertiliser or manure before the crop is drilled. No insecticides applied between 15th March and the following harvest; herbicide application is restricted; may be left unharvested.

c) Permanent grass margins

Provides varied habitat on arable or grassland; coarse tussocky grass is an important habitat for over-wintering insects and small mammals; finer grass and flowering plants provide nectar, seed and more open habitat. Field corner management provides undisturbed grassy areas, scrub and grass margins.

d) In-field arable options

Wild bird seed mixture plots, nectar flower mixture plots, beetle banks, skylark plots, overwintered stubble, low input cereal and/or reduced herbicide cereal.

For detailed advice contact: Suffolk FWAG tel: 01728 748030 or RSPB local adviser tel: 01603 697586

Vision for Suffolk

1. Improve knowledge of the extent and quality of arable field margins.
2. Maintain the existing extent of arable field margins to ensure no net loss.
3. Re-create arable field margins as opportunities arise.
4. Encourage the restoration and improvement of degraded arable field margins.

Where to find further information

• Buglife – advice on managing BAP habitats
• Buglife – Notable invertebrates (pdf)
• Campaign for the Farmed Environment – website
• JNCC – Habitat Description (pdf)
• MAGIC website – interactive mapping information including designations
• Making Space for Nature, a Review of England’s Wildlife Sites and Ecological Network 16 Sep 2010. Chaired by Professor Sir John Lawton CBE FRS. Defra website (pdf)
• Natural Environment White Paper June 2011 – The Natural Choice: securing the value of nature (pdf)
• RSPB – Advice for Farmers, Arable Field Margins
• Suffolk FWAG – website
• Suffolk Wildlife Trust – Habitats Explorer

* all the links marked (pdf) have been gathered into an Issuu stack

Images: 

• Field margin by Diane Ling
• Linnet by Neil Rolph (Flickr)
• Good quality arable field margin and hedge by Diane Ling
• Stag Beetle by Paul Kitchener (Flickr)