‘Magic’ technology helps farmers fight CSFB

Cabbage stem flea beetle (CSFB) was not much in evidence in the two MagicTraps deployed at Overbury Enterprises last autumn. Trap counts were low in what was generally a low-pressure season for the oilseed rape pest in most regions, Bayer Crop Science explained. 

Farms manager Jake Freestone was using Bayer’s digital yellow water traps for the first time, installing one in low-lying vale land at around 100ft above sea level and a second on higher hill land at 850ft. 

He said that the aim was to monitor how the traps, which were part of the United Oilseeds MagicTrap network, performed at different topographies, on different soil types and in different areas of the farm, which sits on the Herefordshire/Worcestershire border. 

CSFB has been a sporadic problem at Overbury since the ban on use of neonicotinoid seed treatments in oilseed rape in 2013. Yet, despite the CSFB challenge, oilseed rape has retained its place in the rotation on the farm, although the area has dropped in recent seasons. 

Mr Freestone said: “We’re combining about 900 hectares [of arable crops] here and another couple of hundred hectares next door, and probably 200 hectares would traditionally have been rapeseed. 

“I have persevered with it, although for one reason and another the area had slipped back a little this year, but that was mainly down to rotation, and we’re due to go back up again this year.”

‘Cultural methods’ in use

With agronomy based on an IPM/ICM approach, a key aim is to avoid using synthetic insecticides where possible. 

“We haven’t used insecticides on the farm since 2018. We use a lot of cultural methods to try and avoid using them,” Mr Freestone added. 

Land going into oilseed rape receives an application of poultry litter after the crop has been direct drilled into chopped straw and a decent stubble.  

The farms manager added: “We also put companion crops in with the rape; we’re trying to do everything we can without reaching for an insecticide. 

“We did once send some flea beetle off to be tested, and they came back at 77% resistant to pyrethroid insecticides, so there’s probably no point in spraying anyway.” 

Other measures include growing hybrid OSR varieties – typically from the Bayer DEKALB portfolio – to take advantage of their spring vigour and potential ability to grow away from CSFB stem larvae. 

Last season’s newcomer DK Excentric is in the variety line-up, alongside Dolphin, for harvest 2025 and is looking well on the higher land, Mr Freestone added. 

A shift in OSR drilling date has also been introduced as part of the farm’s approach to managing flea beetle. 

“We have started drilling very early, in the first week of August, to try and get the OSR up and a leaf established before the main flea beetle migration at the end of August. 

“We had pretty good establishment last autumn, and flea beetle weren’t really an issue. We did have some winter stem larval damage, but the crops seemed to grow through that,” he continued. 

MagicTraps

Mr Freestone initially placed the MagicTraps in fields with rape stubble and a cover crop, before moving them into new season crops three weeks after drilling. 

“My aim was firstly to get used to the technology and secondly, to have a look at what was emerging from previous oilseed rape fields to try and get a gauge on cabbage stem flea pressure, but there wasn’t really very much pressure at all,” he said. 

Setting up and using the two MagicTraps was straightforward, although one consideration was dealing with a patchy mobile phone signal. 

“I was trying to find a place in the field where I thought the beetle was likely to land, so in the field margins, but also somewhere we could get a signal.  

“I found I’d get a signal one day, and then the next day the signal had disappeared. That’s not a particular issue with MagicTrap, it’s a rural issue across the board.” 

With no insecticides applied on the farm he is not using MagicTrap to inform spraying decisions; instead, the benefit comes in the form of saving time on crop walking. 

“It also gives me a nice record of what is happening with flea beetle. The fact that MagicTrap is recording a digital footprint means that over time we will hopefully be able to build up a picture of what sort of populations we have, in what fields and in what kind of weather kind of conditions,” the expert continued.

Generating robust data  

Following the successful rollout of the United Oilseeds MagicTrap network last year, the aim is to continue to build on the current 48-trap network, said Peter Collier, UOM area manager for the East Anglia region.  

“Last year we learnt a lot around what works best in terms of MagicTrap field positioning, timing and best practice. Now we’ve got many more traps in our network and being shared with us, there is a lot more coverage, and we can be increasingly scientific in our approach. 

“In order to get a metric of cabbage stem flea beetle, pollen beetles and weevil numbers, we want consistent placing of traps within a field. We’ve been standardising our approach across the MagicTrap network to achieve that.   

“A single trap on its own provides good information for that farm, but with a consistent way of doing things, then on aggregate, the data is more meaningful for a national picture, and good data in enables good data out,” he concluded. 

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