The latest cabbage stem flea beetle stem larvae survey results should help boost confidence further for growers looking to return to UK oilseed rape.
Undertaken by Niab and funded by United Oilseeds, the survey asked 100 growers from across the UK to submit 10 OSR stems each during March. Every sample was then examined by the Niab team to determine the number of CSFB larvae present, with each participating grower receiving their own individual results.
For the second consecutive year, larval numbers have remained consistently low across the vast majority of farms surveyed. While a small number of individual sites recorded higher pressure, the national picture closely mirrors last year’s results, with significantly lower levels of CSFB than those experienced during the most challenging seasons.
Growing confidence
United Oilseeds managing director, James Warner, believes the results should give growers confidence as they begin planning for this autumn’s drilling. “Seeing low larval numbers for a second consecutive season is genuinely encouraging.
“Combined with stronger crop establishment, improving confidence and positive gross margins, the signs are there for more growers to bring OSR back into the rotation. The important thing now is that we don’t become complacent.
“By continuing to adopt practical, research-backed measures such as shallow post-harvest cultivation, we have a real opportunity to keep CSFB pressure low and continue rebuilding a resilient UK OSR crop.”
The survey findings add to a growing sense of optimism – the OSR area is increasing once again, prices have remained steady, and gross margins continue to compare favourably with many alternative break crops.
Practical measures
However, maintaining that progress depends on continuing to adopt the practical measures that have emerged through industry collaboration.
Research led by Niab has shown that carrying out a shallow cultivation of OSR stubbles to around 30mm as soon as possible after harvest, can reduce the number of emerging adult flea beetles by 50-90%. By disrupting the insects as they pupate in the soil, growers can significantly reduce the population emerging later in the summer and help lower pressure on the following crop.
As evidence has continued to build, shallow post-harvest cultivation has moved up the list of priorities within the OSR Reboot 10 Strategies for Managing CSFB. It’s now recognised as one of the most effective practical actions growers can take and remains an important area of work within the jointly funded CSFB Research+ programme, where researchers continue to refine and validate best practice.
Taking action now
However, as harvest gets underway, every grower has an opportunity to help keep CSFB pressure low ahead of this autumn’s drilling.
- Carry out a shallow cultivation of around 30 mm as soon as possible after harvesting OSR
- Watch the two videos below to see why the technique works and how to carry it out successfully
- Revisit the OSR Reboot 10 strategies for managing CSFB and consider which measures could be adopted on your farm this season
Video 1 – CSFB & soil cultivations – in the field
