A number of technical sessions at the recent CAFRE/UAS/UFU arable conference provided useful information and advice to farmers. Subjects such as our chemical registration system, using IPM to help control brome grasses and revised UK fertiliser recommendations were discussed.
RB209 is the Fertiliser Manual for UK growers. It is the equivalent of the Green Book here and it provides fertiliser use advice for crops and soil types across the UK. This has recently been reviewed.
At the CAFRE conference Dr Pete Berry from ADAS outlined the main N application rate changes. These provide for an additional 20kgN/ha to be applied on winter wheat on light sand at most soil nitrogen supply (SNS) indices, except for Index 6. This now provides for a maximum of 180kgN/ha at Index 0 with 30kg/ha less for each subsequent index.
Maximum application rates for deep silt soils have also been increased by 20kgN/ha on Index 0, 1 and 2 soils. There is no rate change for spring wheat.
Rates on winter barley for feed grain have also been increased by 10-20 kgN/ha on light sands and silts at all soil index levels and on shallow soils at SNS Index 0. Changes were also made to N use levels on winter and spring barley to produce target grain N levels for malting. N rates for spring feed barley have been increased by 20-30 kgN/ha for light sands.
The biggest change was in oats, where N rates were increased by 40kgN/ha. Rates on triticale were also increased and are now the same as winter wheat.
N rates were also adjusted for yield potential. Rates can now be adjusted up or down by 20kgN/ha for every t/ha of grain produced either side of:
8t/ha for winter wheat.
6.5t/ha for feed winter barley.
5.5t/ha for feed spring barley.
The oilseed rape rate yield adjustment remains the same at 30kgN/ha for every 0.5t/ha of seed yield above 3.5t/ha.
A new provision allows for the rebuilding of low soil P and K indices in five to 10 years on Index 0 and Index 1 soils. This allows for an additional 100kg/ha on Index 0 soil or an additional 50kg/ha on Index 1 soils. These rates are for P2O5 and K2O and equate to 43.5 (Index 0) or 21.75 (Index 1) kgP/ha and 83 (Index 0) or 41.5 (Index 1) kgK/ha.
Putting the brakes on brome
“We need to alter our general approach to weed control, get away from total reliance on herbicides and look more towards an integrated management approach.”
These were the comments of CAFRE’s crops development adviser, Leigh McClean. He referenced brome control in particular and the increasing menace that this weed is posing for producers.
All farmers are experiencing an increasing challenge from weed control and asking why this is. Leigh suggested:
Lack of rotation.Intensity of rainfall events in recent years.Cold springs that favour weeds over the crop.The evolution of resistance.Increasing opportunities for weeds to spread.Integrated crop management means doing things that disadvantage the weed while favouring the crop. But with any weed, prevention is easier and cheaper than cure and this must remain the primary focus of farmers.
Weed prevention
In terms of weed prevention, Leigh posed these questions in respect of any weed.
Where can it come from?How can it be spread on the farm?How can it carry onto next year’s crops?These basic questions apply to all weeds and pests and every problem needs to be tackled on all three fronts. Talking specifically about brome grasses, Leigh said that zero tolerance is the best policy. He said it is important to know the difference between the species as appropriate action varies with species.
Cultural controls are important with brome grasses. Problems are most associated with hedges and edges, ploughing ins-and-outs and parts of fields where good plough burial does not occur. Hand rogueing and mechanical weeding help but sterile brome is very difficult to rogue successfully. Spot spraying could be very useful, even by knapsack sprayer, because it’s all about preventing seed return.
Ditches
Spraying off the butts of ditches with glyphosate provided the initial entry point in many fields. It then proliferated in the hedges and spread out into the fields. The reason it is worst by the hedge is because one does not get clean burial with the last run of the plough when turning the ploughing towards the field. Obstacles like poles, etc, also provide a multiplication opportunity but generally brome is less likely to establish where other vegetation is present.
Where a problem exists, Leigh suggested a number of actions to help contain and eliminate it. Very bad areas will pull down the crop – such areas could be mulched, whole cropped or sprayed off before seed set. Examples might be around by headlands and ins-and-outs or specific patches.
