Growing oilseed rape this winter? Join a field lab to tackle flea beetle

Yesterday, farmers and researchers came together in a new field lab tackling cabbage stem flea beetle. The highlights were captured on BBC Farming Today (listen here, available until 10 January 2019)

Since 2016, Dr Sacha White and colleagues at ADAS have been researching non-chemical approaches to tackle flea beetle in a project funded by the AHDB.

How it works? 

Taking the leaves off oilseed rape in the winter through grazing or mowing exposes the larvae to the cold and predation making them much less likely to survive and damage to the plant. Plot trials at ADAS using cutting as the defoliation method has been shown to significantly reduce flea beetle infestation and increase yields. The timing is crucial as defoliation is most effective in winter, before the stem elongation phase of the crop to reduce the effect on subsequent crop growth. However, the team found that any small effects on yield are far outweighed by the reduction in pest damage towards harvest, which had up to 60% reduction in some of the plot trials.

ADAS are working with Innovative Farmers to run a field lab with oilseed rape farmers to see whether this method could work on real farms at field scale. The group are looking for more farmers to join them so if you are growing winter OSR and want to get involved please get in touch. You don’t need to commit your whole crop, a simple strip trial could give you robust results with a trial design to fit your farm. Email if you want to get involved.

Farmer's perspective

Andrew Watts, a farmer from north-east Hertfordshire, told Farming Today that he “used to grow 1000 acres of oilseed rape and now we only grow 500. In the first year the neonicotinoids were withdrawn we lost 70% of our crop. We live in a hotspot area. There’s no point in us putting on any leaf treatment, pyrethroids, because we’ve had the resistance levels checked and we’re in an area which has pretty much 100% resistance.”

Andrew Watts being interviewed on Farming Today

He sees real value in on-farm research.

“We’re always prepared to try something on a limited acreage. You can see all the trials you like but actually there’s nothing quite like trying it yourself.”

We’re looking for more farmers interested in trying different methods of defoliation - mowing or livestock grazing could be trialled depending on what works for your farm.

Join the field lab

But with winter already upon us we haven’t got long to get things moving to get that crucial timing right, so if you’re interested please get in touch. Email:, or call 0117 987 4572

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