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Bee cautious with extra sprays

Bee on oilseed rape best practice to protect bees

Spray application practices and pesticide approvals have adapted to the current moratorium on neonicotinoid seed dressings,

but best practice is required to avoid negative effects from consequent increased use of products such as pyrethroids.

In September and October, when most of these sprays are applied, there are very few bees around, apart from a few bumblebees and they are unlikely to venture into a newly sown oilseed rape crop that has no flowers in which to forage.

However, bees or other winged insects may be in field margins and hedgerows, so buffer zones and drift-reduction measures must be observed.

As part of their registration process, all pesticides must pass stringent standards on toxicity, and label guidance must be followed to avoid causing harm.

There could also be an impact on beetles and insects that will start to colonise the crop as soon as it’s planted. These include carabid beetles – important predators of slugs, which are active in the crop, particularly at night, when bees and flying insects are usually inactive.

Target species, such pollen beetle, aphids and now cabbage stem flea beetle have built up resistance to pyrethroids, encouraging wider use of neonic sprays, which have more persistence.

Tractor and sprayer over oilseed rape best practice to protect bees

Other harmful products

The formulation of fungicides, rather than the active ingredient, can also be an issue. Wetting agents dissolve and attach to lipids, which make bees less active, although they are rarely lethal.

Different flight periods can also dictate how much they are affected by sprays. Solitary or mining bees and honey bees and are most active between 10am and 4pm, particularly on warm, sunny days.

Bumblebees fly from dawn to dusk, so spraying at night is probably safest. Sprays also have a repulsive effect – they mask the smell the bees are after, so they’ll tend to avoid a recently treated field.

Most common on UK farms, honey bees are generally active between 10am and 4pm. Be aware, however, that bumblebees may still be around.

Honey bee on oilseed rape best practice to protect bees

Protecting bees

The British Bee Keepers Association (BBKA) confirms any spray application made to a flowering crop or plants that bees are visiting is likely to cause them harm, and notes this is covered by statutory guidelines.

Operators should inform bee keepers whose bees may be visiting the crops to be sprayed, giving the name of the product to be used and an approximate time period when spraying will take place. They can then decide what strategy to take to minimise the risk.

Read and adhere to label guidance carefully to understand which products are harmful and when pollinators are most at risk.

Pyrethroids are high risk because of their widespread application. Their use in flowering crops, particularly oilseed rape, peas and beans, present the greatest issues. No insecticides should be applied when bees are actively foraging in flowering crops.

Biscaya (thiacloprid) and Plenum (pymetrozine) have highly specific uses, such as for resistant pollen beetle.

Spraying for pollen beetle should take place only if threshold levels are reached, and before flowering starts – the risk of damage from the pest is over by then, and it becomes a useful pollinator.

spraying insecticide over oilseed rape best practice to protect bees

Other beneficials at risk

Spiders, beetles and many other beneficials can be affected by insecticide sprays. Getting a crop established well and fed correctly can often provide more protection against pests than applying insecticides.

Applications for bruchid beetle in beans and for pea moth are usually made in mid-flowering. Monitor before spraying, only do so if threshold levels are reached, and then take note of PGRO guidelines.

Useful links:

Pollinator management for your farm business – PDF Download HERE

Voluntary Initiative

Operation Pollinator from Syngenta



VI logo Voluntary Initiative

BeeConnected with VI

The recently introduced BeeConnected website – a project led by The Voluntary Initiative (VI) – provides an easy, interactive way to help operators inform beekeepers of their intention to spray an insecticide.

BeeConnected is designed to work quickly and efficiently for farmers and beekeepers alike.

BeeConnected operates on a very simple, yet efficient, two-way process – farmers identify their fields and, in just a few clicks, can inform local beekeepers when they intend to spray an insecticide in particular fields.

Beekeepers who plot the location of their hives will then receive a notification ahead of when a farmer within their locality is planning to undertake a spray event.

BeeConnected logo

You can log into the service here at: BeeConnected 

BeeConnected screen grab

How to protect bees:



Check for bees visiting plants. Note that honeydew produced by aphids is also attractive to bees  Spray unless you have to
Follow the environmental protection instructions on the label and the Code of Practice for using plant protection products  Use pesticides labelled ‘harmful’,      ‘dangerous’, ‘extremely dangerous’ or ‘high risk’ to bees if crops or weeds are in open flower or part bloom, unless this is allowed by the product label
Spray in the evening when bees have stopped flying, as this allows several hours for the pesticide to dry before bees become active again. Bumblebees might be around to look for food later into the evening than honey bees Mix products in the spray tank unless allowed with instructions for use of the products
Choose a cool cloudy day, or the early morning (if you must spray during the day). Let pesticide drift into bee hives or into hedgerows or fields where bees, including bumblebees, may be looking for food.



Other measures you should take:

  • In your pre-spraying environmental risk assessment assess the possible identify what precautions you should take to protect wildlife and the environment (including honey bees)
  • Check the product properties – even if the label does not specifically refer to honey bees, you should still read and carefully follow the instructions for its use
  • You are required to inform beekeepers identified in your risk assessment. If you are not aware of any beekeepers but want to make doubly sure, contact the local spray liaison officer – a list is available on the BBKA website. They can provide you with the information on beekeepers with colonies at risk
  • You should inform beekeepers 48 hours before you plan to use a pesticide at times of the year when bees are at risk or whenever you intend to use a pesticide that specifically harms bees. Tell the beekeeper(s) if you change your plans
  • Use the BeeConnected website to inform beekeepers of your intention to spray an insecticide.
Wild flower boundaries best practice to protect bees
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