Other control options include stale seedbeds, crop type and spring or winter planting. Delayed drilling is less favourable for most grass weeds, as is spring planting. Putting a field down to grass for one to two years is perhaps the best single action for control. Leigh said that one might expect a 90% reduction in sterile brome numbers following a one year ley but that this would push towards 100% after 18 months or so.
Some additional comments on IPM and brome. The main problem is sterile brome and this can be eliminated culturally. Think in terms of seed return – this must be prevented.
Consider ploughing the headlands into the hedge for two consecutive years to secure good seed burial on this critical run. Alternatively put in a 3-4m strip of grass along by hedges or banks and top to prevent seeds being set. A year or two of no seed return will hopefully end the problem.
As for the ins-and-outs, move this line in or out 3-4m depending on the size of your plough and drill. If you can bury the seeds cleanly where the problem exists it will quickly diminish.
Patches where the plough can’t turn the sods are more difficult. These may have to be burned off for a few consecutive years. But a few years of no plough should make it tight enough to turn cleanly in time. In the field itself you should consider not ploughing for at least a year. It makes little sense to plough down brome only to turn it up again a year later. Using good ploughing, try to leave the problem buried for 2-3 years to help reduce. Always cultivate post harvest to get seeds to strike. If you have a mixture of species, or only sterile brome, cultivate asap. This must be shallow – as close to 5cm as is possible. Once you see a green hue tickle it again to kill these and get other seeds to grow. This also helps with other grass weeds like wild oats and broadleaved weeds.
Agchem registration
Tillage farmers are increasingly aware of the pressures that exist on active substance availability for plant protection in the EU. At the Greenmount conference many growers may well have wondered if this might be altered in a post-Brexit UK. While that answer remains uncertain, Louise Brinkworth from Dow AgroSciences explained the evolution of the EU registration system.
Prior to 1993, each country in the EEC operated its own rules for agrochemical registration. Since then the registration regulations were harmonised across member states with registration and reregistration of active substances done by one member state while commercial products had to be registered by each member state.
The next major change came in 2011 with the introduction of EC 110/2009. This introduced many changes such as the sustainable use directive, which required adviser and operator registration and sprayer testing. But its most profound change centred around the precautionary principle. This replaced risk as an evaluation criterion with hazard and this introduced new assessment criteria.
Louise explained the difference between risk and hazard using two little images. One showed a person standing on a quayside looking out into water where sharks were swimming - a risk or potential hazard. The second showed a person swimming in the water with the sharks – a definite hazard because the sharks now had access to the person.
In the late 1990s, there were about 870 active substances registered for use in the EU. This dropped to just under 250 by 2003 and this number remains broadly similar today. And almost half this current number are relatively new actives, so others continue to be lost.
Louise said that the precautionary principle also ranked substances in terms of their total profile and introduced a concept called comparative assessment. The use of an active that was less favoured for the environment was to be discouraged and it was to be replaced by something more benign. Currently 77 products are listed as candidates for substitution and roughly 44 of these are considered as being of relevance to these parts.
While pesticide legislation controls chemical registration, Louise said that many other regulations also impinge. Things like the water framework directive, sustainability, residue regulations, etc, are all relevant to the decision-making process. And some member states have specific regulations, such as Denmark. Louise emphasised that the central and national elements of our registration process are very rigorous and subject to a lot of independent scrutiny.
She also said that the EU registration process takes a long time and that this affects the return on investment for the manufacturer as it eats up patent protection. In 1985 it took 8.3 years to get a new active to market. Now this takes 11.3 years. And the cost of production has increased from $152m in 1995 to an estimated $286m per product today.
While there are many more chemical molecules being synthesised nowadays, the number of new actives in development has decreased. In 1995 it took around 52,000 molecules to get four to development stage and one registered. Nowadays it takes three times that number of new molecules to get one active registered.
In short
Nitrogen rates in the UK have been increased for lighter soils and some crops. Rates can now also be adjusted for expected output levels. It is unrealistic to think that we can get the better of many of our weed problems without the use of integrated crop management and cultural practices.The number of registered actives available to EU farmers has decreased from 870 to around 250 in the past 20 years.
