Insecticides - Best Practice to Minimise the Environmental Impact in Arable Crops

The ten essentials to reduce the environmental impact of insect pest control in arable crops


  1. Know your farms potential for pest attack; field records are essential in this;
  1. Assess the implications of cropping sequences and likely attacks;
  1. Where possible, take full advantage of varietal resistance;
  1. Use cultivation techniques and sowing dates to deter attack;
  1. Use seed treatments where available if significant damage is expected;
  1. Monitor crops regularly and base management decisions on the results;
  1. Make absolutely sure a treatment is really needed; treat only when pest thresholds have been exceeded;
  1. Wherever possible, use insecticides specific to a target pest. Try especially to avoid using broad-spectrum products when the young of birds are dependent on insects for food;
  1. Apply treatments as accurately and as close to ideal timings as possible;
  1. Use buffer zones and LERAPs to protect sensitive wildlife habitats and water courses.

 

Overview



This practical leaflet offers help to farmers and advisers to reach the right decisions by giving:

1    The broad steps in an integrated approach to pest management, illustrated by a selection of examples;

2    A crop-by-crop, pest-by-pest summary of control strategies (see page 18).

 

Introduction


Insects and other pests have the potential to be extremely damaging to arable crops and insecticides, molluscicides and nematicides will remain an option for controlling them for the foreseeable future.

However insects, slugs and other pests are an important part of the natural ecosystem. Insects are the major pollinators for many flowering species of plants, including crops, and an integral part of the food chain, especially for a number of declining farmland birds and for small mammals.

There is, therefore, a need to strike a sensible balance which continues to ensure healthy, profitable crops while at the same time helping wildlife to thrive within and around the cropped area. Indeed, many valuable beneficial insects help to control pests such as aphids within our crops, reducing the need to spray.

However, modern crop management has altered the natural balance with its swing towards autumn drilling, block cropping, greater use of nitrogen fertilisers, the introduction of pesticides and the loss of  livestock in the rotation. It is estimated that, as a result, there has been a 75% reduction in the numbers of insects found in arable fields since the 1950s.

Integrated Pest Management (IPM), the crop protection element within Integrated Crop Management (ICM), aims to redress the balance. Within IPM, many factors are crucial in helping to sustain healthy biodiversity on farmland, such as the preparation of the field, crop rotation and varietal choice right through to monitoring pest numbers and deciding whether an insecticide treatment is needed or not.

Much of its success depends on careful forward planning so that pest problems are minimised before the crop is even planted, thus reducing the need to use chemical crop protection. All control options need to be considered, depending on the range of pests which are important in a locality, the soil type and the crops being grown in the rotation. Despite best endeavours, however, a pest can still reach damaging levels and the same careful thought needs to go into the appropriate choice and use of the wide range of chemical products available.

Agronomic experience is paramount in IPM but so is an awareness of the potential threats to wildlife of any pest control action.

 

Integrated Pest Management

The four foundations

1   Identify sensitive areas and what you are trying to protect
watercourses, hedges, woodland, field margins, farmland birds etc

2   Plan to prevent and avoid pest problems (pages 6 to 9)
rotations, hygiene, varieties, cultivations, drilling dates, seed treatments, conservation headlands, beetle banks, farm records etc

3   Evaluate the risk and the need to control (pages 10 to 13)
location, field history, forecasting, monitoring, thresholds etc

4   Apply insecticides safely (pages 14 to 16)
product choice, application techniques, preventative spraying, timing, rates, protecting bees, headlands, water

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