Best Practice Information Sheets (Westcountry Rivers Trust)

Pest management

Best Practice
Information Sheet

Arable pest management

IS 2.6.4

Why change?

Combine cultural pest controls such as crop rotation, variety and sowing date with targeted use of chemicals for an integrated, cost-effective and long-term approach to arable pest management. Benefit from:

  • improved crop yields and quality
  • reduced risk of environmental impacts
  • reduced costs of inputs
  • increased beneficial insect populations.

Steps to success

  1. Review the current situation with your adviser by examining your management of arable pests. Consider pest problems and the success and costs of control measures across the whole of the rotation. Look at the extent to which you rely on chemical controls and the scope for balancing these with cultural techniques.
  2. Identify potential opportunities for improved management of arable pests on your farm. Consider pest populations and crop health and determine where an integrated approach to pest control could be applied. Use a BASIS-qualified agronomist for advice on integrated pest management and pesticide recommendations.
  3. Calculate the cost-benefit of these opportunities by considering the cost of any changes to your current pest management strategy versus the potential savings, e.g. reduced cost of chemical inputs.
  4. Develop an action plan for improved arable pest management on your farm:
    • consider pest management across the whole of the rotation. Identify crops at risk and apply appropriate pest management techniques. Aim to combine chemical controls with cultural measure
    • save money and protect the environment by minimising your use of chemical controls. Monitor your crops and pest levels, and base your chemical use on thresholds. Use a narrow-spectrum pesticide where possible. Avoid prophylactic treatments. Maximise your use of cultural measures
    • keep records of pest attacks and use these to anticipate future attacks
    • remove volunteers as they can serve as reservoirs of crop pests and infection sources
      if in a wheat bulb fly risk area avoid bare soil in the summer which attracts egg-laying
    • use crop rotation and crop distribution across the farm to prevent carry-over of pests
    • use pest resistant varieties where possible
    • use timely sowing to manage pests. Late sowing of autumn cereals avoids BYDV aphid vectors, whilst early sowing can encourage vigorous crop growth to withstand attack from slugs or wheat bulb fly
    • slugs can be of particular concern in low-till husbandry and on soils in wetter areas. Control measures include treatment in the previous crop, incorporation of pellets with seed at sowing, maintenance of good soil structure, pre-harvest crop desiccation, firm seedbeds, deeper sowing of cereals (4cm) and in crop treatment where monitoring indicates need. Remember that surface straw increases slug activity
    • manage the aphid vectors of BYDV by decreasing cultivations and increasing the presence of straw. Surface residues encourage predatory spiders and beetles and may prevent aphids recognising host plants by masking the recognition of newly emerged crops
    • encourage biological control by bird and insect pest predators by managing and enhancing wildlife habitats such as beetle banks, buffer zones, hedgerows and woodlands across your farm.
  1. Monitor your crops to determine treatment needs, (e.g. by forecasting, sampling or trapping), particularly during critical pest attack periods. If a problem is identified, act quickly to maintain yields and minimise costs.


Best Farming Practices: Profit from Change

Practical examples

Arable field margins

Establishing a grassy margin around arable fields will help to protect hedgerows and ditches from nutrient enrichment and from pesticide drift. These grassy margins will encourage populations of beneficial insects such as beetles and spiders which predate on crop pests.

Grassy margins will reduce overall field production and income, but these losses may be off-set by inclusion in an Environmental Stewardship Scheme. For example, a 2m naturally regenerated grassy margin will attract 300 points/ha towards the 30 points/ha required by the Entry Level Scheme, and may attract payments of up to £485/ha under the Higher Level Scheme.

You can establish the natural regeneration of grassy margins by:

  • Avoiding the use of fertilisers and manures in the margin
  • Applying herbicides only as a spot treatment of injurious weeds
  • Cutting the margins to control woody growth once every five years
  • Not using the strips for regular access, turning or storage.

Crop rotation

Use crop rotation to prevent carry-over of pests, especially nematodes. In addition, it is important to consider the pattern of cropping across your farm from one year to the next. Pests are mobile, so avoid planting vulnerable crops adjacent to the previous year's vulnerable crop.

Suggested intervals between untreated pest-susceptible crops

Pest Susceptible crops Suggested intervals

Potato cyst nematode




No PCN - 4 to 7 years

PCN infested - 6 to 13 years

Beet cyst nematode


Sugar beet, fodder beet, brassicas, oilseed rape

> 2 years for sugar beet


Stem nematode
Oats, rye, sugar beet, beans, peas, red clover

> 2 years, longer for red clover

(From Defra Arable Cropping and the Environment)



Disclaimer - Whilst the Westcountry Rivers Trust, its servants and agents (the "Trust") will use its reasonable endeavours to ensure the accuracy of its work, its advice involves matters relating to the natural environment or matters outside its reasonable control. Accordingly, other than personal injury or death arising from its negligence, the Trust will not be liable for any loss or damage howsoever arising directly or indirectly from any act, omission, neglect or default on its part. Funding for updating these information sheets was provided by the Water Quality Division of Defra as part of its England Catchment Sensitive Farming Delivery Initiative. These sheets provide practical information, guidance and recommendations for farmers based on Trust experience. © Westcountry rivers trust, 2007.

ADLib logo Content provided by the Agricultural Document Library
© University of Hertfordshire, 2011