A number of technical sessions at the recent CAFRE/UAS/UFU arable conference provided useful information and advice to farmers. Subjects such as our chemical registration system, using IPM to help control brome grasses and revised UK fertiliser recommendations were discussed.
RB209 is the Fertiliser Manual for UK growers. It is the equivalent of the Green Book here and it provides fertiliser use advice for crops and soil types across the UK. This has recently been reviewed.
At the CAFRE conference Dr Pete Berry from ADAS outlined the main N application rate changes. These provide for an additional 20kgN/ha to be applied on winter wheat on light sand at most soil nitrogen supply (SNS) indices, except for Index 6. This now provides for a maximum of 180kgN/ha at Index 0 with 30kg/ha less for each subsequent index.
Maximum application rates for deep silt soils have also been increased by 20kgN/ha on Index 0, 1 and 2 soils. There is no rate change for spring wheat.
Rates on winter barley for feed grain have also been increased by 10-20 kgN/ha on light sands and silts at all soil index levels and on shallow soils at SNS Index 0. Changes were also made to N use levels on winter and spring barley to produce target grain N levels for malting. N rates for spring feed barley have been increased by 20-30 kgN/ha for light sands.
The biggest change was in oats, where N rates were increased by 40kgN/ha. Rates on triticale were also increased and are now the same as winter wheat.
N rates were also adjusted for yield potential. Rates can now be adjusted up or down by 20kgN/ha for every t/ha of grain produced either side of:
8t/ha for winter wheat.
6.5t/ha for feed winter barley.
5.5t/ha for feed spring barley.
The oilseed rape rate yield adjustment remains the same at 30kgN/ha for every 0.5t/ha of seed yield above 3.5t/ha.
A new provision allows for the rebuilding of low soil P and K indices in five to 10 years on Index 0 and Index 1 soils. This allows for an additional 100kg/ha on Index 0 soil or an additional 50kg/ha on Index 1 soils. These rates are for P2O5 and K2O and equate to 43.5 (Index 0) or 21.75 (Index 1) kgP/ha and 83 (Index 0) or 41.5 (Index 1) kgK/ha.
Putting the brakes on brome
“We need to alter our general approach to weed control, get away from total reliance on herbicides and look more towards an integrated management approach.”
These were the comments of CAFRE’s crops development adviser, Leigh McClean. He referenced brome control in particular and the increasing menace that this weed is posing for producers.
All farmers are experiencing an increasing challenge from weed control and asking why this is. Leigh suggested:
Lack of rotation.Intensity of rainfall events in recent years.Cold springs that favour weeds over the crop.The evolution of resistance.Increasing opportunities for weeds to spread.Integrated crop management means doing things that disadvantage the weed while favouring the crop. But with any weed, prevention is easier and cheaper than cure and this must remain the primary focus of farmers.
Weed prevention
In terms of weed prevention, Leigh posed these questions in respect of any weed.
Where can it come from?How can it be spread on the farm?How can it carry onto next year’s crops?These basic questions apply to all weeds and pests and every problem needs to be tackled on all three fronts. Talking specifically about brome grasses, Leigh said that zero tolerance is the best policy. He said it is important to know the difference between the species as appropriate action varies with species.
Cultural controls are important with brome grasses. Problems are most associated with hedges and edges, ploughing ins-and-outs and parts of fields where good plough burial does not occur. Hand rogueing and mechanical weeding help but sterile brome is very difficult to rogue successfully. Spot spraying could be very useful, even by knapsack sprayer, because it’s all about preventing seed return.
Ditches
Spraying off the butts of ditches with glyphosate provided the initial entry point in many fields. It then proliferated in the hedges and spread out into the fields. The reason it is worst by the hedge is because one does not get clean burial with the last run of the plough when turning the ploughing towards the field. Obstacles like poles, etc, also provide a multiplication opportunity but generally brome is less likely to establish where other vegetation is present.
Where a problem exists, Leigh suggested a number of actions to help contain and eliminate it. Very bad areas will pull down the crop – such areas could be mulched, whole cropped or sprayed off before seed set. Examples might be around by headlands and ins-and-outs or specific patches.
