concentrations, might be taken up by flowering plants in untreated habitats. However, we may have to accept that the modern countryside is a hazardous place, especially if a new generation of insecticides ends up replacing neonicotinoids

The fact is that the risk to pollinators must be reduced as much as possible to below sub-lethal levels and the advantages of the provision of ‘refuges’ outweigh the risks of establishing them. In some circumstances pesticides have allowed habitats to survive. For example, Natural England sanctioned use of glyphosate to enable one of England’s largest areas of wild cornflowers to bloom.

Some might believe that the word ‘refuges’ implies guilt that insecticides are harmful to the environment. But it must be braver for us to seek to improve, champion and challenge better practices that enable us to farm more effectively and efficiently while also respecting nature by giving it more chances to thrive alongside our own needs. C

More informationThis is an edited version of Rob Yorke’s opinion piece for www.farmingfutures.org.uk Farming Futures blogs information and opinions to help farmers and land managers make strategic decisions about the future shape of their businesses Twitter.com/FarmingFutures

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Rob Yorke FRICS is a Rural Chartered Surveyor and commentatorry@robyorke.plus.com, twitter.com/blackgull

Rob Yorke offers his view on how to release tension between the agricultural benefits of some modern pesticides and their environmental impacts

TPesticides versus pollinators

may increase crop damage directly from insects and the viruses spread by them.

Insecticides have come a long way from the days of Rachel Carson’s 1962 book Silent spring, which documented the detrimental effect of pesticides on the environment. Since then, the indiscriminate use of synthetic agro-chemicals has been replaced by the application of more complex compounds involving precise application during optimum weather conditions, which, in theory, reduces the negative impact on the environment to a minimum.

Neonicotinoids, currently the most common type of insecticide, are applied as a water soluble seed dressing, which is systemically taken up by the plant within its vascular system. However, the efficiency of absorption by the plant – the active chemical appears in pollen and nectar of flowers – has been offset by concern about its possible persistence within the environment and organisms (bio-accumulation).

Could the ban have unexpected consequences for

pollinators? Some argue that heavier doses of ‘less effective’ pesticides may affect a wider range and number of non-target insects. Farmers may also decide to reduce the area of OSR grown, which, in turn, removes valuable foraging to ‘managed’ honey bees and some wild pollinators.

By banning insecticides, are we sidestepping a greater cause of pollinator decline – habitat loss?

Even allowing for the attraction of mass flowering crops such as OSR, the reduction in habitat reduces options for pollinators – not just bees, but also flies and hoverflies – to forage anywhere other than within chemically treated crops. This, potentially, has chronic effects on the health of pollinators vital to both wild flowers and crops.

RefugesOne answer could be the planting of specific habitat (referred to as ‘refuges’) as part of granting licences to use certain insecticides. Enforcing the sowing and maintenance of pollinator-attractive wild flowers or grasses close to the treated crop creates, in effect, ‘spare’ land for efficient agro-chemical treated food production, while ‘sharing’ the less-treated ‘refuge’ habitat with biodiversity.

The ‘refuge’ habitat itself might not be without hazard. Research on the persistence of neonicotinoids demonstrates that they may move laterally in the soil and although at lower

The European Union has temporarily banned the use of some neonicotinoid chemicals on flowering crops, such as oil seed rape (OSR), because of fears over their effect on pollinators. The UK government has accepted the ban but disputes the science behind it.

There is no argument that insecticides such as neonicotinoids and pyrethoids, kill insects. They are designed to do so in different ways, with differing efficiency and doses.

Agricultural ecosystems, which cover 75% of the UK countryside, have been highly manipulated and are full of ‘hard choice’ trade-offs and unexpected consequences. In the future, there is every chance that climate change

Related competencies include Agriculture, Management of the natural environment and landscape

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Image © Andrew Mills, Natural England