With more winter cereals set to go into the ground this autumn, staying on top of troublesome weeds is increasingly important.
Many modern grassweed herbicides utilise actives that are best applied pre-emerge and that means being organised to move during planting, or shortly afterwards. It is also increasingly difficult to achieve full control of grass and broadleaved weeds with a single treatment. This means that sequences must be planned, especially for awkward grassweeds. Herbicide resistance adds a further complication.
All of these changes mean that pre-emerge options should be targeted, where possible. There are reasonable grassweed products available for use post-emergence in wheat, but this is more challenging in barley.
Wheat
There are numerous products that can be used pre- or post-emergence on wheat, but many work better pre-emerge, providing seedbed conditions are suitable. The main actives used for grass and broadleaved weed control are those containing flufenacet and diflufenican (DFF). These products can also be applied post-emerge.
These actives are found in products such as Firebird, Navigate, Griffen, Reliance and Naceto. Different products have different application rates and they vary in the number of treatments allowed. So, check the label before use. Rates also differ for wheat and barley.
Both actives are also available as single ingredients. Diflufenican is available as Diflanil, Hurricane, Stride and FarmCo Dazzle (plus others). Straight flufenacet is available as Fence, Glosset, and Clayton Tacit. Again, check the label, because rates differ.
Another commonly used active is pendimethalin (PDM). This can be bought alone as products such as Stomp Aqua or Most Micro, in combination with DFF in products like Bulldog and Adept, or with picolinafen as Flight.
Another active for use in combinations is prosulfocarb. This is contained in products like Defy, Crozier and Roxy 800C. These are generally applied pre-emerge, but rate and application details differ, eg Defy. Prosulfocarb is also sold in a mix with DFF as Purelo.
Monolith is a post-emergence option for use on wheat, rye, and triticale. It is particularly strong on grassweeds and is used to target sterile brome, blackgrass, wild oats and meadowgrasses. It can be used up to GS33, but earlier application is preferable.
Broadway Star is used as part of a programme to tackle sterile brome in particular. However, it needs to have PDM applied in advance to tackle annual meadowgrass. It should be used in early spring with an adjuvant.
Barley
Control of certain grassweeds, such as sterile brome in winter barley, is particularly difficult due to the lack of chemistry.
Products containing flufenacet, which include Firebird, Navigate, Griffen and Reliance, have good residual control on grass weeds, especially annual meadow grass, and are also good on broadleaved weeds. Rates vary between individual products, however.
Prosulfocarb, ie Defy, is a very good option for high annual meadowgrass situations – but avoid use at pre-emerge on winter barley. Add DFF for additional broadleaved weed control. Pendimethalin-based products – Stomp Aqua, Most Micro (various rates) etc – have good residual activity for pre-emerge situations and are good on annual meadowgrass. Generally better on fumitory than DFF, but weak on groundsel.Tower, which contains chlorotoluron, PDM and DFF, is good on annual meadowgrass plus broadleaved weeds. A 9m buffer zone is required along water courses. Baraca Triple at 0.7l/ha is good on annual meadow grass and a range of broadleaved weeds as an early post-emerge. Avadex Factor, which contains tri-allate, targets grass and other weeds pre-emerge as part of a program.Diflufenican, ie Diflanil 500, Hurricane and Stride, is useful against a range of broadleaved weeds. It is poor on fumitory and poppy, however. Pendimethalin plus picolinafen ie Flight, is good on cleavers, poppy and fumitory, but is weak on groundsel. Use pre-emerge for best annual meadowgrass control. Pendimethalin and DFF mixes, such as Adept or Bulldog, control a broad spectrum of broadleaved weeds. Adjust rates for post-emerge. Fence or Flosset, containing flufenacet, at 0.5l/ha or 0.4l/ha respectively, are good on grass weed control when used early and is generally a tank mix partner for DFF and PDM mixes. Three-way mixes
Three-way mixes include Bacara Triple and Tower. These can be applied pre- or early post-emergence. Bacara Triple is a mix of flufenacet, DFF and metribuzin, while Tower is a mix of PDM, chlorotoluron and DFF. Bacara Triple can be applied up to GS13, but Tower can be applied up to GS30.
Programmed approach
With resistance being an ever-increasing issue, the re-introduction of Avadex Factor for pre-emerge on winter wheat provides another option for control of blackgrass, sterile brome and other serious grass problems.
It can be applied with flufenacet +/- DFF or PDM. It must always be used as part of a programme. A follow up treatment will always be required.
Post-emerge or tidy-up sprays
There are many other herbicides that can be used to tidy up problem weeds that escaped autumn treatments. Examples would be Zyper, Thor, Tribenuron-methyl or Tribenuron. Where no autumn treatment was applied, Alister Flex provides considerable power against grass and broadleaved weeds.