Other control options include stale seedbeds, crop type and spring or winter planting. Delayed drilling is less favourable for most grass weeds, as is spring planting. Putting a field down to grass for one to two years is perhaps the best single action for control. Leigh said that one might expect a 90% reduction in sterile brome numbers following a one year ley but that this would push towards 100% after 18 months or so.
Some additional comments on IPM and brome. The main problem is sterile brome and this can be eliminated culturally. Think in terms of seed return – this must be prevented.
Consider ploughing the headlands into the hedge for two consecutive years to secure good seed burial on this critical run. Alternatively put in a 3-4m strip of grass along by hedges or banks and top to prevent seeds being set. A year or two of no seed return will hopefully end the problem.
As for the ins-and-outs, move this line in or out 3-4m depending on the size of your plough and drill. If you can bury the seeds cleanly where the problem exists it will quickly diminish.
Patches where the plough can’t turn the sods are more difficult. These may have to be burned off for a few consecutive years. But a few years of no plough should make it tight enough to turn cleanly in time. In the field itself you should consider not ploughing for at least a year. It makes little sense to plough down brome only to turn it up again a year later. Using good ploughing, try to leave the problem buried for 2-3 years to help reduce. Always cultivate post harvest to get seeds to strike. If you have a mixture of species, or only sterile brome, cultivate asap. This must be shallow – as close to 5cm as is possible. Once you see a green hue tickle it again to kill these and get other seeds to grow. This also helps with other grass weeds like wild oats and broadleaved weeds.
Agchem registration
Tillage farmers are increasingly aware of the pressures that exist on active substance availability for plant protection in the EU. At the Greenmount conference many growers may well have wondered if this might be altered in a post-Brexit UK. While that answer remains uncertain, Louise Brinkworth from Dow AgroSciences explained the evolution of the EU registration system.
Prior to 1993, each country in the EEC operated its own rules for agrochemical registration. Since then the registration regulations were harmonised across member states with registration and reregistration of active substances done by one member state while commercial products had to be registered by each member state.
The next major change came in 2011 with the introduction of EC 110/2009. This introduced many changes such as the sustainable use directive, which required adviser and operator registration and sprayer testing. But its most profound change centred around the precautionary principle. This replaced risk as an evaluation criterion with hazard and this introduced new assessment criteria.
Louise explained the difference between risk and hazard using two little images. One showed a person standing on a quayside looking out into water where sharks were swimming - a risk or potential hazard. The second showed a person swimming in the water with the sharks – a definite hazard because the sharks now had access to the person.
In the late 1990s, there were about 870 active substances registered for use in the EU. This dropped to just under 250 by 2003 and this number remains broadly similar today. And almost half this current number are relatively new actives, so others continue to be lost.
Louise said that the precautionary principle also ranked substances in terms of their total profile and introduced a concept called comparative assessment. The use of an active that was less favoured for the environment was to be discouraged and it was to be replaced by something more benign. Currently 77 products are listed as candidates for substitution and roughly 44 of these are considered as being of relevance to these parts.
While pesticide legislation controls chemical registration, Louise said that many other regulations also impinge. Things like the water framework directive, sustainability, residue regulations, etc, are all relevant to the decision-making process. And some member states have specific regulations, such as Denmark. Louise emphasised that the central and national elements of our registration process are very rigorous and subject to a lot of independent scrutiny.
She also said that the EU registration process takes a long time and that this affects the return on investment for the manufacturer as it eats up patent protection. In 1985 it took 8.3 years to get a new active to market. Now this takes 11.3 years. And the cost of production has increased from $152m in 1995 to an estimated $286m per product today.
While there are many more chemical molecules being synthesised nowadays, the number of new actives in development has decreased. In 1995 it took around 52,000 molecules to get four to development stage and one registered. Nowadays it takes three times that number of new molecules to get one active registered.
In short
Nitrogen rates in the UK have been increased for lighter soils and some crops. Rates can now also be adjusted for expected output levels. It is unrealistic to think that we can get the better of many of our weed problems without the use of integrated crop management and cultural practices.The number of registered actives available to EU farmers has decreased from 870 to around 250 in the past 20 years. 
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