Article taken from the Farmers Guardian
Slugs and flea beetles are causing widespread damage in slow-growing oilseed rape crops on heavier soils in northern England. Close monitoring will be needed to help crops through vulnerable early growth stages, growers are being advised.
Agrovista technical manager Chris Martin says: “Slugs are really having a go in crops that were drilled into dry, cobbly seedbeds.”
An application of good qualifty metaldehyde pellets works well in drier conditions, he adds. Ferric phosphate should be used for further applications to keep within the metaldehyde stewardship guideline (maximum of 210g metaldehyde/ha from August to December), advice which will also hold good for cereals going into less-than-ideal seedbeds.
Flea beetle
Flea beetle shot-holing is pretty severe in many oilseed rape crops. “We are now seeing the first evidence of the loss of neonicotinoid seed treatments,” says North Yorkshire-based Mr Martin.
Thresholds suggest spraying a pyrethroid is 25 per cent of leaf area is eaten between cotyledon and two true leaves, and 50 per cent from 204 true leaves, or any time if the crop is going backwards. “Pyrethroids do not last long so keep checking for damage,” he adds.
Oilseed rape growers in Lancashire, Cheshire and North Wales are having an easier time, according to Agrovista agronomist Phil Campion, who looks after crops in the region.
He says: “Crops were drilled early into good seedbeds with moisture and they were all hybrids which helped them get away.” However, cereal volunteers are also growing rapidly and spraying has begun to prevent them competing,” he says.
Maize is ripening rapidly, adds Mr Campion. “We have had some phenomenal growth this year. The weather has been ideal and most crops will be ready by the end of September.”
OSR pests
Cabbage stem flea beetle and slugs causing widespread damage:
Slugs and flea beetles are causing widespread damage in slow-growing oilseed rape crops on heavier soils in northern England. Close monitoring will be needed to help crops through vulnerable early growth stages, growers are being advised.
Agrovista technical manager Chris Martin says: “Slugs are really having a go in crops that were drilled into dry, cobbly seedbeds.”
An application of good qualifty metaldehyde pellets works well in drier conditions, he adds. Ferric phosphate should be used for further applications to keep within the metaldehyde stewardship guideline (maximum of 210g metaldehyde/ha from August to December), advice which will also hold good for cereals going into less-than-ideal seedbeds.
Flea beetle
Flea beetle shot-holing is pretty severe in many oilseed rape crops. “We are now seeing the first evidence of the loss of neonicotinoid seed treatments,” says North Yorkshire-based Mr Martin.
Thresholds suggest spraying a pyrethroid is 25 per cent of leaf area is eaten between cotyledon and two true leaves, and 50 per cent from 204 true leaves, or any time if the crop is going backwards. “Pyrethroids do not last long so keep checking for damage,” he adds.
Oilseed rape growers in Lancashire, Cheshire and North Wales are having an easier time, according to Agrovista agronomist Phil Campion, who looks after crops in the region.
He says: “Crops were drilled early into good seedbeds with moisture and they were all hybrids which helped them get away.” However, cereal volunteers are also growing rapidly and spraying has begun to prevent them competing,” he says.
Maize is ripening rapidly, adds Mr Campion. “We have had some phenomenal growth this year. The weather has been ideal and most crops will be ready by the end of September.”
OSR pests
Cabbage stem flea beetle and slugs causing widespread damage:
Close monitoring needed to help crops through early growth stages
Application of good quality metaldehyde slug pellets works well in drier conditions
Use ferric phosphate for further applications to keep within metaldehyde use guidelines
Flea beetle shotholing severe in many OSR crops