gavin
27-02-2014, 09:31 AM
The Crop Protection in Northern Britain conference in Dundee over the last two days had lots of interesting stuff on potatoes, combinable crops, and various issues to do with crops but also three papers of relevance to one hot topic of the moment, the two or more year moratorium on neonicotinoid seed dressings on OSR.
The first was an explanation of the various pesticides used over the years on OSR and how the areas treated have changed over time (generally in an upwards direction). Now 94% of OSR in Scotland is from seeds dressed with neonics and 70% also gets a foliar insecticide, a much higher rate than cereals for example. The two year (at least) moratorium will mean that farmers will turn to additional sprays in an effort to control the young plant pests flea beetle (leaf damage on young plants), cabbage stem weevil (tunnelled stems weaken) and cabbage aphids (which transmit virus). There are some spray treatments available, but uncertainty as to how effective they will be and whether farmers will always be able to drive over the fields to spray when needed.
One I missed, but had reported to me, was from an independent and respected consultant in England who has compared the establishment of neonic-dressed and non-dressed OSR. Terrible problems with untreated seed, so it is not just the agrochemical companies who say this but others too believe that a proportion of rape growing is just not going to be economic any more. Rape crops are likely to decline significantly (both in area and their performance where they are grown), and so pollinators are likely to suffer from reduced forage. One of the unintended (but predictable) effects of a ban/moratorium. Only time will tell what will really happen, but there are signs already that rape cropping may decline.
Finally the first results of two years of random honeybee health surveys by the Scottish Government were presented. The first year had low winter losses (11%), the second high (31%). These are from memory and align quite well with what we've seen locally. Various additional data had been collected and the clearest pattern was a strong correlation between the summer Varroa count in an apiary and the subsequent winter loss. Interestingly, the beekeepers involved were invited to comment on what they thought caused their winter losses and pesticides just didn't feature. Beekeepers themselves were pointing the finger at queen issues, Varroa, starvation, small colonies, all the usual things.
G.
The first was an explanation of the various pesticides used over the years on OSR and how the areas treated have changed over time (generally in an upwards direction). Now 94% of OSR in Scotland is from seeds dressed with neonics and 70% also gets a foliar insecticide, a much higher rate than cereals for example. The two year (at least) moratorium will mean that farmers will turn to additional sprays in an effort to control the young plant pests flea beetle (leaf damage on young plants), cabbage stem weevil (tunnelled stems weaken) and cabbage aphids (which transmit virus). There are some spray treatments available, but uncertainty as to how effective they will be and whether farmers will always be able to drive over the fields to spray when needed.
One I missed, but had reported to me, was from an independent and respected consultant in England who has compared the establishment of neonic-dressed and non-dressed OSR. Terrible problems with untreated seed, so it is not just the agrochemical companies who say this but others too believe that a proportion of rape growing is just not going to be economic any more. Rape crops are likely to decline significantly (both in area and their performance where they are grown), and so pollinators are likely to suffer from reduced forage. One of the unintended (but predictable) effects of a ban/moratorium. Only time will tell what will really happen, but there are signs already that rape cropping may decline.
Finally the first results of two years of random honeybee health surveys by the Scottish Government were presented. The first year had low winter losses (11%), the second high (31%). These are from memory and align quite well with what we've seen locally. Various additional data had been collected and the clearest pattern was a strong correlation between the summer Varroa count in an apiary and the subsequent winter loss. Interestingly, the beekeepers involved were invited to comment on what they thought caused their winter losses and pesticides just didn't feature. Beekeepers themselves were pointing the finger at queen issues, Varroa, starvation, small colonies, all the usual things.
G.