With more winter cereals set to go into the ground this autumn, staying on top of troublesome weeds is increasingly important.
Many modern grassweed herbicides utilise actives that are best applied pre-emerge and that means being organised to move during planting, or shortly afterwards. It is also increasingly difficult to achieve full control of grass and broadleaved weeds with a single treatment. This means that sequences must be planned, especially for awkward grassweeds. Herbicide resistance adds a further complication.
All of these changes mean that pre-emerge options should be targeted, where possible. There are reasonable grassweed products available for use post-emergence in wheat, but this is more challenging in barley.
Wheat
There are numerous products that can be used pre- or post-emergence on wheat, but many work better pre-emerge, providing seedbed conditions are suitable. The main actives used for grass and broadleaved weed control are those containing flufenacet and diflufenican (DFF). These products can also be applied post-emerge.
These actives are found in products such as Firebird, Navigate, Griffen, Reliance and Naceto. Different products have different application rates and they vary in the number of treatments allowed. So, check the label before use. Rates also differ for wheat and barley.
Both actives are also available as single ingredients. Diflufenican is available as Diflanil, Hurricane, Stride and FarmCo Dazzle (plus others). Straight flufenacet is available as Fence, Glosset, and Clayton Tacit. Again, check the label, because rates differ.
Another commonly used active is pendimethalin (PDM). This can be bought alone as products such as Stomp Aqua or Most Micro, in combination with DFF in products like Bulldog and Adept, or with picolinafen as Flight.
Another active for use in combinations is prosulfocarb. This is contained in products like Defy, Crozier and Roxy 800C. These are generally applied pre-emerge, but rate and application details differ, eg Defy. Prosulfocarb is also sold in a mix with DFF as Purelo.
Monolith is a post-emergence option for use on wheat, rye, and triticale. It is particularly strong on grassweeds and is used to target sterile brome, blackgrass, wild oats and meadowgrasses. It can be used up to GS33, but earlier application is preferable.
Broadway Star is used as part of a programme to tackle sterile brome in particular. However, it needs to have PDM applied in advance to tackle annual meadowgrass. It should be used in early spring with an adjuvant.
Barley
Control of certain grassweeds, such as sterile brome in winter barley, is particularly difficult due to the lack of chemistry.
Products containing flufenacet, which include Firebird, Navigate, Griffen and Reliance, have good residual control on grass weeds, especially annual meadow grass, and are also good on broadleaved weeds. Rates vary between individual products, however.
Prosulfocarb, ie Defy, is a very good option for high annual meadowgrass situations – but avoid use at pre-emerge on winter barley. Add DFF for additional broadleaved weed control. Pendimethalin-based products – Stomp Aqua, Most Micro (various rates) etc – have good residual activity for pre-emerge situations and are good on annual meadowgrass. Generally better on fumitory than DFF, but weak on groundsel.Tower, which contains chlorotoluron, PDM and DFF, is good on annual meadowgrass plus broadleaved weeds. A 9m buffer zone is required along water courses. Baraca Triple at 0.7l/ha is good on annual meadow grass and a range of broadleaved weeds as an early post-emerge. Avadex Factor, which contains tri-allate, targets grass and other weeds pre-emerge as part of a program.Diflufenican, ie Diflanil 500, Hurricane and Stride, is useful against a range of broadleaved weeds. It is poor on fumitory and poppy, however. Pendimethalin plus picolinafen ie Flight, is good on cleavers, poppy and fumitory, but is weak on groundsel. Use pre-emerge for best annual meadowgrass control. Pendimethalin and DFF mixes, such as Adept or Bulldog, control a broad spectrum of broadleaved weeds. Adjust rates for post-emerge. Fence or Flosset, containing flufenacet, at 0.5l/ha or 0.4l/ha respectively, are good on grass weed control when used early and is generally a tank mix partner for DFF and PDM mixes. Three-way mixes
Three-way mixes include Bacara Triple and Tower. These can be applied pre- or early post-emergence. Bacara Triple is a mix of flufenacet, DFF and metribuzin, while Tower is a mix of PDM, chlorotoluron and DFF. Bacara Triple can be applied up to GS13, but Tower can be applied up to GS30.
Programmed approach
With resistance being an ever-increasing issue, the re-introduction of Avadex Factor for pre-emerge on winter wheat provides another option for control of blackgrass, sterile brome and other serious grass problems.
It can be applied with flufenacet +/- DFF or PDM. It must always be used as part of a programme. A follow up treatment will always be required.
Post-emerge or tidy-up sprays
There are many other herbicides that can be used to tidy up problem weeds that escaped autumn treatments. Examples would be Zyper, Thor, Tribenuron-methyl or Tribenuron. Where no autumn treatment was applied, Alister Flex provides considerable power against grass and broadleaved weeds.
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